WorldWideScience

Sample records for deposited diamond coatings

  1. Diamond coating deposition by synergy of thermal and laser methods-A problem revisited

    International Nuclear Information System (INIS)

    Ristic, Gordana S.; Trtica, Milan S.; Bogdanov, Zarko D.; Romcevic, Nebojsa Z.; Miljanic, Scepan S.

    2007-01-01

    Diamond coatings were deposited by synergy of the hot filament CVD method and the pulse TEA CO 2 laser, in spectroactive and spectroinactive diamond precursor atmospheres. Resulting diamond coatings are interpreted relying on evidence of scanning electron microscopy as well as microRaman spectroscopy. Thermal synergy component (hot filament) possesses an activating agent for diamond deposition, and contributes significantly to quality and extent of diamond deposition. Laser synergy component comprises a solid surface modification as well as the spectroactive gaseous atmosphere modification. Surface modification consists in changes of the diamond coating being deposited and, at the same time, in changes of the substrate surface structure. Laser modification of the spectroactive diamond precursor atmosphere means specific consumption of the precursor, which enables to skip the deposition on a defined substrate location. The resulting process of diamond coating elimination from certain, desired locations using the CO 2 laser might contribute to tailoring diamond coatings for particular applications. Additionally, the substrate laser modification could be optimized by choice of a proper spectroactive precursor concentration, or by a laser radiation multiple pass through an absorbing medium

  2. Microwave plasma deposition of diamond like carbon coatings

    Indian Academy of Sciences (India)

    Abstract. The promising applications of the microwave plasmas have been appearing in the fields of chemical processes and semiconductor manufacturing. Applications include surface deposition of all types including diamond/diamond like carbon (DLC) coatings, etching of semiconductors, promotion of organic reactions, ...

  3. Recent Advances in the Deposition of Diamond Coatings on Co-Cemented Tungsten Carbides

    Directory of Open Access Journals (Sweden)

    R. Polini

    2012-01-01

    Full Text Available Co-cemented tungsten carbides, namely, hard metals are largely used to manufacture high wear resistant components in several manufacturing segments. Coating hard metals with superhard materials like diamond is of utmost interest as it can further extend their useful lifespan. The deposition of diamond coatings onto WC-Co can be extremely complicated as a result of poor adhesion. This can be essentially ascribed to (i the mismatch in thermal expansion coefficients between diamond and WC-Co, at the typical high temperatures inside the chemical vapour deposition (CVD chamber, generates large residual stresses at the interface; (ii the role of surface Co inside the WC-Co matrix during diamond CVD, which promotes carbon dissolution and diffusion. The present investigation reviews the techniques by which Co-cemented tungsten carbides can be treated to make them prone to receive diamond coatings by CVD. Further, it proposes interesting ecofriendly and sustainable alternatives to further improve the diamond deposition process as well as the overall performance of the coated hard metals.

  4. Beneficial effects of laser irradiation on the deposition process of diamond/Ni60 composite coating with cold spray

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Jianhua, E-mail: laser@zjut.edu.cn; Yang, Lijing; Li, Bo; Li, Zhihong

    2015-03-01

    Graphical abstract: - Highlights: • The hard Ni-based alloy powder as matrix in diamond composite coating was studied. • The influence of laser on diamond distribution of composite coating was analyzed. • The graphitization of diamond was prohibited in supersonic laser deposition process. • The abrasion mechanisms of diamond/Ni60 composite coating were discussed. - Abstract: Although cold spray process has many unique advantages over other coating techniques, it has difficulties in depositing hard materials. This article presents a study in the beneficial effects of laser irradiation on the fabrication process of diamond/Ni60 composite coating using cold spray. The focus of this research is on the comparison between the composite coatings produced with laser cladding (LC) and with supersonic laser deposition (SLD), with respect to diamond graphitization and tribological properties, thus to demonstrate the beneficial effects of laser irradiation on the cold spray process. The influence of deposition temperature on the coating characteristics, such as deposition efficiency, diamond volume fraction, microstructure and phase is also investigated. The tribological properties of the diamond/Ni60 composite coating produced with SLD are determined using a pin-on-disc tribometer, along with the diamond/Ni60 coating produced using LC with the optimal process parameters for comparison. The experimental results show that with the assistance of laser irradiation, diamond/Ni60 composite coating can be successfully deposited using cold spray; the obtained coating is superior to that processed with LC, because SLD can suppress the graphitization of the diamond particles. The diamond/Ni60 composite coating fabricated with SLD has much better tribological properties than the LC coating.

  5. Friction and wear properties of diamonds and diamond coatings

    International Nuclear Information System (INIS)

    Hayward, I.P.

    1991-01-01

    The recent development of chemical vapor deposition techniques for diamond growth enables bearings to be designed which exploit diamond's low friction and extreme resistance to wear. However, currently produced diamond coatings differ from natural diamond surfaces in that they are polycrystalline and faceted, and often contain appreciable amounts of non-diamond material (i.e. graphitic or amorphous carbon). Roughness, in particular, influences the friction and wear properties; rough coatings severely abrade softer materials, and can even wear natural diamond sliders. Nevertheless, the best available coatings exhibit friction coefficients as low as those of natural diamond and are highly resistant to wear. This paper reviews the tribological properties of natural diamond, and compares them with those of chemical vapor deposited diamond coatings. Emphasis is placed on the roles played by roughness and material transfer in controlling frictional behavior. (orig.)

  6. CVD diamond deposition onto dental burs

    International Nuclear Information System (INIS)

    Ali, N.; Sein, H.

    2001-01-01

    A hot-filament chemical vapor deposition (HFCVD) system has been modified to enable non-planar substrates, such as metallic wires and dental burs, to be uniformly coated with thin polycrystalline diamond films. Initially, diamond deposition was carried out on titanium and tantalum wires in order to test and optimize the system. High growth rates of the order of approx. 8 /hr were obtained when depositing diamond on titanium wires using the vertical filament arrangement. However, lower growth rates of the order of 4-5meu m/hr were obtained with diamond deposition on tantalum wires. To extend the work towards a practical biomedical application tungsten carbide dental burs were coated with diamond films. The as-grown films were found to be polycrystalline and uniform over the cutting tip. Finally, the costs relating to diamond CVD onto dental burs have been presented in this paper. The costs relating to coating different number of burs at a time and the effect of film thickness on costs have been included in this investigation. (author)

  7. Transparent nanocrystalline diamond coatings and devices

    Science.gov (United States)

    Sumant, Anirudha V.; Khan, Adam

    2017-08-22

    A method for coating a substrate comprises producing a plasma ball using a microwave plasma source in the presence of a mixture of gases. The plasma ball has a diameter. The plasma ball is disposed at a first distance from the substrate and the substrate is maintained at a first temperature. The plasma ball is maintained at the first distance from the substrate, and a diamond coating is deposited on the substrate. The diamond coating has a thickness. Furthermore, the diamond coating has an optical transparency of greater than about 80%. The diamond coating can include nanocrystalline diamond. The microwave plasma source can have a frequency of about 915 MHz.

  8. HFCVD Diamond-Coated Mechanical Seals

    Directory of Open Access Journals (Sweden)

    Raul Simões

    2018-05-01

    Full Text Available A mechanical seal promotes the connection between systems or mechanisms, preventing the escape of fluids to the exterior. Nonetheless, due to extreme working conditions, premature failure can occur. Diamond, due to its excellent properties, is heralded as an excellent choice to cover the surface of these devices and extend their lifetime. Therefore, the main objective of this work was to deposit diamond films over mechanical seals and test the coated seals on a water pump, under real working conditions. The coatings were created by hot filament chemical vapor deposition (HFCVD and two consecutive layers of micro- and nanocrystalline diamond were deposited. One of the main difficulties is the attainment of a good adhesion between the diamond films and the mechanical seal material (WC-Co. Nucleation, deposition conditions, and pre-treatments were studied to enhance the coating. Superficial wear or delamination of the film was investigated using SEM and Raman characterization techniques, in order to draw conclusions about the feasibility of these coatings in the WC-Co mechanical seals with the purpose of increasing their performance and life time. The results obtained gave a good indication about the feasibility of this process and the deposition conditions used, with the mechanical seals showing no wear and no film delamination after a real work environment test.

  9. Diamond deposition on siliconized stainless steel

    International Nuclear Information System (INIS)

    Alvarez, F.; Reinoso, M.; Huck, H.; Rosenbusch, M.

    2010-01-01

    Silicon diffusion layers in AISI 304 and AISI 316 type stainless steels were investigated as an alternative to surface barrier coatings for diamond film growth. Uniform 2 μm thick silicon rich interlayers were obtained by coating the surface of the steels with silicon and performing diffusion treatments at 800 deg. C. Adherent diamond films with low sp 2 carbon content were deposited on the diffused silicon layers by a modified hot filament assisted chemical vapor deposition (HFCVD) method. Characterization of as-siliconized layers and diamond coatings was performed by energy dispersive X-ray analysis, scanning electron microscopy, X-ray diffraction and Raman spectroscopy.

  10. Co-electrodeposition of hard Ni-W/diamond nanocomposite coatings

    Science.gov (United States)

    Zhang, Xinyu; Qin, Jiaqian; Das, Malay Kumar; Hao, Ruru; Zhong, Hua; Thueploy, Adisak; Limpanart, Sarintorn; Boonyongmaneerat, Yuttanant; Ma, Mingzhen; Liu, Riping

    2016-02-01

    Electroplated hard chrome coating is widely used as a wear resistant coating to prolong the life of mechanical components. However, the electroplating process generates hexavalent chromium ion which is known carcinogen. Hence, there is a major effort throughout the electroplating industry to replace hard chrome coating. Composite coating has been identified as suitable materials for replacement of hard chrome coating, while deposition coating prepared using traditional co-deposition techniques have relatively low particles content, but the content of particles incorporated into a coating may fundamentally affect its properties. In the present work, Ni-W/diamond composite coatings were prepared by sediment co-electrodeposition from Ni-W plating bath, containing suspended diamond particles. This study indicates that higher diamond contents could be successfully co-deposited and uniformly distributed in the Ni-W alloy matrix. The maximum hardness of Ni-W/diamond composite coatings is found to be 2249 ± 23 Hv due to the highest diamond content of 64 wt.%. The hardness could be further enhanced up to 2647 ± 25 Hv with heat treatment at 873 K for 1 h in Ar gas, which is comparable to hard chrome coatings. Moreover, the addition of diamond particles could significantly enhance the wear resistance of the coatings.

  11. Pulsed laser deposition of metallic films on the surface of diamond particles for diamond saw blades

    International Nuclear Information System (INIS)

    Jiang Chao; Luo Fei; Long Hua; Hu Shaoliu; Li Bo; Wang Youqing

    2005-01-01

    Ti or Ni films have been deposited on the diamond particle surfaces by pulsed laser deposition. Compressive resistance of the uncoated and coated diamond particles was measured, respectively, in the experiments. The compressive resistance of the Ti-coated diamonds particles was found much higher than that of the uncoated ones. It increased by 39%. The surface morphology is observed by the metallography microscope. The surface of the uncoated diamonds particles had many hollows and flaws, while the surface of Ni-coated diamond particles was flat and smooth, and the surface of Ti-coated diamond particles had some metal masses that stood out of the surface of the Ti-coated film. The components of the metallic films of diamond particles were examined by X-ray diffractometry (XRD). TiC was found formed on the Ti-coated diamond surface, which resulted in increased surface bonding strength between the diamond particles and the Ti films. Meanwhile, TiC also favored improving the bonding strength between the coated diamond particles and the binding materials. Moreover, the bending resistance of the diamond saw blade made of Ti-coated diamond was drastically higher than that of other diamond saw blades, which also played an important role in improving the blade's cutting ability and lifetime. Therefore, it was most appropriate that the diamond saw blade was made of Ti-coated diamond particles rather than other materials

  12. A comparative machining study of diamond-coated tools made by ...

    Indian Academy of Sciences (India)

    The successful implementation of diamond coatings also expedited similar research in the deposition of cubic boron nitride. This paper presents superhard coating tools, with emphasis on diamond-coated WC–Co tools, the corresponding deposition of technologies and the foreseen metal-cutting applications.

  13. Mechanical pretreatment for improved adhesion of diamond coatings

    International Nuclear Information System (INIS)

    Toenshoff, H.K.; Mohlfeld, A.; Gey, C.; Winkler, J.

    1999-01-01

    Diamond coatings are mainly used in cutting processes due to their tribological characteristics. They show a high hardness, low friction coefficient, high wear resistance and good chemical inertness. In relation to polycrystalline diamond (PCD)-tipped cutting inserts, especially the advantageous chemical stability of diamond coatings is superior as no binder phases between diamond grains are used. However, the deposition of adherent high-quality diamond coatings has been found difficult. Thus, substrate pretreatment is utilised to improve film adhesion. This investigation is based on water peening of the substrate material before coating. The investigation revealed best results for diamond film adhesion on pretreated substrates compared to conventional diamond coatings on cemented carbide tools applied with the CVD hot-filament process. In final cutting tests with increased film adhesion trough water peened cutting tools an improved wear behavior was detected. (orig.)

  14. Surface hardening of optic materials by deposition of diamond like carbon coatings from separated plasma of arc discharge

    Science.gov (United States)

    Osipkov, A. S.; Bashkov, V. M.; Belyaeva, A. O.; Stepanov, R.; Mironov, Y. M.; Galinovsky, A. L.

    2015-02-01

    This article considers the issue of strengthening of optic materials used in the IR spectrum by deposition of diamond like carbon coatings from separated plasma arc discharge. The report shows results of tests of bare and strengthened optical materials such as BaF2, MgF2, Si, Ge, including the testing of their strength and spectral characteristics. Results for the determination of optical constants for the DLC coatings deposited on substrates of Ge and Si, by using separated plasma, are also presented. Investigations showed that surface hardening of optical materials operable in the IR range, by the deposition of diamond like carbon coating onto their surface, according to this technology, considerably improves operational properties and preserves or improves their optic properties.

  15. Diamond-like carbon coated ultracold neutron guides

    International Nuclear Information System (INIS)

    Heule, S.; Atchison, F.; Daum, M.; Foelske, A.; Henneck, R.; Kasprzak, M.; Kirch, K.; Knecht, A.; Kuzniak, M.; Lippert, T.; Meier, M.; Pichlmaier, A.; Straumann, U.

    2007-01-01

    It has been shown recently that diamond-like carbon (DLC) with a sp 3 fraction above 60% is a better wall coating material for ultracold neutron applications than beryllium. We report on results of Raman spectroscopic and XPS measurements obtained for diamond-like carbon coated neutron guides produced in a new facility, which is based on pulsed laser deposition at 193 nm. For diamond-like carbon coatings on small stainless steel substrates we find sp 3 fractions in the range from 60 to 70% and showing slightly increasing values with laser pulse energy and pulse repetition rate

  16. Novel diamond-coated tools for dental drilling applications.

    Science.gov (United States)

    Jackson, M J; Sein, H; Ahmed, W; Woodwards, R

    2007-01-01

    The application of diamond coatings on cemented tungsten carbide (WC-Co) tools has been the subject of much attention in recent years in order to improve cutting performance and tool life in orthodontic applications. WC-Co tools containing 6% Co metal and 94% WC substrate with an average grain size of 1 - 3 microm were used in this study. In order to improve the adhesion between diamond and WC substrates it is necessary to etch cobalt from the surface and prepare it for subsequent diamond growth. Alternatively, a titanium nitride (TiN) interlayer can be used prior to diamond deposition. Hot filament chemical vapour deposition (HFCVD) with a modified vertical filament arrangement has been employed for the deposition of diamond films to TiN and etched WC substrates. Diamond film quality and purity has been characterized using scanning electron microscopy (SEM) and micro Raman spectroscopy. The performances of diamond-coated WC-Co tools, uncoated WC-Co tools, and diamond embedded (sintered) tools have been compared by drilling a series of holes into various materials such as human tooth, borosilicate glass, and acrylic tooth materials. Flank wear has been used to assess the wear rates of the tools when machining biomedical materials such as those described above. It is shown that using an interlayer such as TiN prior to diamond deposition provides the best surface preparation for producing dental tools.

  17. Preparation of Ti-coated diamond particles by microwave heating

    International Nuclear Information System (INIS)

    Gu, Quanchao; Peng, Jinghui; Xu, Lei; Srinivasakannan, C.

    2016-01-01

    Highlights: • The Ti-Coated diamond particles have been prepared using by microwave heating. • The uniform and dense coating can be produced, and the TiC species was formed. • With increases the temperature results in the thickness of coating increased. • The coating/diamond interfacial bonding strength increased with temperature increasing until 760 °C, then decreased. - Abstract: Depositing strong carbide-forming elements on diamond surface can dramatically improve the interfacial bonding strength between diamond grits and metal matrix. In the present work, investigation on the preparation of Ti-coated diamond particles by microwave heating has been conducted. The morphology, microstructure, and the chemical composition of Ti-coated diamond particles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive x-ray spectrometer (EDX). The thickness of Ti coating was measured and the interfacial binding strength between Ti coating and diamond was analyzed. The results show that the surface of the diamond particles could be successfully coated with Ti, forming a uniform and continuous Ti-coated layer. The TiC was found to form between the surface of diamond particles and Ti-coated layer. The amount of TiC as well as the thickness of coating increased with increasing coating temperature, furthermore, the grain size of the coating also grew gradually. The interfacial bonding strength between coating and diamond was found to be best at the temperature of 760 °C.

  18. Preparation of Ti-coated diamond particles by microwave heating

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Quanchao [National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Yunnan Copper Smelting and Processing Complex, Yunnan Copper (Group) CO., LTD., Kunming 650102 (China); International Joint Research Center of Advanced Preparation of Superhard Materials Field, Kunming Academician Workstation of Advanced Preparation of Superhard Materials Field, Kunming 650093 (China); Peng, Jinghui [National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); International Joint Research Center of Advanced Preparation of Superhard Materials Field, Kunming Academician Workstation of Advanced Preparation of Superhard Materials Field, Kunming 650093 (China); Xu, Lei, E-mail: xulei_kmust@aliyun.com [National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Mechanical Engineering, University of Washington, Seattle, WA 98195 (United States); International Joint Research Center of Advanced Preparation of Superhard Materials Field, Kunming Academician Workstation of Advanced Preparation of Superhard Materials Field, Kunming 650093 (China); Srinivasakannan, C. [Chemical Engineering Department, The Petroleum Institute, P.O. Box 2533, Abu Dhabi (United Arab Emirates); and others

    2016-12-30

    Highlights: • The Ti-Coated diamond particles have been prepared using by microwave heating. • The uniform and dense coating can be produced, and the TiC species was formed. • With increases the temperature results in the thickness of coating increased. • The coating/diamond interfacial bonding strength increased with temperature increasing until 760 °C, then decreased. - Abstract: Depositing strong carbide-forming elements on diamond surface can dramatically improve the interfacial bonding strength between diamond grits and metal matrix. In the present work, investigation on the preparation of Ti-coated diamond particles by microwave heating has been conducted. The morphology, microstructure, and the chemical composition of Ti-coated diamond particles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive x-ray spectrometer (EDX). The thickness of Ti coating was measured and the interfacial binding strength between Ti coating and diamond was analyzed. The results show that the surface of the diamond particles could be successfully coated with Ti, forming a uniform and continuous Ti-coated layer. The TiC was found to form between the surface of diamond particles and Ti-coated layer. The amount of TiC as well as the thickness of coating increased with increasing coating temperature, furthermore, the grain size of the coating also grew gradually. The interfacial bonding strength between coating and diamond was found to be best at the temperature of 760 °C.

  19. [The change of bacterial adhesion during deposition nitrogen-diamond like carbon coating on pure titanium].

    Science.gov (United States)

    Yin, Lu; Xiao, Yun

    2011-10-01

    The aim of this study was to observe the change of bacterial adhesion on pure titanium coated with nitrogen-diamond like carbon (N-DLC) films and to guide the clinical application. N-DLC was deposited on titanium using ion plating machine, TiN film, anodic oxide film and non-deposition were used as control, then made specimens adhering on the surface of resin denture base for 6 months. The adhesion of Saccharomyces albicans on the titanium surface was observed using scanning electron microscope, and the roughness was tested by roughness detector. The number of Saccharomyces albicans adhering on diamond-like carbon film was significantly less than on the other groups (P DLC film was less than other group (P coated with N-DLC film reduced the adhesion of Saccharomyces albicans after clinical application, thereby reduced the risk of denture stomatitis.

  20. Tribological wear behavior of diamond reinforced composite coating

    International Nuclear Information System (INIS)

    Venkateswarlu, K.; Ray, Ajoy Kumar; Gunjan, Manoj Kumar; Mondal, D.P.; Pathak, L.C.

    2006-01-01

    In the present study, diamond reinforced composite (DRC) coating has been applied on mild steel substrate using thermal spray coating technique. The composite powder consists of diamond, tungsten carbide, and bronze, which was mixed in a ball mill prior deposition by thermal spray. The microstructure and the distribution of diamond and tungsten carbide particle in the bronze matrix were studied. The DRC-coated mild steel substrates were assessed in terms of their high stress abrasive wear and compared with that of uncoated mild steel substrates. It was observed that when sliding against steel, the DRC-coated sample initially gains weight, but then loses the transferred counter surface material. In case of abrasive wear, the wear rate was greatly reduced due to the coating; wherein the wear rate decreased with increase in diamond content

  1. Electrochemically assisted deposition of hydroxyapatite on Ti6Al4V substrates covered by CVD diamond films — Coating characterization and first cell biological results

    Energy Technology Data Exchange (ETDEWEB)

    Strąkowska, Paulina [Gdańsk University of Technology, Mechanical Engineering Faculty (Poland); Gdańsk University of Technology, Faculty of Electronics, Telecommunications, and Informatics (Poland); Beutner, René [Max Bergmann Center, Technische Universität Dresden (Germany); Gnyba, Marcin [Gdańsk University of Technology, Faculty of Electronics, Telecommunications, and Informatics (Poland); Zielinski, Andrzej [Gdańsk University of Technology, Mechanical Engineering Faculty (Poland); Scharnweber, Dieter, E-mail: Dieter.Scharnweber@tu-dresden.de [Max Bergmann Center, Technische Universität Dresden (Germany)

    2016-02-01

    Although titanium and its alloys are widely used as implant material for orthopedic and dental applications they show only limited corrosion stability and osseointegration in different cases. The aim of the presented research was to develop and characterize a novel surface modification system from a thin diamond base layer and a hydroxyapatite (HAp) top coating deposited on the alloy Ti6Al4V widely used for implants in contact with bone. This coating system is expected to improve both the long-term corrosion behavior and the biocompatibility and bioactivity of respective surfaces. The diamond base films were obtained by Microwave Plasma Assisted Chemical Vapor Deposition (MW-PACVD); the HAp coatings were formed in aqueous solutions by electrochemically assisted deposition (ECAD) at varying polarization parameters. Scanning electron microscopy (SEM), Raman microscopy, and electrical conductivity measurements were applied to characterize the generated surface states; the calcium phosphate coatings were additionally chemically analyzed for their composition. The biological properties of the coating system were assessed using hMSC cells analyzing for cell adhesion, proliferation, and osteogenic differentiation. Varying MW-PACVD process conditions resulted in composite coatings containing microcrystalline diamond (MCD/Ti-C), nanocrystalline diamond (NCD), and boron-doped nanocrystalline diamond (B-NCD) with the NCD coatings being dense and homogeneous and the B-NCD coatings showing increased electrical conductivity. The ECAD process resulted in calcium phosphate coatings from stoichiometric and non-stoichiometric HAp. The deposition of HAp on the B-NCD films run at lower cathodic potentials and resulted both in the highest coating mass and the most homogenous appearance. Initial cell biological investigations showed an improved cell adhesion in the order B-NCD > HAp/B-NCD > uncoated substrate. Cell proliferation was improved for both investigated coatings whereas ALP

  2. Electrochemically assisted deposition of hydroxyapatite on Ti6Al4V substrates covered by CVD diamond films — Coating characterization and first cell biological results

    International Nuclear Information System (INIS)

    Strąkowska, Paulina; Beutner, René; Gnyba, Marcin; Zielinski, Andrzej; Scharnweber, Dieter

    2016-01-01

    Although titanium and its alloys are widely used as implant material for orthopedic and dental applications they show only limited corrosion stability and osseointegration in different cases. The aim of the presented research was to develop and characterize a novel surface modification system from a thin diamond base layer and a hydroxyapatite (HAp) top coating deposited on the alloy Ti6Al4V widely used for implants in contact with bone. This coating system is expected to improve both the long-term corrosion behavior and the biocompatibility and bioactivity of respective surfaces. The diamond base films were obtained by Microwave Plasma Assisted Chemical Vapor Deposition (MW-PACVD); the HAp coatings were formed in aqueous solutions by electrochemically assisted deposition (ECAD) at varying polarization parameters. Scanning electron microscopy (SEM), Raman microscopy, and electrical conductivity measurements were applied to characterize the generated surface states; the calcium phosphate coatings were additionally chemically analyzed for their composition. The biological properties of the coating system were assessed using hMSC cells analyzing for cell adhesion, proliferation, and osteogenic differentiation. Varying MW-PACVD process conditions resulted in composite coatings containing microcrystalline diamond (MCD/Ti-C), nanocrystalline diamond (NCD), and boron-doped nanocrystalline diamond (B-NCD) with the NCD coatings being dense and homogeneous and the B-NCD coatings showing increased electrical conductivity. The ECAD process resulted in calcium phosphate coatings from stoichiometric and non-stoichiometric HAp. The deposition of HAp on the B-NCD films run at lower cathodic potentials and resulted both in the highest coating mass and the most homogenous appearance. Initial cell biological investigations showed an improved cell adhesion in the order B-NCD > HAp/B-NCD > uncoated substrate. Cell proliferation was improved for both investigated coatings whereas ALP

  3. Coating of diamond-like carbon nanofilm on alumina by microwave plasma enhanced chemical vapor deposition process.

    Science.gov (United States)

    Rattanasatien, Chotiwan; Tonanon, Nattaporn; Bhanthumnavin, Worawan; Paosawatyanyong, Boonchoat

    2012-01-01

    Diamond-like carbon (DLC) nanofilms with thickness varied from under one hundred to a few hundred nanometers have been successfully deposited on alumina substrates by microwave plasma enhanced chemical vapor deposition (MW-PECVD) process. To obtain dense continuous DLC nanofilm coating over the entire sample surface, alumina substrates were pre-treated to enhance the nucleation density. Raman spectra of DLC films on samples showed distinct diamond peak at around 1332 cm(-1), and the broad band of amorphous carbon phase at around 1550 cm(-1). Full width at half maximum height (FWHM) values indicated good formation of diamond phase in all films. The result of nano-indentation test show that the hardness of alumina samples increase from 7.3 +/- 2.0 GPa in uncoated samples to 15.8 +/- 4.5-52.2 +/- 2.1 GPa in samples coated with DLC depending on the process conditions. It is observed that the hardness values are still in good range although the thickness of the films is less than a hundred nanometer.

  4. Electrochemically assisted deposition of hydroxyapatite on Ti6Al4V substrates covered by CVD diamond films - Coating characterization and first cell biological results.

    Science.gov (United States)

    Strąkowska, Paulina; Beutner, René; Gnyba, Marcin; Zielinski, Andrzej; Scharnweber, Dieter

    2016-02-01

    Although titanium and its alloys are widely used as implant material for orthopedic and dental applications they show only limited corrosion stability and osseointegration in different cases. The aim of the presented research was to develop and characterize a novel surface modification system from a thin diamond base layer and a hydroxyapatite (HAp) top coating deposited on the alloy Ti6Al4V widely used for implants in contact with bone. This coating system is expected to improve both the long-term corrosion behavior and the biocompatibility and bioactivity of respective surfaces. The diamond base films were obtained by Microwave Plasma Assisted Chemical Vapor Deposition (MW-PACVD); the HAp coatings were formed in aqueous solutions by electrochemically assisted deposition (ECAD) at varying polarization parameters. Scanning electron microscopy (SEM), Raman microscopy, and electrical conductivity measurements were applied to characterize the generated surface states; the calcium phosphate coatings were additionally chemically analyzed for their composition. The biological properties of the coating system were assessed using hMSC cells analyzing for cell adhesion, proliferation, and osteogenic differentiation. Varying MW-PACVD process conditions resulted in composite coatings containing microcrystalline diamond (MCD/Ti-C), nanocrystalline diamond (NCD), and boron-doped nanocrystalline diamond (B-NCD) with the NCD coatings being dense and homogeneous and the B-NCD coatings showing increased electrical conductivity. The ECAD process resulted in calcium phosphate coatings from stoichiometric and non-stoichiometric HAp. The deposition of HAp on the B-NCD films run at lower cathodic potentials and resulted both in the highest coating mass and the most homogenous appearance. Initial cell biological investigations showed an improved cell adhesion in the order B-NCD>HAp/B-NCD>uncoated substrate. Cell proliferation was improved for both investigated coatings whereas ALP

  5. [Influence of deposition time on chromatics during nitrogen-doped diamond like carbon coating on pure titanium].

    Science.gov (United States)

    Yin, Lu; Yao, Jiang-wu; Xu, De-wen

    2010-10-01

    The aim of this study was to observed the influence of deposition time on chromatics during nitrogen-doped diamond like carbon coating (N-DLC) on pure titanium by multi impulse are plasma plating machine. Applying multi impulse are plasma plating machine to produce TiN coatings on pure titanium in nitrogen atmosphere, then filming with nitrogen-doped DLC on TiN in methane (10-80 min in every 5 min). The colors of N-DLC were evaluated in the CIE1976 L*a*b* uniform color scale and Mussell notation. The surface morphology of every specimen was analyzed using scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). When changing the time of N-DLC coating deposition, N-DLC surface showed different color. Golden yellow was presented when deposition time was 30 min. SEM showed that crystallization was found in N-DLC coatings, the structure changed from stable to clutter by varying the deposition time. The chromatics of N-DLC coatings on pure titanium could get golden yellow when deposition time was 30 min, then the crystallized structure was stable.

  6. Sputtered tungsten-based ternary and quaternary layers for nanocrystalline diamond deposition.

    Science.gov (United States)

    Walock, Michael J; Rahil, Issam; Zou, Yujiao; Imhoff, Luc; Catledge, Shane A; Nouveau, Corinne; Stanishevsky, Andrei V

    2012-06-01

    Many of today's demanding applications require thin-film coatings with high hardness, toughness, and thermal stability. In many cases, coating thickness in the range 2-20 microm and low surface roughness are required. Diamond films meet many of the stated requirements, but their crystalline nature leads to a high surface roughness. Nanocrystalline diamond offers a smoother surface, but significant surface modification of the substrate is necessary for successful nanocrystalline diamond deposition and adhesion. A hybrid hard and tough material may be required for either the desired applications, or as a basis for nanocrystalline diamond film growth. One possibility is a composite system based on carbides or nitrides. Many binary carbides and nitrides offer one or more mentioned properties. By combining these binary compounds in a ternary or quaternary nanocrystalline system, we can tailor the material for a desired combination of properties. Here, we describe the results on the structural and mechanical properties of the coating systems composed of tungsten-chromium-carbide and/or nitride. These WC-Cr-(N) coatings are deposited using magnetron sputtering. The growth of adherent nanocrystalline diamond films by microwave plasma chemical vapor deposition has been demonstrated on these coatings. The WC-Cr-(N) and WC-Cr-(N)-NCD coatings are characterized with atomic force microscopy and SEM, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, and nanoindentation.

  7. Tailoring nanocrystalline diamond coated on titanium for osteoblast adhesion.

    Science.gov (United States)

    Pareta, Rajesh; Yang, Lei; Kothari, Abhishek; Sirinrath, Sirivisoot; Xiao, Xingcheng; Sheldon, Brian W; Webster, Thomas J

    2010-10-01

    Diamond coatings with superior chemical stability, antiwear, and cytocompatibility properties have been considered for lengthening the lifetime of metallic orthopedic implants for over a decade. In this study, an attempt to tailor the surface properties of diamond films on titanium to promote osteoblast (bone forming cell) adhesion was reported. The surface properties investigated here included the size of diamond surface features, topography, wettability, and surface chemistry, all of which were controlled during microwave plasma enhanced chemical-vapor-deposition (MPCVD) processes using CH4-Ar-H2 gas mixtures. The hardness and elastic modulus of the diamond films were also determined. H2 concentration in the plasma was altered to control the crystallinity, grain size, and topography of the diamond coatings, and specific plasma gases (O2 and NH3) were introduced to change the surface chemistry of the diamond coatings. To understand the impact of the altered surface properties on osteoblast responses, cell adhesion tests were performed on the various diamond-coated titanium. The results revealed that nanocrystalline diamond (grain sizes diamond and, thus, should be further studied for improving orthopedic applications. Copyright 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.

  8. Growth, microstructure, and field-emission properties of synthesized diamond film on adamantane-coated silicon substrate by microwave plasma chemical vapor deposition

    International Nuclear Information System (INIS)

    Tiwari, Rajanish N.; Chang Li

    2010-01-01

    Diamond nucleation on unscratched Si surface is great importance for its growth, and detailed understanding of this process is therefore desired for many applications. The pretreatment of the substrate surface may influence the initial growth period. In this study, diamond films have been synthesized on adamantane-coated crystalline silicon {100} substrate by microwave plasma chemical vapor deposition from a gaseous mixture of methane and hydrogen gases without the application of a bias voltage to the substrates. Prior to adamantane coating, the Si substrates were not pretreated such as abraded/scratched. The substrate temperature was ∼530 deg. C during diamond deposition. The deposited films are characterized by scanning electron microscopy, Raman spectrometry, x-ray diffraction, and x-ray photoelectron spectroscopy. These measurements provide definitive evidence for high-crystalline quality diamond film, which is synthesized on a SiC rather than clean Si substrate. Characterization through atomic force microscope allows establishing fine quality criteria of the film according to the grain size of nanodiamond along with SiC. The diamond films exhibit a low-threshold (55 V/μm) and high current-density (1.6 mA/cm 2 ) field-emission (FE) display. The possible mechanism of formation of diamond films and their FE properties have been demonstrated.

  9. Effect of substrates on tribological properties of diamond-like carbon coating

    Directory of Open Access Journals (Sweden)

    Renhui ZHANG

    2017-06-01

    Full Text Available In order to well investigate the effect of different substrates on the friction and wear of diamond-like carbon (DLC coating, the DLC coatings are deposited on substrates like the high-speed steel (HSS, SiC and 304 stainless steel by using plasma enhanced chemical vapor deposition method. The diamond-like carbon is prepared. The microstructure of the coatings is characterized using SEM, TEM and Raman. The SEM results exhibit that the total thickness of the coatings is about 6.5 μm, and there's apparent interfaces between layers. The TEM results imply that the coatings have an amorphous structure. Raman spectrum exhibits that G and D peaks are observed, which implies that the deposition coatings are diamond-like carbon coating. The results of tribological tests show that the substrates have a significant effect on the friction and wear of the coating. For different substrates, the transfer film is found on the steel counterpart surface, the wear track of the HSS has a lowest width, and the DLC coating that deposited on HSS exhibits the lowest wear and low friction coefficient (about 0.1.The microstructure of different substrates wear track surfaces is analyzed by using Raman spectrum, and the lowest wear of the HSS is attributed to the lower degree of the graphitization. The research provides reference for preparing the DLC coating with excellent tribological properties.

  10. Performance and characterisation of CVD diamond coated, sintered diamond and WC-Co cutting tools for dental and micromachining applications

    International Nuclear Information System (INIS)

    Sein, Htet; Ahmed, Waqar; Jackson, Mark; Woodwards, Robert; Polini, Riccardo

    2004-01-01

    Diamond coatings are attractive for cutting processes due to their high hardness, low friction coefficient, excellent wear resistance and chemical inertness. The application of diamond coatings on cemented tungsten carbide (WC-Co) tools was the subject of much attention in recent years in order to improve cutting performance and tool life. WC-Co tools containing 6% Co and 94% WC substrate with an average grain size 1-3 μm were used in this study. In order to improve the adhesion between diamond and WC substrates, it is necessary to etch away the surface Co and prepare the surface for subsequent diamond growth. Hot filament chemical vapour deposition with a modified vertical filament arrangement has been employed for the deposition of diamond films. Diamond film quality and purity have been characterised using scanning electron microscopy and micro-Raman spectroscopy. The performance of diamond coated WC-Co bur, uncoated WC-Co bur, and diamond embedded (sintered) bur have been compared by drilling a series of holes into various materials such as human teeth, borosilicate glass and porcelain teeth. Flank wear has been used to assess the wear rates of the tools. The materials subjected to cutting processes have been examined to assess the quality of the finish. Diamond coated WC-Co microdrills and uncoated microdrills were also tested on aluminium alloys. Results show that there was a 300% improvement when the drills were coated with diamond compared to the uncoated tools

  11. A novel Mo-W interlayer approach for CVD diamond deposition on steel

    Science.gov (United States)

    Kundrát, Vojtěch; Zhang, Xiaoling; Cooke, Kevin; Sun, Hailin; Sullivan, John; Ye, Haitao

    2015-04-01

    Steel is the most widely used material in engineering for its cost/performance ratio and coatings are routinely applied on its surface to further improve its properties. Diamond coated steel parts are an option for many demanding industrial applications through prolonging the lifetime of steel parts, enhancement of tool performance as well as the reduction of wear rates. Direct deposition of diamond on steel using conventional chemical vapour deposition (CVD) processes is known to give poor results due to the preferential formation of amorphous carbon on iron, nickel and other elements as well as stresses induced from the significant difference in the thermal expansion coefficients of those materials. This article reports a novel approach of deposition of nanocrystalline diamond coatings on high-speed steel (M42) substrates using a multi-structured molybdenum (Mo) - tungsten (W) interlayer to form steel/Mo/Mo-W/W/diamond sandwich structures which overcome the adhesion problem related to direct magnetron sputtering deposition of pure tungsten. Surface, interface and tribology properties were evaluated to understand the role of such an interlayer structure. The multi-structured Mo-W interlayer has been proven to improve the adhesion between diamond films and steel substrates by acting as an effective diffusion barrier during the CVD diamond deposition.

  12. A novel Mo-W interlayer approach for CVD diamond deposition on steel

    Energy Technology Data Exchange (ETDEWEB)

    Kundrát, Vojtěch; Sullivan, John; Ye, Haitao, E-mail: h.ye@aston.ac.uk [School of Engineering and Applied Science, Aston University, Birmingham, B4 7ET (United Kingdom); Zhang, Xiaoling; Cooke, Kevin; Sun, Hailin [Miba Coating Group: Teer Coatings Ltd, West-Stone-House, West-Stone, Berry-Hill-Industrial-Estate, WR9 9AS, Droitwich (United Kingdom)

    2015-04-15

    Steel is the most widely used material in engineering for its cost/performance ratio and coatings are routinely applied on its surface to further improve its properties. Diamond coated steel parts are an option for many demanding industrial applications through prolonging the lifetime of steel parts, enhancement of tool performance as well as the reduction of wear rates. Direct deposition of diamond on steel using conventional chemical vapour deposition (CVD) processes is known to give poor results due to the preferential formation of amorphous carbon on iron, nickel and other elements as well as stresses induced from the significant difference in the thermal expansion coefficients of those materials. This article reports a novel approach of deposition of nanocrystalline diamond coatings on high-speed steel (M42) substrates using a multi-structured molybdenum (Mo) – tungsten (W) interlayer to form steel/Mo/Mo-W/W/diamond sandwich structures which overcome the adhesion problem related to direct magnetron sputtering deposition of pure tungsten. Surface, interface and tribology properties were evaluated to understand the role of such an interlayer structure. The multi-structured Mo-W interlayer has been proven to improve the adhesion between diamond films and steel substrates by acting as an effective diffusion barrier during the CVD diamond deposition.

  13. A novel Mo-W interlayer approach for CVD diamond deposition on steel

    Directory of Open Access Journals (Sweden)

    Vojtěch Kundrát

    2015-04-01

    Full Text Available Steel is the most widely used material in engineering for its cost/performance ratio and coatings are routinely applied on its surface to further improve its properties. Diamond coated steel parts are an option for many demanding industrial applications through prolonging the lifetime of steel parts, enhancement of tool performance as well as the reduction of wear rates. Direct deposition of diamond on steel using conventional chemical vapour deposition (CVD processes is known to give poor results due to the preferential formation of amorphous carbon on iron, nickel and other elements as well as stresses induced from the significant difference in the thermal expansion coefficients of those materials. This article reports a novel approach of deposition of nanocrystalline diamond coatings on high-speed steel (M42 substrates using a multi-structured molybdenum (Mo – tungsten (W interlayer to form steel/Mo/Mo-W/W/diamond sandwich structures which overcome the adhesion problem related to direct magnetron sputtering deposition of pure tungsten. Surface, interface and tribology properties were evaluated to understand the role of such an interlayer structure. The multi-structured Mo-W interlayer has been proven to improve the adhesion between diamond films and steel substrates by acting as an effective diffusion barrier during the CVD diamond deposition.

  14. Selective formation of diamond-like carbon coating by surface catalyst patterning

    DEFF Research Database (Denmark)

    Palnichenko, A.V.; Mátéfi-Tempfli, M.; Mátéfi-Tempfli, Stefan

    2004-01-01

    The selective formation of diamond-like carbon coating by surface catalyst patterning was studied. DLC films was deposited using plasma enhanced chemical vapor deposition, filtered vacuum arc deposition, laser ablation, magnetron sputtering and ion-beam lithography methods. The DLC coatings were...

  15. The study on diamond-coated insert by DC plasma jet CVD

    International Nuclear Information System (INIS)

    Zhou Kesong; Dai Mingjiang; Song Jinbing; Kuang Tongchun; Liu Zhengyi

    2001-01-01

    Diamond coating were deposited on cemented carbide inserts by DC plasma jet CVD. The cemented carbide inserts were pretreated by methods including chemical etching of Co, Ar/H 2 plasma etching. The characteristics of diamond film, interface structure, adhesion strength and film stress were analysized by different methods such as SEM, XRD, Raman spectrum etc. A comparing experiment of cutting Al - 22 % Si alloy was carried out with diamond-coated cemented carbide inserts and uncoated cemented carbide inserts. The results show that the diamond-coated cemented carbide insert has a great advantage for cutting abrasive high content Al - Si alloy. (author)

  16. Effect of pretreatment and deposition parameters on diamond nucleation in CVD

    International Nuclear Information System (INIS)

    Nazim, E.; Izman, S.; Ourdjini, A.; Shaharoun, A.M.

    2007-01-01

    Chemical vapour deposition (CVD) of diamond films on cemented carbide (WC) has aroused great interest in recent years. The combination of toughness from the WC and the high hardness of diamond results in outstanding wear resistance. This will increase the lifetime and better technical performance of the components made of diamond coated carbide. One of the important steps in the growth of diamond film is the nucleation of diamond as its density strongly influences the diamond growth process, film quality and morphology. In this paper the various effects of surface pretreatment and diamond deposition conditions on the diamond nucleation density are reviewed. (author)

  17. Nickel/Diamond Composite Coating Prepared by High Speed Electrodeposition

    Directory of Open Access Journals (Sweden)

    ZHANG Yan

    2016-10-01

    Full Text Available Nickel/diamond composite coatings were prepared on the basis of a new high speed electroplating bath. The influence of additives, plating parameters and diamond concentration on internal stress was investigated in order to find the solution to decrease the stress introduced by high current density; the micro morphology of the coatings were observed by SEM. The bath and depositing parameters were optimized that thick nickel/diamond composite coatings with low internal stress can be high speed electroplated with a high cathode current density of 30A/dm2. The results show that when plated with bath composition and parameters as follows: sodium dodecyl sulfate 0.5g/L, ammonium acetate 3g/L, sodium citrate 1.5g/L, diamond particles 30g/L; pH value 3-4, temperature 50℃, the composite coatings prepared in high speed have the lowest internal stress.

  18. Nanocrystalline diamond coatings for mechanical seals applications.

    Science.gov (United States)

    Santos, J A; Neto, V F; Ruch, D; Grácio, J

    2012-08-01

    A mechanical seal is a type of seal used in rotating equipment, such as pumps and compressors. It consists of a mechanism that assists the connection of the rotating shaft to the housings of the equipments, preventing leakage or avoiding contamination. A common cause of failure of these devices is end face wear out, thus the use of a hard, smooth and wear resistant coating such as nanocrystalline diamond would be of great importance to improve their working performance and increase their lifetime. In this paper, different diamond coatings were deposited by the HFCVD process, using different deposition conditions. Additionally, the as-grown films were characterized for, quality, morphology and microstructure using scanning electron microscopy (SEM) and Raman spectroscopy. The topography and the roughness of the films were characterized by atomic force microscopy (AFM).

  19. Fabrication of Antireflection Nanodiamond Particle Film by the Spin Coating Deposition Technique

    Directory of Open Access Journals (Sweden)

    Chii-Ruey Lin

    2014-01-01

    Full Text Available Diamond-based antireflective (AR coatings were fabricated using a spin coating of diamond suspension at room temperature as nucleation enhancement procedure and microwave plasma enhanced chemical vapour deposition. Various working pressures were used to investigate their effect on the optical characterization of the as-deposited diamond films. Scanning electron microscopy (SEM and atomic forced microscopy (AFM were employed to analyze the surface properties of the diamond films. Raman spectra and transmission electron microscopy (TEM also were used for analysis of the microstructure of the films. The results showed that working pressure had a significant effect on thickness, surface roughness, and wettability of the as-deposited diamond films. Deposited under 35 Torr or working pressure, the film possessed a low surface roughness of 13.8 nm and fine diamond grain sizes of 35 nm. Reflectance measurements of the films also were carried out using UV-Vis spectrometer and revealed a low reflectance value of the diamond films. The achievement demonstrated feasibility of the proposed spin-coating procedure for large scale production and thus opens up a prospect application of diamond film as an AR coating in industrial optoelectronic device.

  20. The adhesion and tribology analysis of polycrystalline diamond coated on Si3N4 substrate

    International Nuclear Information System (INIS)

    Hamzah, E.; Purniawan, A.

    2007-01-01

    Cauliflower and octahedral structure of polycrystalline diamond was deposited on silicon nitride (Si 3 N 4 ) substrate by microwave plasma assisted chemical vapor deposition (MPACVD). In our earlier work, the effects of deposition parameters namely, % Methane (CH 4 ) diluted in hydrogen (H 2 ), microwave power and chamber pressure on surface morphology were studied. In the present work the polycrystalline diamond coating adhesion and tribology behaviour were investigated. Rockwell C hardness tester and pin-on-disk tribometer were used to determine the adhesion and tribology properties on diamond coating, respectively. The morphology of the diamond before and after indentation was observed using field emission scanning electron microscopy (FESEM). Based on the adhesion analysis results, it was found that octahedral morphology has better adhesion than cauliflower structure. It was indicated by few cracks and less peel-off than cauliflower structure of polycrystalline diamond after indentation. Based on tribology analysis, polycrystalline diamond coated on substrate has better tribology properties than uncoated substrate. (author)

  1. Diamond-like carbon films deposited on polycarbonates by plasma-enhanced chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Guo, C.T. [Department of Computer and Communication, Diwan College of Management, 72141 Taiwan (China)], E-mail: ctguo@dwu.edu.tw

    2008-04-30

    Diamond-like carbon films were coated on optical polycarbonate using plasma-enhanced chemical vapor deposition. A mixture of SiH{sub 4} and CH{sub 4}/H{sub 2} gases was utilized to reduce the internal compressive stress of the deposited films. The structure of the DLC films was characterized as a function of film thickness using Raman spectroscopy. The dependence of G peak positions and the intensity ratio of I{sub D}/I{sub G} on the DLC film thicknesses was analyzed in detail. Other studies involving atomic force microscopy, ultraviolet visible spectrometry, and three adhesion tests were conducted. Good transparency in the visible region, and good adhesion between diamond-like carbon films and polycarbonate were demonstrated. One-time recordings before and after a DLC film was coated on compact rewritable disc substrates were analyzed as a case study. The results reveal that the diamond-like carbon film overcoating the optical polycarbonates effectively protects the storage media.

  2. Nanostructured diamond coatings for orthopaedic applications

    Science.gov (United States)

    CATLEDGE, S.A.; THOMAS, V.; VOHRA, Y.K.

    2013-01-01

    With increasing numbers of orthopaedic devices being implanted, greater emphasis is being placed on ceramic coating technology to reduce friction and wear in mating total joint replacement components, in order to improve implant function and increase device lifespan. In this chapter, we consider ultra-hard carbon coatings, with emphasis on nanostructured diamond, as alternative bearing surfaces for metallic components. Such coatings have great potential for use in biomedical implants as a result of their extreme hardness, wear resistance, low friction and biocompatibility. These ultra-hard carbon coatings can be deposited by several techniques resulting in a wide variety of structures and properties. PMID:25285213

  3. Nanostructured diamond film deposition on curved surfaces of metallic temporomandibular joint implant

    Energy Technology Data Exchange (ETDEWEB)

    Fries, Marc D; Vohra, Yogesh K [Department of Physics, University of Alabama at Birmingham (UAB), Birmingham, AL (United States)

    2002-10-21

    Microwave plasma chemical vapour deposition of nanostructured diamond films was carried out on curved surfaces of Ti-6Al-4V alloy machined to simulate the shape of a temporomandibular joint (TMJ) dental implant. Raman spectroscopy shows that the deposited films are uniform in chemical composition along the radius of curvature of the TMJ condyle. Thin film x-ray diffraction reveals an interfacial carbide layer and nanocrystalline diamond grains in this coating. Nanoindentation hardness measurements show an ultra-hard coating with a hardness value of 60{+-}5 GPa averaged over three samples. (rapid communication)

  4. Fabrication and characterization of boron-doped nanocrystalline diamond-coated MEMS probes

    Science.gov (United States)

    Bogdanowicz, Robert; Sobaszek, Michał; Ficek, Mateusz; Kopiec, Daniel; Moczała, Magdalena; Orłowska, Karolina; Sawczak, Mirosław; Gotszalk, Teodor

    2016-04-01

    Fabrication processes of thin boron-doped nanocrystalline diamond (B-NCD) films on silicon-based micro- and nano-electromechanical structures have been investigated. B-NCD films were deposited using microwave plasma assisted chemical vapour deposition method. The variation in B-NCD morphology, structure and optical parameters was particularly investigated. The use of truncated cone-shaped substrate holder enabled to grow thin fully encapsulated nanocrystalline diamond film with a thickness of approx. 60 nm and RMS roughness of 17 nm. Raman spectra present the typical boron-doped nanocrystalline diamond line recorded at 1148 cm-1. Moreover, the change in mechanical parameters of silicon cantilevers over-coated with boron-doped diamond films was investigated with laser vibrometer. The increase of resonance to frequency of over-coated cantilever is attributed to the change in spring constant caused by B-NCD coating. Topography and electrical parameters of boron-doped diamond films were investigated by tapping mode AFM and electrical mode of AFM-Kelvin probe force microscopy (KPFM). The crystallite-grain size was recorded at 153 and 238 nm for boron-doped film and undoped, respectively. Based on the contact potential difference data from the KPFM measurements, the work function of diamond layers was estimated. For the undoped diamond films, average CPD of 650 mV and for boron-doped layer 155 mV were achieved. Based on CPD values, the values of work functions were calculated as 4.65 and 5.15 eV for doped and undoped diamond film, respectively. Boron doping increases the carrier density and the conductivity of the material and, consequently, the Fermi level.

  5. A multilayer innovative solution to improve the adhesion of nanocrystalline diamond coatings

    Energy Technology Data Exchange (ETDEWEB)

    Poulon-Quintin, A., E-mail: poulon@icmcb-bordeaux.cnrs.fr [CNRS, ICMCB, UPR 9048, F-33600 Pessac (France); Univ. Bordeaux, ICMCB, UPR 9048, F-33600 Pessac (France); Faure, C.; Teulé-Gay, L.; Manaud, J.P. [CNRS, ICMCB, UPR 9048, F-33600 Pessac (France); Univ. Bordeaux, ICMCB, UPR 9048, F-33600 Pessac (France)

    2015-03-15

    Highlights: • Improvement of the NCD adhesion on WC-12%Co substrates for tooling applications using a multi-interlayer additional system. • Reduction of the graphite layer thickness and continuity at the interface with the diamond. • Transmission electron microscopy study for a better understanding of the diffusion phenomena occurring at the interfaces. - Abstract: Nano-crystalline diamond (NCD) films grown under negative biased substrates by chemical vapor deposition (CVD) are widely used as surface overlay coating onto cermet WC-Co cutting tools to get better performances. To improve the diamond adhesion to the cermet substrate, suitable multi-layer systems have been added. They are composed of a cobalt diffusion barrier close to the substrate (single and sequenced nitrides layers) coated with a nucleation extra layer to improve the nucleus density of diamond during CVD processing. For all systems, before and after diamond deposition, transmission electron microscopy (TEM) has been performed for a better understanding of the diffusion phenomena occurring at the interfaces and to evaluate the presence of graphitic species at the interface with the diamond. Innovative multilayer system dedicated to the regulation of cobalt diffusion coated with a bilayer system optimized for the carbon diffusion control, is shown as an efficient solution to significantly reduce the graphite layer formation at the interface with the diamond down to 10 nm thick and to increase the adhesion of NCD diamond layer as scratch-tests confirm.

  6. Characterization of diamond-like carbon coatings prepared by pulsed bias cathodic vacuum arc deposition

    International Nuclear Information System (INIS)

    Wu Jinbao; Chang, J.-J.; Li, M.-Y.; Leu, M.-S.; Li, A.-K.

    2007-01-01

    Hydrogen free diamond-like carbon (DLC) coatings have been deposited on Si(100) and stainless steel substrates by cathodic vacuum arc plasma deposition with pulse voltage. Adherent deposits on silicon can be obtained through applying gradient Ti/TiC/DLC layers. A pulse bias of - 100 V was applied to the substrate in order to obtain a denser structure of DLC coating approximately 1 μm thick. The microstructure and hardness value of DLC films were analyzed by using X-ray photoelectron spectroscopy and nano-indenter. The experimental results show that the duty cycle strongly influenced the hardness and sp 3 content of the DLC coatings. We observed that when the duty cycle was raised from 2.5% to 12.5%, the hardness increased from 26 GPa to 49 GPa, and the sp 3 fraction of the DLC films measured by XPS increased from 39% to 50.8 % as well. But at constant duty cycle, say 12.5%, the hardness is dropped from 49 to 14 GPa in proportion to the increase of residual gas pressure from 3 x 10 -3 Pa to 1 Pa. As the residual gas pressure increased, collisional phenomenon will decrease the energy of the ions. Ions with low energy make more graphitic carbon links and result in a low hardness value

  7. Diamond-coated ATR prism for infrared absorption spectroscopy of surface-modified diamond nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Remes, Z., E-mail: remes@fzu.cz [Institute of Physics of the ASCR, v.v.i., Cukrovarnicka 10, Praha 6 (Czech Republic); Kozak, H.; Rezek, B.; Ukraintsev, E.; Babchenko, O.; Kromka, A. [Institute of Physics of the ASCR, v.v.i., Cukrovarnicka 10, Praha 6 (Czech Republic); Girard, H.A.; Arnault, J.-C.; Bergonzo, P. [CEA, LIST, Diamond Sensors Laboratory, F-91191 Gif-sur-Yvette (France)

    2013-04-01

    Linear antenna microwave chemical vapor deposition process was used to homogeneously coat a 7 cm long silicon prism by 85 nm thin nanocrystalline diamond (NCD) layer. To show the advantages of the NCD-coated prism for attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) of nanoparticles, we apply diamond nanoparticles (DNPs) of 5 nm nominal size with various surface modifications by a drop-casting of their methanol dispersions. ATR-FTIR spectra of as-received, air-annealed, plasma-oxidized, and plasma-hydrogenated DNPs were measured in the 4000–1500 cm{sup −1} spectral range. The spectra show high spectral resolution, high sensitivity to specific DNP surface moieties, and repeatability. The NCD coating provides mechanical protection against scratching and chemical stability of the surface. Moreover, unlike on bare Si surface, NCD hydrophilic properties enable optically homogeneous coverage by DNPs with some aggregation on submicron scale as evidenced by scanning electron microscopy and atomic force microscopy. Compared to transmission FTIR regime with KBr pellets, direct and uniform deposition of DNPs on NCD-ATR prism significantly simplifies and speeds up the analysis (from days to minutes). We discuss prospects for in situ monitoring of surface modifications and molecular grafting.

  8. Diamond-coated ATR prism for infrared absorption spectroscopy of surface-modified diamond nanoparticles

    Science.gov (United States)

    Remes, Z.; Kozak, H.; Rezek, B.; Ukraintsev, E.; Babchenko, O.; Kromka, A.; Girard, H. A.; Arnault, J.-C.; Bergonzo, P.

    2013-04-01

    Linear antenna microwave chemical vapor deposition process was used to homogeneously coat a 7 cm long silicon prism by 85 nm thin nanocrystalline diamond (NCD) layer. To show the advantages of the NCD-coated prism for attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) of nanoparticles, we apply diamond nanoparticles (DNPs) of 5 nm nominal size with various surface modifications by a drop-casting of their methanol dispersions. ATR-FTIR spectra of as-received, air-annealed, plasma-oxidized, and plasma-hydrogenated DNPs were measured in the 4000-1500 cm-1 spectral range. The spectra show high spectral resolution, high sensitivity to specific DNP surface moieties, and repeatability. The NCD coating provides mechanical protection against scratching and chemical stability of the surface. Moreover, unlike on bare Si surface, NCD hydrophilic properties enable optically homogeneous coverage by DNPs with some aggregation on submicron scale as evidenced by scanning electron microscopy and atomic force microscopy. Compared to transmission FTIR regime with KBr pellets, direct and uniform deposition of DNPs on NCD-ATR prism significantly simplifies and speeds up the analysis (from days to minutes). We discuss prospects for in situ monitoring of surface modifications and molecular grafting.

  9. Regeneration of FBGs during the HFCVD diamond-fiber coating process

    Science.gov (United States)

    Alberto, Nélia J.; Kalinowski, Hypolito J.; Neto, Victor F.; Nogueira, Rogério N.

    2014-08-01

    In this work, the regeneration of saturated fiber Bragg gratings during the diamond coating of the fiber is presented. Due to the high temperatures characteristic of the hot filament chemical vapor deposition (HFCVD) process (around 800 ºC), uniform fiber Bragg gratings (FBGs) are not appropriate to be coated. Nevertheless, regenerated Bragg gratings are a suitable solution for this drawback. Its production process involves the inscription of a saturated FBG followed by a time consuming heat treatment. Here it is proposed to take advantage of the high temperatures characteristic of the HFCVD process to simultaneous regenerate the grating and coat the fiber with diamond.

  10. Nanocrystalline diamond coatings for machining

    Energy Technology Data Exchange (ETDEWEB)

    Frank, M.; Breidt, D.; Cremer, R. [CemeCon AG, Wuerselen (Germany)

    2007-07-01

    This history of CVD diamond synthesis goes back to the fifties of the last century. However, the scientific and economical potential was only gradually recognized. In the eighties, intensive worldwide research on CVD diamond synthesis and applications was launched. Industrial products, especially diamond-coated cutting tools, were introduced to the market in the middle of the nineties. This article shows the latest developments in this area, which comprises nanocrystalline diamond coating structures. (orig.)

  11. Comparative investigation of smooth polycrystalline diamond films on dental burs by chemical vapor deposition

    Science.gov (United States)

    Sein, Htet; Ahmed, Waqar; Rego, Christopher; Jackson, Mark; Polini, Riccardo

    2006-04-01

    Depositions of hot filament chemical vapor-deposited diamond on cobalt-cemented tungsten carbide (WC-Co) rotary cutting dental burs are presented. Conventional dental tools made of sintered polycrystalline diamond have a number of problems associated with the heterogeneity of the crystallite, decreased cutting efficiency, and short life. A preferential (111) faceted diamond was obtained after 15 h of deposition at a growth rate of 1.1 µm/h. Diamond-coated WC-Co dental burs and conventional sintered burs are mainly used in turning, milling, and drilling operations for machining metal ceramic hard alloys such as CoCr, composite teeth, and aluminum alloy in the dental laboratory. The influence of structure, the mechanical characteristics of both diamond grains and hard alloys on the wear behavior, as well as the regimen of grinding on diamond wear are considered. Erosion wear properties are also investigated under air-sand erosion testing. After machining with excessive cutting performance, calculations can be made on flank and crater wear areas. Diamond-coated WC-Co dental burs offered significantly better erosion and wear resistance compared with uncoated WC-Co tools and sintered burs.

  12. Electrochemical Behavior of Biomedical Titanium Alloys Coated with Diamond Carbon in Hanks' Solution

    Science.gov (United States)

    Gnanavel, S.; Ponnusamy, S.; Mohan, L.; Radhika, R.; Muthamizhchelvan, C.; Ramasubramanian, K.

    2018-03-01

    Biomedical implants in the knee and hip are frequent failures because of corrosion and stress on the joints. To solve this important problem, metal implants can be coated with diamond carbon, and this coating plays a critical role in providing an increased resistance to implants toward corrosion. In this study, we have employed diamond carbon coating over Ti-6Al-4V and Ti-13Nb-13Zr alloys using hot filament chemical vapor deposition method which is well-established coating process that significantly improves the resistance toward corrosion, wears and hardness. The diamond carbon-coated Ti-13Nb-13Zr alloy showed an increased microhardness in the range of 850 HV. Electrochemical impedance spectroscopy and polarization studies in SBF solution (simulated body fluid solution) were carried out to understand the in vitro behavior of uncoated as well as coated titanium alloys. The experimental results showed that the corrosion resistance of Ti-13Nb-13Zr alloy is relatively higher when compared with diamond carbon-coated Ti-6Al-4V alloys due to the presence of β phase in the Ti-13Nb-13Zr alloy. Electrochemical impedance results showed that the diamond carbon-coated alloys behave as an ideal capacitor in the body fluid solution. Moreover, the stability in mechanical properties during the corrosion process was maintained for diamond carbon-coated titanium alloys.

  13. Study on effect of plasma surface treatments for diamond deposition by DC arc plasmatron.

    Science.gov (United States)

    Kang, In-Je; Joa, Sang-Beom; Lee, Heon-Ju

    2013-11-01

    To improve the thermal conductivity and wear resistance of ceramic materials in the field of renewable energy technologies, diamond coating by plasma processing has been carried out in recent years. This study's goal is to improve diamond deposition on Al2O3 ceramic substrates by plasma surface treatments. Before diamond deposition was carried out in a vacuum, plasma surface treatments using Ar gas were conducted to improve conditions for deposition. We also conducted plasma processing for diamond deposition on Al2O3 ceramic substrates using a DC arc Plasmatron. The Al2O3 ceramic substrates with diamond film (5 x 15 mm2), were investigated by SEM (Scanning Electron Microscopy), AFM (Atomic Force Microscopy) and XRD (X-ray Diffractometer). Then, the C-H stretching of synthetic diamond films by FTIR (Fourier Transform Infrared Spectroscopy) was studied. We identified nanocrystalline diamond films on the Al2O3 ceramic substrates. The results showed us that the deposition rate of diamond films was 2.3 microm/h after plasma surface treatments. Comparing the above result with untreated ceramic substrates, the deposition rate improved with the surface roughness of the deposited diamond films.

  14. Deposition and micro electrical discharge machining of CVD-diamond layers incorporated with silicon

    Science.gov (United States)

    Kühn, R.; Berger, T.; Prieske, M.; Börner, R.; Hackert-Oschätzchen, M.; Zeidler, H.; Schubert, A.

    2017-10-01

    In metal forming, lubricants have to be used to prevent corrosion or to reduce friction and tool wear. From an economical and ecological point of view, the aim is to avoid the usage of lubricants. For dry deep drawing of aluminum sheets it is intended to apply locally micro-structured wear-resistant carbon based coatings onto steel tools. One type of these coatings are diamond layers prepared by chemical vapor deposition (CVD). Due to the high strength of diamond, milling processes are unsuitable for micro-structuring of these layers. In contrast to this, micro electrical discharge machining (micro EDM) is a suitable process for micro-structuring CVD-diamond layers. Due to its non-contact nature and its process principle of ablating material by melting and evaporating, it is independent of the hardness, brittleness or toughness of the workpiece material. In this study the deposition and micro electrical discharge machining of silicon incorporated CVD-diamond (Si-CVD-diamond) layers were presented. For this, 10 µm thick layers were deposited on molybdenum plates by a laser-induced plasma CVD process (LaPlas-CVD). For the characterization of the coatings RAMAN- and EDX-analyses were conducted. Experiments in EDM were carried out with a tungsten carbide tool electrode with a diameter of 90 µm to investigate the micro-structuring of Si-CVD-diamond. The impact of voltage, discharge energy and tool polarity on process speed and resulting erosion geometry were analyzed. The results show that micro EDM is a suitable technology for micro-structuring of silicon incorporated CVD-diamond layers.

  15. The system of quantum structures coated with the diamond-like carbon for silicon solar cells

    International Nuclear Information System (INIS)

    Efimov, V.P.; Abyzov, A.S.; Luchaninov, A.A.; Omarov, A.O.; Strel'nitskij, V.E.

    2010-01-01

    The peculiarity of the process of amorphous diamond-like carbon coating deposition on the surface of Si photoelectric cell with quantum filaments, which was irradiated by the electrons and heavy multi-charge ions, have been investigated. The experimental results on the investigations of the optical characteristics of the nitrogen doped hydrogenated diamond-like carbon a-C:(H,N) coatings were presented. The parameters of the process of a-C:(H,N) coating deposition on the surfaces of disordered Si semiconductors structures were optimized for the purpose of minimizing optical reflection coefficient from the front surface of the crystal and supplying its mechanical durability.

  16. Wear resistance of nano- and micro-crystalline diamond coatings onto WC-Co with Cr/CrN interlayers

    Energy Technology Data Exchange (ETDEWEB)

    Polini, Riccardo [Dipartimento di Scienze e Tecnologie Chimiche, Universita di Roma Tor Vergata, Via della Ricerca Scientifica, 1, Rome, 00133 (Italy); Barletta, Massimiliano, E-mail: barletta@ing.uniroma2.i [Dipartimento di Ingegneria Meccanica, Universita di Roma Tor Vergata, Via del Politecnico, 1, Rome, 00133 (Italy); Cristofanilli, Giacomo [Dipartimento di Scienze e Tecnologie Chimiche, Universita di Roma Tor Vergata, Via della Ricerca Scientifica, 1, Rome, 00133 (Italy)

    2010-12-30

    Cr/CrN bi-layers have been used recently to promote the growth of high quality Hot Filament Chemical Vapour Deposition (HFCVD) diamond coatings onto Co-cemented tungsten carbide (WC-6 wt.%Co) substrates. In the present investigation, the influence of the crystalline size of the diamond coatings on their wear endurance is looked into. Nano- (NDC) and micro-crystalline Diamond Coatings (MDC) were deposited by HFCVD onto untreated and Fluidized Bed (FB) treated Cr/CrN interlayers. NDCs, characterized by a cauliflower-like morphology, showed improved wear resistance. However, the superimposition of NDCs onto Cr/CrN interlayers micro-corrugated by FB treatment was found to be the most promising choice, leading to the formation of highly adherent and wear resistant coatings.

  17. Polycrystalline Diamond Coating of Additively Manufactured Titanium for Biomedical Applications.

    Science.gov (United States)

    Rifai, Aaqil; Tran, Nhiem; Lau, Desmond W; Elbourne, Aaron; Zhan, Hualin; Stacey, Alastair D; Mayes, Edwin L H; Sarker, Avik; Ivanova, Elena P; Crawford, Russell J; Tran, Phong A; Gibson, Brant C; Greentree, Andrew D; Pirogova, Elena; Fox, Kate

    2018-03-14

    Additive manufacturing using selective laser melted titanium (SLM-Ti) is used to create bespoke items across many diverse fields such as medicine, defense, and aerospace. Despite great progress in orthopedic implant applications, such as for "just in time" implants, significant challenges remain with regards to material osseointegration and the susceptibility to bacterial colonization on the implant. Here, we show that polycrystalline diamond coatings on these titanium samples can enhance biological scaffold interaction improving medical implant applicability. The highly conformable coating exhibited excellent bonding to the substrate. Relative to uncoated SLM-Ti, the diamond coated samples showed enhanced mammalian cell growth, enriched apatite deposition, and reduced microbial S. aureus activity. These results open new opportunities for novel coatings on SLM-Ti devices in general and especially show promise for improved biomedical implants.

  18. CVD Diamond, DLC, and c-BN Coatings for Solid Film Lubrication

    Science.gov (United States)

    Miyoshi, Kazuhisa

    1998-01-01

    When the main criteria for judging coating performance were coefficient of friction and wear rate, which had to be less than 0.1 and 10(exp -6) mm(exp 3)/N-m, respectively, carbon- and nitrogen-ion-implanted, fine-grain CVD diamond and DLC ion beam deposited on fine-grain CVD diamond met the requirements regardless of environment (vacuum, nitrogen, and air).

  19. A comparative machining study of diamond-coated tools made by ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    adherent diamond films on WC–CO tools by all three deposition models and has allowed completion of the ..... cesses with hard turning machining will affect future demand for PCBN (and cBN coated) tools. 6. ... Business Communication Co.

  20. Tensile test of a silicon microstructure fully coated with submicrometer-thick diamond like carbon film using plasma enhanced chemical vapor deposition method

    Science.gov (United States)

    Zhang, Wenlei; Uesugi, Akio; Hirai, Yoshikazu; Tsuchiya, Toshiyuki; Tabata, Osamu

    2017-06-01

    This paper reports the tensile properties of single-crystal silicon (SCS) microstructures fully coated with sub-micrometer thick diamond like carbon (DLC) film using plasma enhanced chemical vapor deposition (PECVD). To minimize the deformations or damages caused by non-uniform coating of DLC, which has high compression residual stress, released SCS specimens with the dimensions of 120 µm long, 4 µm wide, and 5 µm thick were coated from the top and bottom side simultaneously. The thickness of DLC coating is around 150 nm and three different bias voltages were used for deposition. The tensile strength improved from 13.4 to 53.5% with the increasing of negative bias voltage. In addition, the deviation in strength also reduced significantly compared to bare SCS sample.

  1. Stress in tungsten carbide-diamond like carbon multilayer coatings

    NARCIS (Netherlands)

    Pujada, B.R.; Tichelaar, F.D.; Janssen, G.C.A.M.

    2007-01-01

    Tungsten carbide-diamond like carbon (WC-DLC) multilayer coatings have been prepared by sputter deposition from a tungsten-carbide target and periodic switching on and off of the reactive acetylene gas flow. The stress in the resulting WC-DLC multilayers has been studied by substrate curvature.

  2. Electrochemical performances of diamond-like carbon coatings on carbon steel, stainless steel, and brass

    International Nuclear Information System (INIS)

    Hadinata, Samuel-Sudibyo; Lee, Ming-Tsung; Pan, Szu-Jung; Tsai, Wen-Ta; Tai, Chen-Yi; Shih, Chuan-Feng

    2013-01-01

    Diamond-like carbon (DLC) coatings have been deposited onto stainless steel, carbon steel and brass by plasma-enhanced chemical vapor deposition, respectively. Atomic arrangement, chemical structure, surface morphology and cross-section microstructure of the DLC coatings were examined by X-ray diffraction, Raman scattering spectroscopy and scanning electron microscopy. The electrochemical behaviors of the DLC coatings in 3.5 wt.% NaCl solution were investigated by performing an open circuit potential (OCP) measurement and a potentiodynamic polarization test. The experimental results showed that properly deposited DLC coatings could cause an increase of OCP by hundreds of millivolts and a reduction of anodic current density by several orders of magnitude as compared to that of the substrate. The results also demonstrated that electrochemical techniques could be used as tools to detect the soundness of the DLC coating by examining OCP and polarization curve, which varied with the form of defect and depended on the type of substrate. - Highlights: ► The substrate could affect the quality of diamond-like carbon (DLC) coating. ► Defect-free DLC coating exhibited extremely low anodic current density. ► The quality of DLC coating on metal could be evaluated by electrochemical test

  3. Electrochemical performances of diamond-like carbon coatings on carbon steel, stainless steel, and brass

    Energy Technology Data Exchange (ETDEWEB)

    Hadinata, Samuel-Sudibyo; Lee, Ming-Tsung [Department of Materials Science and Engineering, National Cheng Kung University, 1, Ta-Hsueh Road, Tainan 701, Taiwan (China); Pan, Szu-Jung [Ocean Energy Research Center, Tainan Hydraulics Laboratory, National Cheng Kung University, 1, Ta-Hsueh Road, Tainan 701, Taiwan (China); Tsai, Wen-Ta, E-mail: wttsai@mail.ncku.edu.tw [Department of Materials Science and Engineering, National Cheng Kung University, 1, Ta-Hsueh Road, Tainan 701, Taiwan (China); Ocean Energy Research Center, Tainan Hydraulics Laboratory, National Cheng Kung University, 1, Ta-Hsueh Road, Tainan 701, Taiwan (China); Tai, Chen-Yi [Ocean Energy Research Center, Tainan Hydraulics Laboratory, National Cheng Kung University, 1, Ta-Hsueh Road, Tainan 701, Taiwan (China); Shih, Chuan-Feng [Ocean Energy Research Center, Tainan Hydraulics Laboratory, National Cheng Kung University, 1, Ta-Hsueh Road, Tainan 701, Taiwan (China); Department of Electrical Engineering, National Cheng Kung University, 1, Ta-Hsueh Road, Tainan 701, Taiwan (China)

    2013-02-01

    Diamond-like carbon (DLC) coatings have been deposited onto stainless steel, carbon steel and brass by plasma-enhanced chemical vapor deposition, respectively. Atomic arrangement, chemical structure, surface morphology and cross-section microstructure of the DLC coatings were examined by X-ray diffraction, Raman scattering spectroscopy and scanning electron microscopy. The electrochemical behaviors of the DLC coatings in 3.5 wt.% NaCl solution were investigated by performing an open circuit potential (OCP) measurement and a potentiodynamic polarization test. The experimental results showed that properly deposited DLC coatings could cause an increase of OCP by hundreds of millivolts and a reduction of anodic current density by several orders of magnitude as compared to that of the substrate. The results also demonstrated that electrochemical techniques could be used as tools to detect the soundness of the DLC coating by examining OCP and polarization curve, which varied with the form of defect and depended on the type of substrate. - Highlights: ► The substrate could affect the quality of diamond-like carbon (DLC) coating. ► Defect-free DLC coating exhibited extremely low anodic current density. ► The quality of DLC coating on metal could be evaluated by electrochemical test.

  4. Surface analytical investigation of diamond coatings and nucleation processes by secondary ion mass spectrometry

    International Nuclear Information System (INIS)

    Steiner, R.

    1993-10-01

    Imaging SIMS for the investigation of substrate surfaces: the influence of the substrate surface on diamond nucleation is a major topic in the investigation of the chemical vapour deposition (CVD) of diamond. It is well known that the nucleation density can be enhanced by scratching the substrate surface with abrasive powders. Diamond can nucleate at scratches or at residues of the polishing material. In the present work the surface of refractory metals (Mo, Nb, Ta, W) polished with silicon carbide and diamond powder is studied by imaging (2- or 3-D) secondary ion mass spectrometry (SIMS). In first experiments the distribution of SiC and/or diamond residues after polishing was determined. The reaction of diamond with the substrate during heating to deposition temperatures was investigated. Investigation of WC/Co hardmetal substrates: it is well known that Co contained in the binder phase of the hard metal inhibits a strong adhesion between the diamond film and the substrate, which is need for an application as cutting tool. Several attempts to improve the adhesion have been reported up to now. In this work a pre-treatment procedure leading to the formation of Co compounds (borides and silicides) which are stable under diamond deposition conditions were investigated. Furthermore, the application of intermediate sputter layers consisting of chromium and titanium were studied. Investigation of P-doped diamond coatings: in the quaternary phase diagram C-P-B-N exist some phases with diamond structure and superhard phases (e.g BP, c-BN). Also a hypothetical superhard phase of the composition C 3 N 4 is predicted. A scientific objective is the synthesis of such phases by chemical vapour deposition. An increase of the phosphorus concentration effects a distinct change in the morphology of the deposited coatings. A major advantage of SIMS is that the concentration profiles can be measured through the whole film, due to the sputter removal of the sample, and the interface

  5. SiC interlayer by laser-cladding on WC-Co substrates for CVD diamond deposition

    Energy Technology Data Exchange (ETDEWEB)

    Contin, Andre; Fraga, Mariana Amorim; Vieira, Jose; Trava-Airoldi, Vladimir Jesus; Corat, Evaldo Jose, E-mail: andrecontin@yahoo.com.br [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil); Campos, Raonei Alves [Universidade Federal do Sul e Sudeste do Para (UNIFESSPA), Belem, PA (Brazil); Vasconcelos, Getulio [Instituto de Estudos Avancados (IEA), Sao Jose dos Campos, SP (Brazil)

    2016-07-01

    Full text: Despite their huge industrial potential and commercial interest, the direct diamond coating on cemented carbide (WC-Co) is limited, mainly because of the catalytic effect of Cobalt (Co) and the high difference in thermal expansion coefficient [1]. This results in poor adherence between diamond and WC-Co. In addition, the low diamond film adhesion to the cemented carbide useless for machining applications. Removal of Co binder from the substrate surface by superficial etching is one of the techniques used to improve the adhesion between diamond and WC-Co. For the present study, diamond films were deposited on WC-Co substrates with an intermediate barrier to block the Co diffusion to the surface substrate. The laser cladding process produced the SiC barrier, in which a powder layer is melted by a laser irradiation to create the coating on the substrate. The use of laser cladding is the novel method for an intermediate barrier for cemented carbides. The advantages of laser cladding include a faster processing speed, precision, versatility. We reported the application of pretreatment method called ESND (Electrostatic self-assembly seeding of nanocrystalline diamond). The nucleation density was around 10{sup 11}part/cm{sup 2}. Diamond films were grown by Hot Filament Chemical Vapor Deposition. Characterization of samples included Field Emission Gun-Scanning Electron Microscopy (FEG-SEM), Energy Dispersive X-ray (EDX), X-ray diffraction (XRD) and Raman Scattering Spectroscopy. Results showed that laser irradiation formed stable Co compounds in the interfacial barrier. It is because nucleation and good quality of diamond film since the cobalt are no longer free to migrate to the surface during the CVD diamond deposition. Reference: [1] Y. X. Cui, B. Shen, F. H. Sun. Diamond deposition on WC–Co substrate with amorphous SiC interlayer, Surface Engineering, 30, (2014) 237-243. (author)

  6. Micro-texturing into DLC/diamond coated molds and dies via high density oxygen plasma etching

    Directory of Open Access Journals (Sweden)

    Yunata Ersyzario Edo

    2015-01-01

    Full Text Available Diamond-Like Carbon (DLC and Chemical Vapor Deposition (CVD-diamond films have been widely utilized not only as a hard protective coating for molds and dies but also as a functional substrate for bio-MEMS/NEMS. Micro-texturing into these hard coated molds and dies provides a productive tool to duplicate the original mother micro-patterns onto various work materials and to construct any tailored micro-textures for sensors and actuators. In the present paper, the high density oxygen plasma etching method is utilized to make micro-line and micro-groove patterns onto the DLC and diamond coatings. Our developing oxygen plasma etching system is introduced together with characterization on the plasma state during etching. In this quantitative plasma diagnosis, both the population of activated species and the electron and ion densities are identified through the emissive light spectroscopy and the Langmuir probe method. In addition, the on-line monitoring of the plasmas helps to describe the etching process. DLC coated WC (Co specimen is first employed to describe the etching mechanism by the present method. Chemical Vapor Deposition (CVD diamond coated WC (Co is also employed to demonstrate the reliable capacity of the present high density oxygen plasma etching. This oxygen plasma etching performance is discussed by comparison of the etching rates.

  7. Diamond film deposition on WC–Co and steel substrates with a CrN interlayer for tribological applications

    International Nuclear Information System (INIS)

    Chandran, Maneesh; Hoffman, Alon

    2016-01-01

    The most renowned property of diamond is its exceptional hardness. By depositing diamond films on tungsten carbide (WC–Co) and steel substrates, the hardness of diamond can be combined with the toughness of these materials, resulting in an excellent wear resistance material for tribological applications. However, poor adhesion of diamond coating on these substrates leads to a lesser lifetime for the diamond coated tools than expected. The prime reasons for the lack of proper adhesion are the preferential formation of graphitic layer at the interface due to the catalytic activities of cobalt/iron and the interfacial residual stresses due to the mismatch in thermal expansion coefficients of diamond (1.5  ×  10 −6 K −1 ) and WC–Co (5.2  ×  10 −6 K −1 ) or steel (12  ×  10 −6 K −1 ). In this review, we discuss the possibility of using a Cr–N interlayer as a diffusion barrier to prevent the catalytic activities of cobalt/iron and also to relax the interfacial residual stresses to some extent to enhance the adhesion of diamond coatings on these substrates. An overview of the most pertinent results of the last two decades, including the recent progress is introduced. We describe in detail how the Cr–N interlayer with the desired properties is fabricated. We give a concise overview of diamond deposition process, including the methods to vary the grain size from microcrystalline to nanocrystalline, which are suitable for some tribological applications. We describe in detail on surface and interface analysis, residual stress measurements, assessment adhesion strength and tribological performance of diamond coated WC–Co and steel substrates using various characterization techniques. We conclude by highlighting the current progress and future perspectives of diamond coatings on these substrates for tribological applications. (topical review)

  8. Characterization and development of diamond-like carbon coatings for storing ultracold neutrons

    CERN Document Server

    Grinten, M G D; Shiers, D; Baker, C A; Green, K; Harris, P G; Iaydjiev, P S; Ivanov, S N; Geltenbort, P

    1999-01-01

    In order to determine the suitability of diamond-like carbon (DLC) as a material for storing ultracold neutrons to use in neutron electric-dipole moment (EDM) experiments, a number of tests on DLC coatings have been performed. Thin DLC layers deposited on quartz and aluminium substrates by chemical vapour deposition have been characterised by neutron transmission, neutron reflectometry, electron microscopy and neutron and mercury storage and depolarisation lifetime measurements. Two types of DLC have been compared; DLC made by chemical vapour deposition from natural methane and DLC made by chemical vapour deposition from deuterated methane. With these samples we determined the density, hydrogen concentration and Fermi potential of the coatings. DLC coatings made from deuterated methane are now successfully being used in an experiment to measure the EDM of the neutron.

  9. Characterization and development of diamond-like carbon coatings for storing ultracold neutrons

    International Nuclear Information System (INIS)

    Grinten, M.G.D. van der; Pendlebury, J.M.; Shiers, D.; Baker, C.A.; Green, K.; Harris, P.G.; Iaydjiev, P.S.; Ivanov, S.N.; Geltenbort, P.

    1999-01-01

    In order to determine the suitability of diamond-like carbon (DLC) as a material for storing ultracold neutrons to use in neutron electric-dipole moment (EDM) experiments, a number of tests on DLC coatings have been performed. Thin DLC layers deposited on quartz and aluminium substrates by chemical vapour deposition have been characterised by neutron transmission, neutron reflectometry, electron microscopy and neutron and mercury storage and depolarisation lifetime measurements. Two types of DLC have been compared; DLC made by chemical vapour deposition from natural methane and DLC made by chemical vapour deposition from deuterated methane. With these samples we determined the density, hydrogen concentration and Fermi potential of the coatings. DLC coatings made from deuterated methane are now successfully being used in an experiment to measure the EDM of the neutron

  10. Tribological Characteristics and Applications of Superhard Coatings: CVD Diamond, DLC, and c-BN

    Science.gov (United States)

    Miyoshi, Kazuhisa; Murakawa, Masao; Watanabe, Shuichi; Takeuchi, Sadao; Wu, Richard L. C.

    1999-01-01

    Results of fundamental research on the tribological properties of chemical-vapor-deposited (CVD) diamond, diamondlike carbon, and cubic boron nitride films in sliding contact with CVD diamond in ultrahigh vacuum, dry nitrogen, humid air, and water are discussed. Furthermore, the actual and potential applications of the three different superhard coatings in the field of tribology technology, particularly for wear parts and tools, are reviewed.

  11. Laser reflection spot as a pattern in a diamond coating – a microscopic study

    Directory of Open Access Journals (Sweden)

    GORDANA S. RISTIĆ

    2009-07-01

    Full Text Available Diamond coatings were deposited by the synchronous and coupled action of a hot filament CVD method and a pulsed CO2 laser in spectro-absorbing and spectro-non-absorbing diamond precursor atmospheres. The obtained coatings were structured/patterned, i.e., they were comprised of uncovered, bare locations. An extra effect observed only in the spectro-active diamond precursor atmosphere was the creation of another laser spot in the coating – a reflection spot. In order to establish the practical usability of the latter one, extensive microscopic investigations were performed with consideration of the morphology changes in the spot of the direct laser beam. Normal incidence SEM images of this spot showed a smooth surface, without any pulse radiation damage. AFM imaging revealed the actual surface condition and gave precise data on the surface characteristics.

  12. Diamond-coated probe head for measurements in the deep SOL and beyond

    DEFF Research Database (Denmark)

    Schrittwieser, R.; Xu, G. S.; Yan, Ning

    We have tested two cylindrical graphite probe heads coated by a layer of electrically isolating UNCD (Ultra Nano-Crystalline Diamond) using a CVD (Chemical Vapour Deposition) method. The probe heads were mounted on the reciprocating probe manipulator of the Experimental Advanced Superconducting T...

  13. Chemical Vapor-Deposited (CVD) Diamond Films for Electronic Applications

    Science.gov (United States)

    1995-01-01

    Diamond films have a variety of useful applications as electron emitters in devices such as magnetrons, electron multipliers, displays, and sensors. Secondary electron emission is the effect in which electrons are emitted from the near surface of a material because of energetic incident electrons. The total secondary yield coefficient, which is the ratio of the number of secondary electrons to the number of incident electrons, generally ranges from 2 to 4 for most materials used in such applications. It was discovered recently at the NASA Lewis Research Center that chemical vapor-deposited (CVD) diamond films have very high secondary electron yields, particularly when they are coated with thin layers of CsI. For CsI-coated diamond films, the total secondary yield coefficient can exceed 60. In addition, diamond films exhibit field emission at fields orders of magnitude lower than for existing state-of-the-art emitters. Present state-of-the-art microfabricated field emitters generally require applied fields above 5x10^7 V/cm. Research on field emission from CVD diamond and high-pressure, high-temperature diamond has shown that field emission can be obtained at fields as low as 2x10^4 V/cm. It has also been shown that thin layers of metals, such as gold, and of alkali halides, such as CsI, can significantly increase field emission and stability. Emitters with nanometer-scale lithography will be able to obtain high-current densities with voltages on the order of only 10 to 15 V.

  14. Plasma spraying method for forming diamond and diamond-like coatings

    Science.gov (United States)

    Holcombe, Cressie E.; Seals, Roland D.; Price, R. Eugene

    1997-01-01

    A method and composition for the deposition of a thick layer (10) of diamond or diamond-like material. The method includes high temperature processing wherein a selected composition (12) including at least glassy carbon is heated in a direct current plasma arc device to a selected temperature above the softening point, in an inert atmosphere, and is propelled to quickly quenched on a selected substrate (20). The softened or molten composition (18) crystallizes on the substrate (20) to form a thick deposition layer (10) comprising at least a diamond or diamond-like material. The selected composition (12) includes at least glassy carbon as a primary constituent (14) and may include at least one secondary constituent (16). Preferably, the secondary constituents (16) are selected from the group consisting of at least diamond powder, boron carbide (B.sub.4 C) powder and mixtures thereof.

  15. Development of diamond coated tool and its performance in ...

    Indian Academy of Sciences (India)

    Unknown

    Mechanical Engineering Department, Indian Institute of Technology, Kharagpur 721 302, India ... chemical inertness of diamond coating towards the work material, did not show any .... CVD diamond coated carbide tools, Ph D Thesis, Indian.

  16. Ultrananocrystalline diamond film as a wear resistant and protective coating for mechanical seal applications

    International Nuclear Information System (INIS)

    Sumant, A.V.; Krauss, A.R.; Gruen, D.M.; Auciello, O.; Erdemir, A.; Williams, M.; Artiles, A.F.; Adams, W.

    2005-01-01

    Mechanical shaft seals used in pumps are critically important to the safe operation of the paper, pulp, and chemical process industry, as well as petroleum and nuclear power plants. Specifically, these seals prevent the leakage of toxic gases and hazardous chemicals to the environment and final products from the rotating equipment used in manufacturing processes. Diamond coatings have the potential to provide negligible wear, ultralow friction, and high corrosion resistance for the sliding surfaces of mechanical seals, because diamond exhibits outstanding tribological, physical, and chemical properties. However, diamond coatings produced by conventional chemical vapor deposition (CVD) exhibit high surface roughness (R a ≥ 1 μm), which results in high wear of the seal counterface, leading to premature seal failure. To avoid this problem, we have developed an ultrananocrystalline diamond (UNCD) film formed by a unique CH 4 /Ar microwave plasma CVD method. This method yields extremely smooth diamond coatings with surface roughness R a = 20-30 nm and an average grain size of 2-5 nm. We report the results of a systematic test program involving uncoated and UNCD-coated SiC shaft seals. Results confirmed that the UNCD-coated seals exhibited neither measurable wear nor any leakage during long-duration tests that took 21 days to complete. In addition, the UNCD coatings reduced the frictional torque for seal rotation by five to six times compared with the uncoated seals. This work promises to lead to rotating shaft seals with much improved service life, reduced maintenance cost, reduced leakage of environmentally hazardous materials, and increased energy savings. This technology may also have many other tribological applications involving rolling or sliding contacts.

  17. Direct Coating of Nanocrystalline Diamond on Steel

    Science.gov (United States)

    Tsugawa, Kazuo; Kawaki, Shyunsuke; Ishihara, Masatou; Hasegawa, Masataka

    2012-09-01

    Nanocrystalline diamond films have been successfully deposited on stainless steel substrates without any substrate pretreatments to promote diamond nucleation, including the formation of interlayers. A low-temperature growth technique, 400 °C or lower, in microwave plasma chemical vapor deposition using a surface-wave plasma has cleared up problems in diamond growth on ferrous materials, such as the surface graphitization, long incubation time, substrate softening, and poor adhesion. The deposited nanocrystalline diamond films on stainless steel exhibit good adhesion and tribological properties, such as a high wear resistance, a low friction coefficient, and a low aggression strength, at room temperature in air without lubrication.

  18. Cold cathodes on ultra-dispersed diamond base

    International Nuclear Information System (INIS)

    Alimova, A.N.; Zhirnov, V.V.; Chubun, N.N.; Belobrov, P.I.

    1998-01-01

    Prospects of application of nano diamond powders for fabrication of cold cathodes are discussed.Cold cathodes based on silicon pointed structures with nano diamond coatings were prepared.The deposition technique of diamond coating was dielectrophoresis from suspension of nano diamond powder in organic liquids.The cathodes were tested in sealed prototypes of vacuum electronic devices

  19. High vacuum tribology of polycrystalline diamond coatings

    Indian Academy of Sciences (India)

    Polycrystalline diamond coatings; hot filament CVD; high vacuum tribology. 1. Introduction .... is a characteristic of graphite. We mark the (diamond ... coefficient of friction due to changes in substrate temperature. The average coefficient of.

  20. "Diamond" over-coated Microstrip Gas Chambers for high rate operation

    CERN Document Server

    Barr, A J; Bouclier, Roger; Capéans-Garrido, M; Dominik, Wojciech; Hoch, M; Manzin, G; Million, Gilbert; Ropelewski, Leszek; Sauli, Fabio; Sharma, A

    1997-01-01

    We describe the recent developments on the diamond-like carbon (DLC) over-coated Microstrip Gas Chambers made on drawn glass substrates. MSGC surface coating with thin DLC layer of stable and controlled resistivity was proposed to overcome the limitation of detector operation due to surface charging-up under avalanches. This brings also advantages for the detector manufacturing technology. The thin layer, deposited on top of a manufactured MSGC (over-coating), demonstrates excellent mechanical properties and very good stability. We report on recent measurements with DLC over-coated MSGCs of various surface resistivities (ranging from 1013W/r to 1016W/r) on D-263 and AF45 glass substrates. Over-coated MSGCs exhibit good rate capability for the resistivity of the surface around 1015W/r. Stable operation up to 50 mC/cm of accumulated charge from avalanches has been demonstrated.

  1. The potential use of diamond coated tungsten tips as a field ionisation source

    Energy Technology Data Exchange (ETDEWEB)

    Brown, A.; Prawer, S.; Legge, G.J.F.; Kostidis, L.I. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1996-12-31

    Tungsten tips are convenient for use in a high brightness gaseous phase field ionisation source. However, the lifetime of these tips is not adequate for practical use. The authors are investigating whether coating tungsten tips with diamond using Chemical Vapor Deposition (CVD) will improve the practicality of using these tips by an improvement in longevity of the source and/or an improvement in brightness due to the effects of the property of negative electron affinity which has been observed on CVD diamond. 1 ref.

  2. The potential use of diamond coated tungsten tips as a field ionisation source

    Energy Technology Data Exchange (ETDEWEB)

    Brown, A; Prawer, S; Legge, G J.F.; Kostidis, L I [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1997-12-31

    Tungsten tips are convenient for use in a high brightness gaseous phase field ionisation source. However, the lifetime of these tips is not adequate for practical use. The authors are investigating whether coating tungsten tips with diamond using Chemical Vapor Deposition (CVD) will improve the practicality of using these tips by an improvement in longevity of the source and/or an improvement in brightness due to the effects of the property of negative electron affinity which has been observed on CVD diamond. 1 ref.

  3. Plasma Assisted Chemical Vapour Deposition – Technological Design Of Functional Coatings

    Directory of Open Access Journals (Sweden)

    Januś M.

    2015-06-01

    Full Text Available Plasma Assisted Chemical Vapour Deposition (PA CVD method allows to deposit of homogeneous, well-adhesive coatings at lower temperature on different substrates. Plasmochemical treatment significantly impacts on physicochemical parameters of modified surfaces. In this study we present the overview of the possibilities of plasma processes for the deposition of diamond-like carbon coatings doped Si and/or N atoms on the Ti Grade2, aluminum-zinc alloy and polyetherketone substrate. Depending on the type of modified substrate had improved the corrosion properties including biocompatibility of titanium surface, increase of surface hardness with deposition of good adhesion and fine-grained coatings (in the case of Al-Zn alloy and improving of the wear resistance (in the case of PEEK substrate.

  4. A study of the performance and properties of diamond like carbon (DLC) coatings deposited by plasma chemical vapor deposition (CVD) for two stroke engine components

    Energy Technology Data Exchange (ETDEWEB)

    Tither, D. [BEP Grinding Ltd., Manchester (United Kingdom); Ahmed, W.; Sarwar, M.; Penlington, R. [Univ. of Northumbria, Newcastle-upon-Tyne (United Kingdom)

    1995-12-31

    Chemical vapor deposition (CVD) using microwave and RF plasma is arguably the most successful technique for depositing diamond and diamond like carbon (DLC) films for various engineering applications. However, the difficulties of depositing diamond are nearly as extreme as it`s unique combination of physical, chemical and electrical properties. In this paper, the modified low temperature plasma enhanced CVD system is described. The main focus of this paper will be work related to deposition of DLC on metal matrix composite materials (MMCs) for application in two-stroke engine components and results will be presented from SEM, mechanical testing and composition analysis studies. The authors have demonstrated the feasibility of depositing DLC on MMCs for the first time using a vacuum deposition process.

  5. Large area diamond-like carbon coatings by ion implantation

    International Nuclear Information System (INIS)

    McCabe, A.R.; Proctor, G.; Jones, A.M.; Bull, S.J.; Chivers, D.J.

    1993-01-01

    Diamond-like Carbon (DLC) coatings have been deposited onto large geometry components in the Harwell Blue Tank ion implantation facility. To modify the substrate surface and to crack the low vapour pressure oil which is evaporated and condensed onto the surface, a 40 Kev nitrogen ion bucket ion source is used. The coating of areas up to 1 metre in diameter is common and with component manipulation larger areas may be coated. Since the component temperature never exceeds 80 o C during the process, a wide range of materials may be coated including specialist tool steels and even certain high density polymers. In order to produce hard wear resistant coatings with extremely low coefficients of friction (0.02-0.15) and a range of mechanical and electrical properties, various oil precursors have been investigated. The production and assessment of such coatings, including measurements of their tribiological performance, is presented. Applications for wear resistance, corrosion protection and electrically conducting coatings are discussed with examples drawn from engineering, electronics and biomedicine. (7 figures, 13 references). (UK)

  6. The versatility of hot-filament activated chemical vapor deposition

    International Nuclear Information System (INIS)

    Schaefer, Lothar; Hoefer, Markus; Kroeger, Roland

    2006-01-01

    In the field of activated chemical vapor deposition (CVD) of polycrystalline diamond films, hot-filament activation (HF-CVD) is widely used for applications where large deposition areas are needed or three-dimensional substrates have to be coated. We have developed processes for the deposition of conductive, boron-doped diamond films as well as for tribological crystalline diamond coatings on deposition areas up to 50 cm x 100 cm. Such multi-filament processes are used to produce diamond electrodes for advanced electrochemical processes or large batches of diamond-coated tools and parts, respectively. These processes demonstrate the high degree of uniformity and reproducibility of hot-filament CVD. The usability of hot-filament CVD for diamond deposition on three-dimensional substrates is well known for CVD diamond shaft tools. We also develop interior diamond coatings for drawing dies, nozzles, and thread guides. Hot-filament CVD also enables the deposition of diamond film modifications with tailored properties. In order to adjust the surface topography to specific applications, we apply processes for smooth, fine-grained or textured diamond films for cutting tools and tribological applications. Rough diamond is employed for grinding applications. Multilayers of fine-grained and coarse-grained diamond have been developed, showing increased shock resistance due to reduced crack propagation. Hot-filament CVD is also used for in situ deposition of carbide coatings and diamond-carbide composites, and the deposition of non-diamond, silicon-based films. These coatings are suitable as diffusion barriers and are also applied for adhesion and stress engineering and for semiconductor applications, respectively

  7. Chemical vapor deposition of diamond onto iron based substrates. The use of barrier layers

    International Nuclear Information System (INIS)

    Weiser, P.S.; Prawer, S.

    1995-01-01

    When Fe is exposed to the plasma environment suitable for the chemical vapor deposition (CVD) of diamond, the surface is rapidly covered with a thick layer graphitic soot and C swiftly diffuses into the Fe substrate. Once the soot reaches a critical thickness, diamond films nucleate and grow on top of it. However, adhesion of the film to the substrate is poor due to the lack of structural integrity of the soot layer, A thin coating of TiN on the Fe can act to prevent diffusion and soot formation. Diamond readily grows upon the TiN via an a-C interface layer, but the a-C/TiN interface is weak and delamination occurs at this interface. In order to try and improve the adhesion, the use of a high dose Ti implant was investigated to replace the TiN coating. 7 refs., 6 figs

  8. Selective deposition of polycrystalline diamond films using photolithography with addition of nanodiamonds as nucleation centers

    International Nuclear Information System (INIS)

    Okhotnikov, V V; Linnik, S A; Gaidaichuk, A V; Shashev, D V; Nazarova, G Yu; Yurchenko, V I

    2016-01-01

    A new method of selective deposition of polycrystalline diamond has been developed and studied. The diamond coatings with a complex, predetermined geometry and resolution up to 5 μm were obtained. A high density of polycrystallites in the coating area was reached (up to 32·10 7 pcs/cm 2 ). The uniformity of the film reached 100%, and the degree of the surface contamination by parasitic crystals did not exceed 2%. The technology was based on the application of the standard photolithography with an addition of nanodiamond suspension into the photoresist that provided the creation of the centers of further nucleation in the areas which require further overgrowth. The films were deposited onto monocrystalline silicon substrates using the method of “hot filaments” in the CVD reactor. The properties of the coating and the impact of the nanodiamond suspension concentration in the photoresist were also studied. The potential use of the given method includes a high resolution, technological efficiency, and low labor costs compared to the standard methods (laser treatment, chemical etching in aggressive environments,). (paper)

  9. Selective deposition of polycrystalline diamond films using photolithography with addition of nanodiamonds as nucleation centers

    Science.gov (United States)

    Okhotnikov, V. V.; Linnik, S. A.; Gaidaichuk, A. V.; Shashev, D. V.; Nazarova, G. Yu; Yurchenko, V. I.

    2016-02-01

    A new method of selective deposition of polycrystalline diamond has been developed and studied. The diamond coatings with a complex, predetermined geometry and resolution up to 5 μm were obtained. A high density of polycrystallites in the coating area was reached (up to 32·107 pcs/cm2). The uniformity of the film reached 100%, and the degree of the surface contamination by parasitic crystals did not exceed 2%. The technology was based on the application of the standard photolithography with an addition of nanodiamond suspension into the photoresist that provided the creation of the centers of further nucleation in the areas which require further overgrowth. The films were deposited onto monocrystalline silicon substrates using the method of “hot filaments” in the CVD reactor. The properties of the coating and the impact of the nanodiamond suspension concentration in the photoresist were also studied. The potential use of the given method includes a high resolution, technological efficiency, and low labor costs compared to the standard methods (laser treatment, chemical etching in aggressive environments,).

  10. Comprehensive Evaluation of the Properties of Nanocrystalline Diamond Coatings Grown Using CVD with E/H Field Glow Discharge Stabilization

    Directory of Open Access Journals (Sweden)

    Iu. Nasieka

    2015-01-01

    Full Text Available The nanocrystalline diamond films (coatings were prepared using the plasma enhanced chemical vapor deposition (PECVD technique. In this method, direct current (DC glow discharge in the crossed E/H fields was used to activate the gas phase. The diamond coatings were deposited from the working gas mixture CH4/H2 with addition of nitrogen in various concentrations. It was ascertained that addition of N2 to the working gas mixture leads to reduction in the sizes of diamond grains as well as to the substantial decrease in the resistivity of the studied films. The electrophysical data are in good agreement with the changes induced by varying the N2 content in the Raman scattering spectra. The increase in the N2 concentration causes significant lowering of the crystalline diamond related peak and increase in the intensity of the peaks related to the sp2-bonded carbon. These changes in the spectra indicate significant disordering of the structure of prepared films and its uniformity in the nanodiamond film volume. With the great possibility, it is associated with a decrease in the sizes of diamond crystalline grains and tendency of NCD film to amorphization.

  11. D.C. Arcjet Diamond Deposition

    Science.gov (United States)

    Russell, Derrek Andrew

    1995-01-01

    Polycrystalline diamond films synthesized by a D.C. (direct current) arcjet device was reported for the first time in 1988. This device is capable of higher diamond growth rates than any other form of diamond CVD (chemical vapor deposition) process due to its inherent versatility with regard to the enthalpy and fluid properties of the diamond-depositing vapor. Unfortunately, the versatility of this type of device is contrasted by many difficulties such as arc stability and large heat fluxes which make applying it toward diamond deposition a difficult problem. The purpose of this work was to convert the dc arcjet, which is primarily a metallurgical device, into a commercially viable diamond CVD process. The project was divided into two parts: process development and diagnostics. The process development effort concentrated on the certain engineering challenges. Among these was a novel arcjet design that allowed the carbon-source gas to be injected downstream of the tungsten cathode while still facilitating mixture with the main gas feed. Another engineering accomplishment was the incorporation of a water -cooled substrate cooler/spinner that maintained the substrate at the proper temperature, provided the substrate with a large thermal time constant to reduce thermal shock of the diamond film, and enabled the system to achieve a four -inch diameter growth area. The process diagnostics effort concentrated on measurements aimed at developing a fundamental understanding of the properties of the plasma jet such as temperature, plasma density, Mach number, pressure at the substrate, etc. The plasma temperature was determined to be 5195 K by measuring the rotational temperature of C _2 via optical emission spectroscopy. The Mach number of the plasma jet was determined to be ~6.0 as determined by the ratio of the stagnation pressures before and after the shock wave in the plasma jet. The C_2 concentration in the plasma jet was determined to be {~10 }^{12} cm^ {-3} by

  12. Fabrication of nitrogen-containing diamond-like carbon film by filtered arc deposition as conductive hard-coating film

    Science.gov (United States)

    Iijima, Yushi; Harigai, Toru; Isono, Ryo; Imai, Takahiro; Suda, Yoshiyuki; Takikawa, Hirofumi; Kamiya, Masao; Taki, Makoto; Hasegawa, Yushi; Tsuji, Nobuhiro; Kaneko, Satoru; Kunitsugu, Shinsuke; Habuchi, Hitoe; Kiyohara, Shuji; Ito, Mikio; Yick, Sam; Bendavid, Avi; Martin, Phil

    2018-01-01

    Diamond-like carbon (DLC) films, which are amorphous carbon films, have been used as hard-coating films for protecting the surface of mechanical parts. Nitrogen-containing DLC (N-DLC) films are expected as conductive hard-coating materials. N-DLC films are expected in applications such as protective films for contact pins, which are used in the electrical check process of integrated circuit chips. In this study, N-DLC films are prepared using the T-shaped filtered arc deposition (T-FAD) method, and film properties are investigated. Film hardness and film density decreased when the N content increased in the films because the number of graphite structures in the DLC film increased as the N content increased. These trends are similar to the results of a previous study. The electrical resistivity of N-DLC films changed from 0.26 to 8.8 Ω cm with a change in the nanoindentation hardness from 17 to 27 GPa. The N-DLC films fabricated by the T-FAD method showed high mechanical hardness and low electrical resistivity.

  13. Graphitization of diamond with a metallic coating on ferritic matrix

    International Nuclear Information System (INIS)

    Cabral, Stenio Cavalier; Oliveira, Hellen Cristine Prata de; Filgueira, Marcello

    2010-01-01

    Iron is a strong catalyst of graphitization of diamonds. This graphitization occurs mainly during the processing of composites - conventional sintering or hot pressing, and during cutting operations. Aiming to avoid or minimize this deleterious effect, there is increasing use of diamond coated with metallic materials in the production of diamond tools processed via powder metallurgy. This work studies the influence of Fe on diamond graphitization diamond-coated Ti after mixing of Fe-diamonds, hot pressing parameters were performed with 3 minutes/35MPa/900 deg C - this is the condition of pressing hot used in industry for production of diamond tools. Microstructural features were observed by SEM, diffusion of Fe in diamond was studied by EDS. Graphitization was analyzed by X-ray diffraction and Raman spectroscopy. It was found that Fe not activate graphitization on the diamond under the conditions of hot pressing. (author)

  14. Nanocrystalline diamond coatings for cutting operations; Nanokristalline Diamantschichten fuer die Zerspanung

    Energy Technology Data Exchange (ETDEWEB)

    Frank, M.; Breidt, D.; Cremer, R. [CemeCon AG, Wuerselen (Germany). Technology

    2006-06-15

    The history of the CVD diamond synthesis goes back into the fifties. However, the scientific and economical potential was only gradually recognized. In the eighties intensive world-wide research on CVD diamond synthesis and applications were launched. Industrial products, especially diamond-coated cutting tools, were introduced to the market in the middle of the nineties. The article shows the latest developments in this area, which comprises nanocrystalline diamond coating structures. (orig.)

  15. Electrochemical characterization of doped diamond-coated carbon fibers at different boron concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, E.C. [INPE, CP 515, Sao Jose dos Campos, SP 12201-970 (Brazil)]. E-mail: erica@las.inpe.br; Diniz, A.V. [INPE, CP 515, Sao Jose dos Campos, SP 12201-970 (Brazil); Trava-Airoldi, V.J. [INPE, CP 515, Sao Jose dos Campos, SP 12201-970 (Brazil); Ferreira, N.G. [CTA-Divisao de Materiais, Sao Jose dos Campos, SP 12228-904 (Brazil)

    2005-08-01

    Doped diamond films have been deposited on carbon fibers (felt) obtained from polyacrylonitrile at different levels of boron doping. For a successful coating of the fibers, an ultrasonic pretreatment in a bath of diamond powder dissolved in hexane was required. Films were grown on both sample sides, simultaneously, by hot filament-assisted chemical vapour deposition technique at 750 deg. C from a 0.5% H{sub 2}/CH{sub 4} mixture at a total pressure of 6.5 x 10{sup 3} Pa. Boron was obtained from H{sub 2} forced to pass through a bubbler containing B{sub 2}O{sub 3} dissolved in methanol. The doping level studied corresponds to films with acceptor concentrations in the range of 6.5 x 10{sup 18} to 1.5 x 10{sup 21} cm{sup -} {sup 3}, obtained from Mott-Schottky plots. Scanning electron microscopy analyses evidenced fibers totally covered with high quality polycrystalline boron-doped diamond film, also confirmed by Raman spectroscopy spectra. Diamond electrodes grown on carbon fibers demonstrated similar electrochemical behavior obtained from films on Si substrate, for ferri/ferrocyanide redox couple as a function of boron content. The boron content influences electrochemical surface area. A lower boron concentration provides a higher growth rate that results in a higher surface area.

  16. CVD diamond coatings on titanium : Characterisation by XRD techniques

    Energy Technology Data Exchange (ETDEWEB)

    Cappuccio, G [CNR, Frascati, Rome (Italy). Istituto di Strutturistica Chimica; [INFN-LNF, Frascati, Rome (Italy). Laboratorio Dafne Luce

    1996-09-01

    Here, the authors report an analysis carried out on diamond coatings on titanium substrates to show the potentially of x-ray diffraction techniques in the structural characterisation both of diamond thin films and of the other phases (TiC and TiH{sub 2}) present in the interfacial layer. It should be noted that the composition and microstructure of the interface layers strongly affect the characteristics of the diamond films, particularly adhesion, which is one of the most important elements determining the final quality of the coating.

  17. Tracing the Source of Borneo's Cempaka Diamond Deposit

    Science.gov (United States)

    White, L. T.; Graham, I.; Armstrong, R. A.; Hall, R.

    2014-12-01

    Several gem quality diamond deposits are found in paleo-alluvial deposits across Borneo. The source of the diamonds and their origin are enigmatic. They could have formed in Borneo and be derived from local sources, or they could be related to diamond deposits in NW Australia, and carried with the Southwest Borneo Block after it rifted from Australia in the Late Jurassic. We collected U-Pb isotopic data from detrital zircons from the Cempaka alluvial diamond deposit in southeast Borneo. Two thirds of the zircons that were dated crystallized between 75 Ma and 110 Ma. The other third are Triassic or older (223 Ma, 314-319 Ma, 353-367 Ma, 402-414 Ma, 474 Ma, 521 Ma, 549 Ma, 1135-1176 Ma, 1535 Ma, 2716 Ma). All of the Cretaceous zircons are angular, euhedral grains with minor evidence of mechanical abrasion. Considering their age and morphology they were likely derived from the nearby Schwaner Granites. The Triassic and older grains are rounded to semi-rounded and were likely derived from Australia before Borneo rifted from Gondwana. Some of the zircons have ages that resemble those of the Merlin and Argyle diamond deposits of Australia. The diamonds themselves have delicate resorption features and overgrowths that would potentially be destroyed with prolonged transport. Geochemical data collected from the diamonds implies they were associated with lamproite intrusions. Deep seismic lines and zircons from igneous rocks suggest SE Borneo, the East Java Sea and East Java are largely underlain by thick lithosphere rifted from NW Australia. Based on several lines of evidence, we propose that diamond-bearing lamproites intruded before rifting of SW Borneo from Australia, or after collision with Sundaland of SW Borneo and the East Java-West Sulawesi Blocks during the Cretaceous. Exposure of the source after the Late Cretaceous led to diamond accumulation in river systems that flowed from the Schwaner Mountains.

  18. Diamond-coated three-dimensional GaN micromembranes: effect of nucleation and deposition techniques

    Czech Academy of Sciences Publication Activity Database

    Ižák, Tibor; Vanko, G.; Babchenko, Oleg; Potocký, Štěpán; Marton, M.; Vojs, M.; Choleva, P.; Kromka, Alexander

    2015-01-01

    Roč. 252, č. 11 (2015), s. 2585-2590 ISSN 0370-1972 R&D Projects: GA ČR(CZ) GP14-16549P Institutional support: RVO:68378271 Keywords : diamond film * GaN micromembranes * microwave chemical vapour deposition * polymer-based nucleation Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.522, year: 2015

  19. Frictional and Optical Properties of Diamond-Like-Carbon Coatings on Polycarbonate

    International Nuclear Information System (INIS)

    Lin Zeng; Gao Ding; Ba Dechun; Wang Feng; Liu Chunming

    2013-01-01

    In this work, diamond-like-carbon (DLC) films were deposited onto polycarbonate (PC) substrates by radio-frequency plasma-enhanced chemical vapor deposition (RF PECVD), and silicon films were prepared between DLC and PC substrates by magnetron sputtering deposition so as to improve the adhesion of the DLC films. The deposited films were investigated by means of field-emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Subsequently, the following frictional and optical properties of the films were measured: the friction coefficient by using a ball-on-disk tribometer, the scratch hardness by using a nano-indenter, the optical transmittance by using a UV/visible spectrometer. The effects of incident power upon the frictional and optical properties of the films were investigated. Films deposited at low incident powers showed large optical gaps, which decreased with increasing incident power. The optical properties of DLC films correlated to the sp 2 content of the coatings. High anti-scratch properties were obtained at higher values of incident power. The anti-scratch properties of DLC films correlated to the sp 3 content of the coatings

  20. A novel radial anode layer ion source for inner wall pipe coating and materials modification--hydrogenated diamond-like carbon coatings from butane gas.

    Science.gov (United States)

    Murmu, Peter P; Markwitz, Andreas; Suschke, Konrad; Futter, John

    2014-08-01

    We report a new ion source development for inner wall pipe coating and materials modification. The ion source deposits coatings simultaneously in a 360° radial geometry and can be used to coat inner walls of pipelines by simply moving the ion source in the pipe. Rotating parts are not required, making the source ideal for rough environments and minimizing maintenance and replacements of parts. First results are reported for diamond-like carbon (DLC) coatings on Si and stainless steel substrates deposited using a novel 360° ion source design. The ion source operates with permanent magnets and uses a single power supply for the anode voltage and ion acceleration up to 10 kV. Butane (C4H10) gas is used to coat the inner wall of pipes with smooth and homogeneous DLC coatings with thicknesses up to 5 μm in a short time using a deposition rate of 70 ± 10 nm min(-1). Rutherford backscattering spectrometry results showed that DLC coatings contain hydrogen up to 30 ± 3% indicating deposition of hydrogenated DLC (a-C:H) coatings. Coatings with good adhesion are achieved when using a multiple energy implantation regime. Raman spectroscopy results suggest slightly larger disordered DLC layers when using low ion energy, indicating higher sp(3) bonds in DLC coatings. The results show that commercially interesting coatings can be achieved in short time.

  1. Frictional and mechanical properties of diamond-like carbon-coated orthodontic brackets.

    Science.gov (United States)

    Muguruma, Takeshi; Iijima, Masahiro; Brantley, William A; Nakagaki, Susumu; Endo, Kazuhiko; Mizoguchi, Itaru

    2013-04-01

    This study investigated the effects of a diamond-like carbon (DLC) coating on frictional and mechanical properties of orthodontic brackets. DLC films were deposited on stainless steel brackets using the plasma-based ion implantation/deposition (PBIID) method under two different atmospheric conditions. As-received metal brackets served as the control. Two sizes of stainless steel archwires, 0.018 inch diameter and 0.017 × 0.025 inch cross-section dimensions, were used for measuring static and kinetic friction by drawing the archwires through the bracket slots, using a mechanical testing machine (n = 10). The DLC-coated brackets were observed with a scanning electron microscope (SEM). Values of hardness and elastic modulus were obtained by nanoindentation testing (n = 10). Friction forces were compared by one-way analysis of variance and the Scheffé test. The hardness and elastic modulus of the brackets were compared using Kruskal-Wallis and Mann-Whitney U-tests. SEM photomicrographs showed DLC layers on the bracket surfaces with thickness of approximately 5-7 μm. DLC-coated brackets deposited under condition 2 showed significantly less static frictional force for the stainless steel wire with 0.017 × 0.025 inch cross-section dimensions than as-received brackets and DLC-coated brackets deposited under condition 1, although both DLC-coated brackets showed significantly less kinetic frictional force than as-received brackets. The hardness of the DLC layers was much higher than that of the as-received bracket surfaces. In conclusion, the surfaces of metal brackets can be successfully modified by the PBIID method to create a DLC layer, and the DLC-coating process significantly reduces frictional forces.

  2. Thermal applications of low-pressure diamond

    International Nuclear Information System (INIS)

    Haubner, R.; Lux, B.

    1997-01-01

    During the last decade several applications of low-pressure diamond were developed. Main products are diamond heat-spreaders using its high thermal conductivity, diamond windows with their high transparency over a wide range of wavelengths and wear resistant tool coatings because of diamonds superhardness. A short description of the most efficient diamond deposition methods (microwave, DC-glow discharge, plasma-jet and arc discharge) is given. The production and applications of diamond layers with high thermal conductivity will be described. Problems of reproducibility of diamond deposition, the influence of impurities, the heat conductivity in electronic packages, reliability and economical mass production will be discussed. (author)

  3. Functional foam coatings inside tubing and custom developed diamond ignition targets

    International Nuclear Information System (INIS)

    Dawedeit, Christoph

    2014-01-01

    The development of inertial confinement fusion targets requires new efficient ablator materials and characteristic temperature measurements during confinement. Here, an aerogel coating process is developed to coat inside spheres and cylinders. The characteristic emission spectrum of doped aerogel inside diamond targets is used as temperature gauge during confinement. Coatings inside metal cylinders confirmed the generality of the coating procedure. In addition artificial diamond is characterized which represents an interesting ablator material.

  4. Tracing the depositional history of Kalimantan diamonds by zircon provenance and diamond morphology studies

    Science.gov (United States)

    Kueter, Nico; Soesilo, Joko; Fedortchouk, Yana; Nestola, Fabrizio; Belluco, Lorenzo; Troch, Juliana; Wälle, Markus; Guillong, Marcel; Von Quadt, Albrecht; Driesner, Thomas

    2016-11-01

    Diamonds in alluvial deposits in Southeast Asia are not accompanied by indicator minerals suggesting primary kimberlite or lamproite sources. The Meratus Mountains in Southeast Borneo (Province Kalimantan Selatan, Indonesia) provide the largest known deposit of these so-called "headless" diamond deposits. Proposals for the origin of Kalimantan diamonds include the adjacent Meratus ophiolite complex, ultra-high pressure (UHP) metamorphic terranes, obducted subcontinental lithospheric mantle and undiscovered kimberlite-type sources. Here we report results from detailed sediment provenance analysis of diamond-bearing Quaternary river channel material and from representative outcrops of the oldest known formations within the Alino Group, including the diamond-bearing Campanian-Maastrichtian Manunggul Formation. Optical examination of surfaces of diamonds collected from artisanal miners in the Meratus area (247 stones) and in West Borneo (Sanggau Area, Province Kalimantan Barat; 85 stones) points toward a classical kimberlite-type source for the majority of these diamonds. Some of the diamonds host mineral inclusions suitable for deep single-crystal X-ray diffraction investigation. We determined the depth of formation of two olivines, one coesite and one peridotitic garnet inclusion. Pressure of formation estimates for the peridotitic garnet at independently derived temperatures of 930-1250 °C are between 4.8 and 6.0 GPa. Sediment provenance analysis includes petrography coupled to analyses of detrital garnet and glaucophane. The compositions of these key minerals do not indicate kimberlite-derived material. By analyzing almost 1400 zircons for trace element concentrations with laser ablation ICP-MS (LA-ICP-MS) we tested the mineral's potential as an alternative kimberlite indicator. The screening ultimately resulted in a small subset of ten zircons with a kimberlitic affinity. Subsequent U-Pb dating resulting in Cretaceous ages plus a detailed chemical reflection make

  5. Corrosion and Wear Behaviors of Cr-Doped Diamond-Like Carbon Coatings

    Science.gov (United States)

    Viswanathan, S.; Mohan, L.; Bera, Parthasarathi; Kumar, V. Praveen; Barshilia, Harish C.; Anandan, C.

    2017-08-01

    A combination of plasma-enhanced chemical vapor deposition and magnetron sputtering techniques has been employed to deposit chromium-doped diamond-like carbon (DLC) coatings on stainless steel, silicon and glass substrates. The concentrations of Cr in the coatings are varied by changing the parameters of the bipolar pulsed power supply and the argon/acetylene gas composition. The coatings have been studied for composition, morphology, surface nature, nanohardness, corrosion resistance and wear resistance properties. The changes in I D / I G ratio with Cr concentrations have been obtained from Raman spectroscopy studies. Ratio decreases with an increase in Cr concentration, and it has been found to increase at higher Cr concentration, indicating the disorder in the coating. Carbide is formed in Cr-doped DLC coatings as observed from XPS studies. There is a decrease in sp 3/ sp 2 ratios with an increase in Cr concentration, and it increases again at higher Cr concentration. Nanohardness studies show no clear dependence of hardness on Cr concentration. DLC coatings with lower Cr contents have demonstrated better corrosion resistance with better passive behavior in 3.5% NaCl solution, and corrosion potential is observed to move toward nobler (more positive) values. A low coefficient of friction (0.15) at different loads is observed from reciprocating wear studies. Lower wear volume is found at all loads on the Cr-doped DLC coatings. Wear mechanism changes from abrasive wear on the substrate to adhesive wear on the coating.

  6. Deposition and microstructure of Ti-containing diamond-like carbon nanocomposite films

    International Nuclear Information System (INIS)

    Yang, Won Jae; Sekino, Tohru; Shim, Kwang Bo; Niihara, Koichi; Auh, Keun Ho

    2005-01-01

    Ti-containing diamond-like carbon (DLC) films were deposited by plasma decomposition of CH 4 /Ar gas mixtures with an introduction of tetrakis(dimethylamino)titanium (TDMAT, Ti[(CH 3 ) 2 N] 4 ), which was used as a precursor of titanium. The films deposited were found to be nanocomposite coatings consisting of TiN nanocrystalline clusters and amorphous hydrocarbon (a-C:H), indicating that the nanocrystalline clusters were embedded in the DLC matrix. The crystallinity of TiN clusters, as well as the Ti atomic concentrations in the films, increased with an increase of substrate temperature. The substrate temperature applied to form a crystalline phase in the DLC matrix induced a graphitization of amorphous hydrocarbon matrix. The increase of volume fraction of TiN nanocrystalline clusters in the DLC matrix enhanced the mechanical properties of nanostructured coatings, although the graphite-like structural transition of DLC matrix happened due to the applied heating

  7. Increased charge storage capacity of titanium nitride electrodes by deposition of boron-doped nanocrystalline diamond films

    DEFF Research Database (Denmark)

    Meijs, Suzan; McDonald, Matthew; Sørensen, Søren

    2015-01-01

    The aim of this study was to investigate the feasibility of depositing a thin layer of boron-doped nanocrystalline diamond (B-NCD) on titanium nitride (TiN) coated electrodes and the effect this has on charge injection properties. The charge storage capacity increased by applying the B-NCD film...

  8. The Field Emission Characteristics of Titanium-Doped Nano-Diamonds

    Institute of Scientific and Technical Information of China (English)

    YANG Yan-Ning; ZHANG Zhi-Yong; ZHANG Fu-Chun; DONG Jun-Tang; ZHAO Wu; ZHAI Chun-Xue; ZHANG Wei-Hu

    2012-01-01

    An electrophoresis solution,prepared in a specific ratio of titanium (Ti)-doped nano-diamond,is dispersed by ultrasound and the nano-diamond coating is then deposited on a polished Ti substrate by electrophoresis.After high-temperature vacuum annealing,the appearance of the surface and the microstructures of the coating are observed by a metallomicroscope,scanning electron microscopy and Raman spectroscopy.The field emission characteristics and luminescence features are also tested,and the mechanism of the field emission characteristics of the Ti-doped nano-diamond is analyzed.The experimental results show that under the same conditions,the diamond-coated surface (by deposition) is more uniform after doping with 5 mg of Ti powder.Compared with the undoped nano-diamond cathode,the turn-on fields decline from 6.95 to 5.95 V/μm.When the electric field strength is 13.80 V/μm,the field emission current density increases to 130.00 μA/cm2.Under the applied fields,the emission current is stable and the luminescence is at its best,while the field emission characteristics of the 10 mg Ti-doped coating become worse,as does the luminescence.The reason for this could be that an excessive amount of TiC is generated on the surface of the coating.%An electrophoresis solution, prepared in a speciGc ratio of titanium (Ti)-doped nano-diamond, is dispersed by ultrasound and the nano-diamond coating is then deposited on a polished Ti substrate by electrophoresis. After high-temperature vacuum annealing, the appearance of the surface and the microstructures of the coating are observed by a metallomicroscope, scanning electron microscopy and Raman spectroscopy. The field emission characteristics and luminescence features are also tested, and the mechanism of the field emission characteristics of the Ti-doped nano-diamond is analyzed. The experimental results show that under the same conditions, the diamond-coated surface (by deposition) is more uniform after doping with 5 mg of Ti

  9. Development of a radio frequency atmospheric pressure plasma jet for diamond-like carbon coatings on stainless steel substrates

    Science.gov (United States)

    Sohbatzadeh, F.; Samadi, O.; Siadati, S. N.; Etaati, G. R.; Asadi, E.; Safari, R.

    2016-10-01

    In this paper, an atmospheric pressure plasma jet with capacitively coupled radio frequency discharge was developed for diamond-like carbon (DLC) coatings on stainless steel substrates. The plasma jet was generated by argon-methane mixture and its physical parameters were investigated. Relation between the plasma jet length and width of the powered electrode was discussed. Optical and electrical characteristics were studied by optical emission spectroscopy, voltage and current probes, respectively. The evolutions of various species like ArI, C2 and CH along the jet axis were investigated. Electron temperature and density were estimated by Boltzmann plot method and Saha-Boltzmann equation, respectively. Finally, a diamond-like carbon coating was deposited on stainless steel-304 substrates by the atmospheric pressure radio frequency plasma jet in ambient air. Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy and Vickers hardness test were used to study the deposited films. The length of the jet was increased by increasing the width of the powered electrode. The estimated electron temperature and density were 1.43 eV and 1.39 × 1015 cm-3, respectively. Averaged Vicker's hardness of the coated sample was three times greater than that of the substrate. The SEM images of the deposited thin films revealed a 4.5 μm DLC coated for 20 min.

  10. Silicon solar cell performance deposited by diamond like carbon thin film ;Atomic oxygen effects;

    Science.gov (United States)

    Aghaei, Abbas Ail; Eshaghi, Akbar; Karami, Esmaeil

    2017-09-01

    In this research, a diamond-like carbon thin film was deposited on p-type polycrystalline silicon solar cell via plasma-enhanced chemical vapor deposition method by using methane and hydrogen gases. The effect of atomic oxygen on the functioning of silicon coated DLC thin film and silicon was investigated. Raman spectroscopy, field emission scanning electron microscopy, atomic force microscopy and attenuated total reflection-Fourier transform infrared spectroscopy were used to characterize the structure and morphology of the DLC thin film. Photocurrent-voltage characteristics of the silicon solar cell were carried out using a solar simulator. The results showed that atomic oxygen exposure induced the including oxidation, structural changes, cross-linking reactions and bond breaking of the DLC film; thus reducing the optical properties. The photocurrent-voltage characteristics showed that although the properties of the fabricated thin film were decreased after being exposed to destructive rays, when compared with solar cell without any coating, it could protect it in atomic oxygen condition enhancing solar cell efficiency up to 12%. Thus, it can be said that diamond-like carbon thin layer protect the solar cell against atomic oxygen exposure.

  11. The bonding of protective films of amorphic diamond to titanium

    Science.gov (United States)

    Collins, C. B.; Davanloo, F.; Lee, T. J.; Jander, D. R.; You, J. H.; Park, H.; Pivin, J. C.

    1992-04-01

    Films of amorphic diamond can be deposited from laser plasma ions without the use of catalysts such as hydrogen or fluorine. Prepared without columnar patterns of growth, the layers of this material have been reported to have ``bulk'' values of mechanical properties that have suggested their usage as protective coatings for metals. Described here is a study of the bonding and properties realized in one such example, the deposition of amorphic diamond on titanium. Measurements with Rutherford backscattering spectrometry and transmission electron microscopy showed that the diamond coatings deposited from laser plasmas were chemically bonded to Ti substrates in 100-200-Å-thick interfacial layers containing some crystalline precipitates of TiC. Resistance to wear was estimated with a modified sand blaster and in all cases the coating was worn away without any rupture or deterioration of the bonding layer. Such wear was greatly reduced and lifetimes of the coated samples were increased by a factor of better than 300 with only 2.7 μm of amorphic diamond.

  12. Multilayer CVD Diamond Coatings in the Machining of an Al6061-15 Vol % Al2O3 Composite

    Directory of Open Access Journals (Sweden)

    Mohammadmehdi Shabani

    2017-10-01

    Full Text Available Ceramic cutting inserts coated with ten-fold alternating micro- and nanocrystalline diamond (MCD/NCD layers grown by hot filament chemical vapor deposition (CVD were tested in the machining of an Al based metallic matrix composite (MMC containing 15 vol % Al2O3 particles. Inserts with total coating thicknesses of approximately 12 µm and 24 µm were produced and used in turning: cutting speed (v of 250 to 1000 m·min−1; depth of cut (DOC from 0.5 to 3 mm and feed (f between 0.1 and 0.4 mm·rev−1. The main cutting force increases linearly with DOC (ca. 294 N per mm and with feed (ca. 640 N per mm·rev−1. The thicker coatings work within the following limits: DOC up to 1.5 mm and maximum speeds of 750 m·min−1 for feeds up to 0.4 mm·rev−1. Flank wear is predominant but crater wear is also observed due to the negative tool normal rake. Layer-by-layer wear of the tool rake, and not total delamination from the substrate, evidenced one of the advantages of using a multilayer design. The MCD/NCD multilayer diamond coated indexable inserts have longer tool life than most CVD diamond systems and behave as well as most polycrystalline diamond (PCD tools.

  13. Friction and wear performance of diamond-like carbon, boron carbide, and titanium carbide coatings against glass

    International Nuclear Information System (INIS)

    Daniels, B.K.; Brown, D.W.; Kimock, F.M.

    1997-01-01

    Protection of glass substrates by direct ion beam deposited diamond-like carbon (DLC) coatings was observed using a commercial pin-on-disk instrument at ambient conditions without lubrication. Ion beam sputter-deposited titanium carbide and boron carbide coatings reduced sliding friction, and provided tribological protection of silicon substrates, but the improvement factor was less than that found for DLC. Observations of unlubricated sliding of hemispherical glass pins at ambient conditions on uncoated glass and silicon substrates, and ion beam deposited coatings showed decreased wear in the order: uncoated glass>uncoated silicon>boron carbide>titanium carbide>DLC>uncoated sapphire. Failure mechanisms varied widely and are discussed. Generally, the amount of wear decreased as the sliding friction decreased, with the exception of uncoated sapphire substrates, for which the wear was low despite very high friction. There is clear evidence that DLC coatings continue to protect the underlying substrate long after the damage first penetrates through the coating. The test results correlate with field use data on commercial products which have shown that the DLC coatings provide substantial extension of the useful lifetime of glass and other substrates. copyright 1997 Materials Research Society

  14. Effects of a diamond-like carbon coating on the frictional properties of orthodontic wires.

    Science.gov (United States)

    Muguruma, Takeshi; Iijima, Masahiro; Brantley, William A; Mizoguchi, Itaru

    2011-01-01

    To test the hypothesis that a diamond-like carbon coating does not affect the frictional properties of orthodontic wires. Two types of wires (nickel-titanium and stainless steel) were used, and diamond-like carbon (DLC) films were deposited on the wires. Three types of brackets, a conventional stainless steel bracket and two self-ligating brackets, were used for measuring static friction. DLC layers were observed by three-dimensional scanning electron microscopy (3D-SEM), and the surface roughness was measured. Hardness and elastic modulus were obtained by nanoindentation testing. Frictional forces and surface roughness were compared by the Kruskal-Wallis and Mann-Whitney U-tests. The hardness and elastic modulus of the wires were compared using Student's t-test. When angulation was increased, the DLC-coated wires showed significantly less frictional force than the as-received wires, except for some wire/bracket combinations. Thin DLC layers were observed on the wire surfaces by SEM. As-received and DLC-coated wires had similar surface morphologies, and the DLC-coating process did not affect the surface roughness. The hardness of the surface layer of the DLC-coated wires was much higher than for the as-received wires. The elastic modulus of the surface layer of the DLC-coated stainless steel wire was less than that of the as-received stainless steel wire, whereas similar values were found for the nickel-titanium wires. The hypothesis is rejected. A DLC-coating process does reduce the frictional force.

  15. Chemical vapor deposition of nanocrystalline diamond films

    International Nuclear Information System (INIS)

    Vyrovets, I.I.; Gritsyna, V.I.; Dudnik, S.F.; Opalev, O.A.; Reshetnyak, O.M.; Strel'nitskij, V.E.

    2008-01-01

    The brief review of the literature is devoted to synthesis of nanocrystalline diamond films. It is shown that the CVD method is an effective way for deposition of such nanostructures. The basic technological methods that allow limit the size of growing diamond crystallites in the film are studied.

  16. Carbon diffusion in uncoated and titanium nitride coated iron substrates during microwave plasma assisted chemical vapor deposition of diamond

    International Nuclear Information System (INIS)

    Weiser, P.S.; Prawer, S.; Manory, R.R.; Paterson, P.J.K.; Stuart, Sue-Anne

    1992-01-01

    Auger Electron Spectroscopy has been employed to investigate the effectiveness of thin films of TiN as barriers to carbon diffusion during Chemical Vapor Deposition (CVD) of diamond onto Fe substrates. Auger Depth Profiling was used to monitor the C concentration in the TiN layer, through the interface and into the substrate both before and after CVD diamond deposition. The results show that a layer of TiN only 250 Angstroems thick is sufficient to inhibit soot formation on the Fe surface and C diffusion into the Fe bulk. 14 refs., 4 figs

  17. Cutting force and wear evaluation in peripheral milling by CVD diamond dental tools

    International Nuclear Information System (INIS)

    Polini, R.; Allegri, A.; Guarino, S.; Quadrini, F.; Sein, H.; Ahmed, W.

    2004-01-01

    Co-cemented tungsten carbide (WC-Co) tools are currently employed in dental application for prosthesis fabrication. The deposition of a diamond coating onto WC-Co tools could allow both to increase the tool life and tool performance at higher speeds. However, at present it is very difficult to quantify the effective advantage of the application of a diamond coating onto dental tools compared to traditional uncoated tools. Therefore, in this work, we have deposited diamond coatings onto WC-Co dental tools having different geometries by Hot Filament Chemical Vapour Deposition (HFCVD). Prior to deposition, the WC-Co tools were pre-treated in order to roughen the surface and to modify the chemical surface composition. The use of the HFCVD process enabled the deposition of a uniform coating despite the complex geometries of the dental mills. For the first time, in accordance to the knowledge of the authors, we have studied and compared the cutting behaviour of both virgin and diamond-coated dental tools by measuring both wear and cutting force time evolution under milling a very hard Co-Cr-Mo dental alloy. To ensure constant cutting rate (20,000-r.p.m. cutting rate, 0.01-m/min feed rate and 0.5-mm depth of cut), a proper experimental apparatus was used. Three different mill geometries were considered in both coated and uncoated conditions. The results showed that, under the high-speed conditions employed, uncoated tools underwent to catastrophic failure within a few seconds of machining. Diamond-coated tools exhibited much longer tool lives. Lower forces were measured when the coated tool was employed due to the much lower material-mill friction. The best behaviour was observed for coated mills with the presence of a chip-breaker

  18. Application of Chlorine-Assisted Chemical Vapor Deposition of Diamond at Low Temperatures

    Science.gov (United States)

    Pan, Chenyu; Altemir, David A.; Margrave, John L.; Hauge, Robert H.

    1994-01-01

    Low temperature deposition of diamond has been achieved by a chlorine-assisted diamond chemical vapor deposition (CA-CVD) process. This method begins with the thermal dissociation of molecular chlorine into atomic chlorine in a resistively heated graphite furnace at temperatures between 1300 and 1500 deg. C. The atomic chlorine, upon mixing, subsequently reacts with molecular hydrogen and hydrocarbons. The rapid exchange reactions between the atomic chlorine, molecular hydrogen, and hydrocarbons give rise to the atomic hydrogen and carbon precursors required for diamond deposition. Homoepitaxial diamond growth on diamond substrates has been studied over the substrate temperature range of 100-950 C. It was found that the diamond growth rates are approximately 0.2 microns/hr in the temperature range between 102 and 300 C and that the growth rates do not decrease significantly with a decrease in substrate temperature. This is unique because the traditional diamond deposition using H2/CH4 systems usually disappears at substrate temperatures below approx. 500 deg. C. This opens up a possible route to the deposition of diamond on low-melting point materials such as aluminum and its alloys.

  19. One step deposition of highly adhesive diamond films on cemented carbide substrates via diamond/β-SiC composite interlayers

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Tao; Zhuang, Hao; Jiang, Xin, E-mail: xin.jiang@uni-siegen.de

    2015-12-30

    Graphical abstract: - Highlights: • Novel diamond/beta-silicon carbide composite gradient interlayers were synthesized. • The interlayer features a cross-sectional gradient with increasing diamond content. • Diamond top layers and the interlayers were deposited in one single process. • The adhesion of the diamond film is drastically improved by employing the interlayer. • The stress was suppressed by manipulating the distribution of diamond and silicon carbide. - Abstract: Deposition of adherent diamond films on cobalt-cemented tungsten carbide substrates has been realized by application of diamond/beta-silicon carbide composite interlayers. Diamond top layers and the interlayers were deposited in one single process by hot filament chemical vapor deposition technique. Two different kinds of interlayers have been employed, namely, gradient interlayer and interlayer with constant composition. The distribution of diamond and beta-silicon carbide phases was precisely controlled by manipulating the gas phase composition. X-ray diffraction and Raman spectroscopy were employed to determine the existence of diamond, beta-silicon carbide and cobalt silicides (Co{sub 2}Si, CoSi) phases, as well as the quality of diamond crystal and the residual stress in the films. Rockwell-C indentation tests were carried out to evaluate the film adhesion. It is revealed that the adhesion of the diamond film is drastically improved by employing the interlayer. This is mainly influenced by the residual stress in the diamond top layer, which is induced by the different thermal expansion coefficient of the film and the substrate. It is even possible to further suppress the stress by manipulating the distribution of diamond and beta-silicon carbide in the interlayer. The most adhesive diamond film on cemented carbide is thus obtained by employing a gradient composite interlayer.

  20. Understanding the chemical vapor deposition of diamond: recent progress

    International Nuclear Information System (INIS)

    Butler, J E; Mankelevich, Y A; Cheesman, A; Ma, Jie; Ashfold, M N R

    2009-01-01

    In this paper we review and provide an overview to the understanding of the chemical vapor deposition (CVD) of diamond materials with a particular focus on the commonly used microwave plasma-activated chemical vapor deposition (MPCVD). The major topics covered are experimental measurements in situ to diamond CVD reactors, and MPCVD in particular, coupled with models of the gas phase chemical and plasma kinetics to provide insight into the distribution of critical chemical species throughout the reactor, followed by a discussion of the surface chemical process involved in diamond growth.

  1. Flexible diamond-like carbon film coated on rubber

    NARCIS (Netherlands)

    Pei, Y.T.; Bui, X.L.; Pal, J.P. van der; Martinez-Martinez, D.; Hosson, J.Th.M. De

    2013-01-01

    Dynamic rubber seals are major sources of friction of lubrication systems and bearings, which may take up to 70% of the total friction. The solution we present is to coat rubbers with diamond-like carbon (DLC) thin films by which the coefficient of friction is reduced to less than one tenth. Coating

  2. Diamond deposition using a planar radio frequency inductively coupled plasma

    Science.gov (United States)

    Bozeman, S. P.; Tucker, D. A.; Stoner, B. R.; Glass, J. T.; Hooke, W. M.

    1995-06-01

    A planar radio frequency inductively coupled plasma has been used to deposit diamond onto scratched silicon. This plasma source has been developed recently for use in large area semiconductor processing and holds promise as a method for scale up of diamond growth reactors. Deposition occurs in an annulus which coincides with the area of most intense optical emission from the plasma. Well-faceted diamond particles are produced when the substrate is immersed in the plasma.

  3. Gas barrier properties of diamond-like carbon films coated on PTFE

    International Nuclear Information System (INIS)

    Ozeki, K.; Nagashima, I.; Ohgoe, Y.; Hirakuri, K.K.; Mukaibayashi, H.; Masuzawa, T.

    2009-01-01

    Diamond-like carbon (DLC) films were deposited on polytetrafluoroethylene (PTFE) using radio frequency (RF) plasma-enhanced chemical vapour deposition (PE-CVD). Before the DLC coating, the PTFE substrate was modified with a N 2 plasma pre-treatment to enhance the adhesive strength of the DLC to the substrate. The influences of the N 2 plasma pre-treatment and process pressure on the gas permeation properties of these DLC-coated PTFE samples were investigated. In the Raman spectra, the G peak position shifted to a lower wave number with increasing process pressure. With scanning electron microscopy (SEM), a network of microcracks was observed on the surface of the DLC film without N 2 plasma pre-treatment. The density of these cracks decreased with increasing process pressure. In the film subjected to a N 2 plasma pre-treatment, no cracks were observed at any process pressure. In the gas barrier test, the gas permeation decreased drastically with increasing film thickness and saturated at a thickness of 0.2 μm. The DLC-coated PTFE with the N 2 plasma pre-treatment exhibited a greater reduction in gas permeation than did the samples without pre-treatment. For both sample types, gas permeation decreased with increasing process pressure.

  4. On the development of a dual-layered diamond-coated tool for the effective machining of titanium Ti-6Al-4V alloy

    International Nuclear Information System (INIS)

    Srinivasan, Balaji; Rao, Balkrishna C; Ramachandra Rao, M S

    2017-01-01

    This work is focused on the development of a dual-layered diamond-coated tungsten carbide tool for machining titanium Ti-6Al-4V alloy. A hot-filament chemical vapor deposition technique was used to synthesize diamond films on tungsten carbide tools. A boron-doped diamond interlayer was added to a microcrystalline diamond layer in an attempt to improve the interface adhesion strength. The dual-layered diamond-coated tool was employed in machining at cutting speeds in the range of 70 to 150 m min −1 with a lower feed and a lower depth of cut of 0.5 mm rev −1 and 0.5 mm, respectively, to operate in the transition from adhesion- to diffusion-tool-wear and thereby arrive at suitable conditions for enhancing tool life. The proposed tool was then compared, on the basis of performance under real-time cutting conditions, with commercially available microcrystalline diamond, nanocrystalline diamond, titanium nitride and uncoated tungsten carbide tools. The life and surface finish of the proposed dual-layered tool and uncoated tungsten carbide were also investigated in interrupted cutting such as milling. The results of this study show a significant improvement in tool life and finish of Ti-6Al-4V parts machined with the dual-layered diamond-coated tool when compared with its uncoated counterpart. These results pave the way for the use of a low-cost tool, with respect to, polycrystalline diamond for enhancing both tool life and machining productivity in critical sectors fabricating parts out of titanium Ti-6Al-4V alloy. The application of this coating technology can also be extended to the machining of non-ferrous alloys owing to its better adhesion strength. (paper)

  5. Diamond coating in accelerator structure

    International Nuclear Information System (INIS)

    Lin, X.E.

    1998-08-01

    The future accelerators with 1 GeV/m gradient will give rise to hundreds of degrees instantaneous temperature rise on the copper surface. Due to its extraordinary thermal and electric properties, diamond coating on the surface is suggested to remedy this problem. Multi-layer structure, with the promise of even more temperature reduction, is also discussed, and a proof of principle experiment is being carried out

  6. Diamond-Like Carbon Coatings as Encapsulants for Photovoltaic Solar Cells

    International Nuclear Information System (INIS)

    Pern, F. J.; Panosyan, Zh.; Gippius, A. A.; Kontsevoy, J. A.; Touryan, K.; Voskanyan, S.; Yengibaryan, Y.

    2005-01-01

    High-quality single-layer and bilayer diamond-like carbon (DLC) thin films are fabricated by two technologies, namely, ion-assisted plasma-enhanced deposition (IAPED) and electron cyclotron resonance (ECR) deposition. Deposition on various substrates, such as sapphires and solar cells, has been performed at low substrate temperatures (50 ∼ 80 C). The two deposition technologies allow good control over the growth conditions to produce DLC films with desired optical properties, thickness, and energy bandgap. The bilayer-structured DLC can be fabricated by using IAPED for the bottom layer followed by ECR for the top layer, or just by IAPED for both layers with different compositions. The DLC films have shown good spatial uniformity, density, microhardness, and adhesion strength. They exhibit excellent stability against attack by strong acids, prolonged damp-heat exposure at 85 C and 85% relative humidity, mechanical scratch, ultrasonication, and irradiation by ultraviolet (UV), protons, and electrons. When deposited on crystalline Si and GaAs solar cells in single-layer and/or bilayer structure, the DLC films not only serve as antireflection coating and protective encapsulant, but also improve the cell efficiencies

  7. The Barrier Properties of PET Coated DLC Film Deposited by Microwave Surface-Wave PECVD

    Science.gov (United States)

    Yin, Lianhua; Chen, Qiang

    2017-12-01

    In this paper we report the investigation of diamond-like carbon (DLC) deposited by microwave surface-wave plasma enhanced chemical vapor deposition (PECVD) on the polyethylene terephthalate (PET) web for the purpose of the barrier property improvement. In order to characterize the properties of DLC coatings, we used several substrates, silicon wafer, glass, and PET web and KBr tablet. The deposition rate was obtained by surface profiler based on the DLC deposited on glass substrates; Fourier transform infrared spectroscope (FTIR) was carried out on KBr tablets to investigate chemical composition and bonding structure; the morphology of the DLC coating was analyzed by atomic force microscope (AFM) on Si substrates. For the barrier properties of PET webs, we measured the oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) after coated with DLC films. We addressed the film barrier property related to process parameters, such as microwave power and pulse parameter in this work. The results show that the DLC coatings can greatly improve the barrier properties of PET webs.

  8. Ti-doped hydrogenated diamond like carbon coating deposited by hybrid physical vapor deposition and plasma enhanced chemical vapor deposition

    Science.gov (United States)

    Lee, Na Rae; Sle Jun, Yee; Moon, Kyoung Il; Sunyong Lee, Caroline

    2017-03-01

    Diamond-like carbon films containing titanium and hydrogen (Ti-doped DLC:H) were synthesized using a hybrid technique based on physical vapor deposition (PVD) and plasma enhanced chemical vapor deposition (PECVD). The film was deposited under a mixture of argon (Ar) and acetylene gas (C2H2). The amount of Ti in the Ti-doped DLC:H film was controlled by varying the DC power of the Ti sputtering target ranging from 0 to 240 W. The composition, microstructure, mechanical and chemical properties of Ti-doped DLC:H films with varying Ti concentrations, were investigated using Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), nano indentation, a ball-on-disk tribometer, a four-point probe system and dynamic anodic testing. As a result, the optimum composition of Ti in Ti-doped DLC:H film using our hybrid method was found to be a Ti content of 18 at. %, having superior electrical conductivity and high corrosion resistance, suitable for bipolar plates. Its hardness value was measured to be 25.6 GPa with a low friction factor.

  9. Reduction in static friction by deposition of a homogeneous diamond-like carbon (DLC) coating on orthodontic brackets.

    Science.gov (United States)

    Akaike, Shun; Hayakawa, Tohru; Kobayashi, Daishiro; Aono, Yuko; Hirata, Atsushi; Hiratsuka, Masanori; Nakamura, Yoshiki

    2015-01-01

    In orthodontics, a reduction in static friction between the brackets and wire is important to enable easy tooth movement. The aim of this study was to examine the effects of a homogeneous diamond-like carbon (DLC) coating on the whole surfaces of slots in stainless steel orthodontic brackets on reducing the static friction between the brackets and the wire. The DLC coating was characterized using Raman spectroscopy, surface roughness and contact angle measurements, and SEM observations. Rectangular stainless steel and titanium-molybdenum alloy wires with two different sizes were employed, and the static friction between the brackets and wire was measured under dry and wet conditions. The DLC coating had a thickness of approximately 1.0 μm and an amorphous structure was identified. The results indicated that the DLC coating always led to a reduction in static friction.

  10. Electron field emission for ultrananocrystalline diamond films

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, A. R.; Auciello, O.; Ding, M. Q.; Gruen, D. M.; Huang, Y.; Zhirnov, V. V.; Givargizov, E. I.; Breskin, A.; Chechen, R.; Shefer, E. (and others)

    2001-03-01

    Ultrananocrystalline diamond (UNCD) films 0.1--2.4 {mu}m thick were conformally deposited on sharp single Si microtip emitters, using microwave CH{sub 4}--Ar plasma-enhanced chemical vapor deposition in combination with a dielectrophoretic seeding process. Field-emission studies exhibited stable, extremely high (60--100 {mu}A/tip) emission current, with little variation in threshold fields as a function of film thickness or Si tip radius. The electron emission properties of high aspect ratio Si microtips, coated with diamond using the hot filament chemical vapor deposition (HFCVD) process were found to be very different from those of the UNCD-coated tips. For the HFCVD process, there is a strong dependence of the emission threshold on both the diamond coating thickness and Si tip radius. Quantum photoyield measurements of the UNCD films revealed that these films have an enhanced density of states within the bulk diamond band gap that is correlated with a reduction in the threshold field for electron emission. In addition, scanning tunneling microscopy studies indicate that the emission sites from UNCD films are related to minima or inflection points in the surface topography, and not to surface asperities. These data, in conjunction with tight binding pseudopotential calculations, indicate that grain boundaries play a critical role in the electron emission properties of UNCD films, such that these boundaries: (a) provide a conducting path from the substrate to the diamond--vacuum interface, (b) produce a geometric enhancement in the local electric field via internal structures, rather than surface topography, and (c) produce an enhancement in the local density of states within the bulk diamond band gap.

  11. 钛沉积工艺制备TiN/cBN和TiC/金钢石涂层颗粒%Fabrication of TiN/cBN and TiC/diamond coated particles by titanium deposition process

    Institute of Scientific and Technical Information of China (English)

    Walid M. DAOUSH; Hee S. PARK; Soon H. HONG

    2014-01-01

    Cubic boron nitride particles coated by titanium nitride (TiN/cBN) as well as diamond particles coated by titanium carbide (TiC/diamond) were prepared by Ti molten salt deposition followed by heat-treatment process. cBN or diamond particles were mixed separately with Ti powders and molten salts (KCl, NaCl and K2TiF6). The mixture was heated at 900 °C under argon atmosphere. The produced particles were heat-treated under hydrogen at 1000 °C. The morphologies and chemical compositions of the produced particles were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and focused ion beam (FIB). The results show that the cBN and the diamond particles are coated by nano-sized Ti layers. By heat-treatment of the Ti/cBN and TiC/diamond coated particles under hydrogen atmosphere, the deposited Ti layers were interacted by the in-situ transformation reaction with the surfaces of cBN and diamond particles and converted to titanium compounds (TiN and TiC), respectively.%用钛熔盐沉积及热处理工艺分别制备碳化钛涂覆的立方碳化硼颗粒(TiN/cBN)及碳化钛涂覆的金刚石颗粒(TiC/金刚石)。将cBN或金刚石颗粒分别与钛粉和KCl、NaCl和K2TiF6熔盐混合。将所得混合物在Ar气氛中加热至900°C,然后在H2气氛中于1000°C进行热处理。采用扫描电镜、X射线衍射和聚焦离子束技术对所制得颗粒进行表征。结果表明:cBN和金刚石颗粒表面已覆盖了纳米钛层。对Ti/cBN和TiC/金刚石涂层颗粒进行热处理后,颗粒表面沉积的Ti层与cBN和金刚石颗粒发生了原位化学反应,分别转化为钛化合物TiN和TiC。

  12. Low-emissivity coating of amorphous diamond-like carbon/Ag-alloy multilayer on glass

    International Nuclear Information System (INIS)

    Chiba, Kiyoshi; Takahashi, Toshiyuki; Kageyama, Takashi; Oda, Hironori

    2005-01-01

    Transparent low-emissivity (low-e) coatings comprising dielectrics of amorphous diamond-like carbon (DLC) and Ag-alloy films are investigated. All films have been prepared by dc magnetron sputtering. An index of refraction of the DLC film deposited in a gas mixture of Ar/H 2 (4%) shows n = 1.80 + 0.047i at 500 nm wavelength. A multilayer stack of DLC (70 nm thick)/Ag 87.5 Cu 12.5 -alloy (10 nm)/DLC (140 nm)/Ag 87.5 Cu 12.5 -alloy (10 nm)/DLC (70 nm) has revealed clear interference spectra with spectra selectivity. This coating performs low emittance less than 0.1 for black body radiation at 297 K, exhibiting a transparent heat mirror property embedded in DLC films

  13. Optical and electrical properties of boron doped diamond thin conductive films deposited on fused silica glass substrates

    Energy Technology Data Exchange (ETDEWEB)

    Ficek, M.; Sobaszek, M.; Gnyba, M. [Department of Metrology and Optoelectronics, Gdansk University of Technology, 11/12G. Narutowicza St., 80-233 Gdansk (Poland); Ryl, J. [Department of Electrochemistry, Corrosion and Material Engineering, Gdansk University of Technology, 11/12 Narutowicza St., 80-233 Gdansk (Poland); Gołuński, Ł. [Department of Metrology and Optoelectronics, Gdansk University of Technology, 11/12G. Narutowicza St., 80-233 Gdansk (Poland); Smietana, M.; Jasiński, J. [Institute of Microelectronics and Optoelectronics, Warsaw University of Technology, 75 Koszykowa St., 00-662 Warsaw (Poland); Caban, P. [Institute of Electronic Materials Technology, 133 Wolczynska St., 01-919 Warsaw (Poland); Bogdanowicz, R., E-mail: rbogdan@eti.pg.gda.pl [Department of Metrology and Optoelectronics, Gdansk University of Technology, 11/12G. Narutowicza St., 80-233 Gdansk (Poland); Materials and Process Simulation Center, California Institute of Technology, Pasadena, CA 91125 (United States)

    2016-11-30

    Highlights: • Growth of 60% of transmittance diamond films with resistivity as low as 48 Ω cm. • Two step seeding process of fused silica: plasma hydrogenation and wet seeding. • Nanodiamond seeding density of 2 × 10{sup 10} cm{sup −2} at fused silica substrates. • High refractive index (2.4 @550 nm) was achieved for BDD films deposited at 500 °C. - Abstract: This paper presents boron-doped diamond (BDD) film as a conductive coating for optical and electronic purposes. Seeding and growth processes of thin diamond films on fused silica have been investigated. Growth processes of thin diamond films on fused silica were investigated at various boron doping level and methane admixture. Two step pre-treatment procedure of fused silica substrate was applied to achieve high seeding density. First, the substrates undergo the hydrogen plasma treatment then spin-coating seeding using a dispersion consisting of detonation nanodiamond in dimethyl sulfoxide with polyvinyl alcohol was applied. Such an approach results in seeding density of 2 × 10{sup 10} cm{sup −2}. The scanning electron microscopy images showed homogenous, continuous and polycrystalline surface morphology with minimal grain size of 200 nm for highly boron doped films. The sp{sup 3}/sp{sup 2} ratio was calculated using Raman spectra deconvolution method. A high refractive index (range of 2.0–2.4 @550 nm) was achieved for BDD films deposited at 500 °C. The values of extinction coefficient were below 0.1 at λ = 550 nm, indicating low absorption of the film. The fabricated BDD thin films displayed resistivity below 48 Ohm cm and transmittance over 60% in the visible wavelength range.

  14. Modelling of diamond deposition microwave cavity generated plasmas

    International Nuclear Information System (INIS)

    Hassouni, K; Silva, F; Gicquel, A

    2010-01-01

    Some aspects of the numerical modelling of diamond deposition plasmas generated using microwave cavity systems are discussed. The paper mainly focuses on those models that allow (i) designing microwave cavities in order to optimize the power deposition in the discharge and (ii) estimating the detailed plasma composition in the vicinity of the substrate surface. The development of hydrogen plasma models that may be used for the self-consistent simulation of microwave cavity discharge is first discussed. The use of these models for determining the plasma configuration, composition and temperature is illustrated. Examples showing how to use these models in order to optimize the cavity structure and to obtain stable process operations are also given. A transport model for the highly reactive H 2 /CH 4 moderate pressure discharges is then presented. This model makes possible the determination of the time variation of plasma composition and temperature on a one-dimensional domain located on the plasma axis. The use of this model to analyse the transport phenomena and the chemical process in diamond deposition plasmas is illustrated. The model is also utilized to analyse pulsed mode discharges and the benefit they can bring as far as diamond growth rate and quality enhancement are concerned. We, in particular, show how the model can be employed to optimize the pulse waveform in order to improve the deposition process. Illustrations on how the model can give estimates of the species density at the growing substrate surface over a wide domain of deposition conditions are also given. This brings us to discuss the implication of the model prediction in terms of diamond growth rate and quality. (topical review)

  15. Cathodoluminescence characteristics of polycrystalline diamond films grown by cyclic deposition method

    International Nuclear Information System (INIS)

    Seo, Soo-Hyung; Park, Chang-Kyun; Park, Jin-Seok

    2002-01-01

    Polycrystalline diamond films were deposited using a cyclic deposition method where the H 2 plasma for etching (t E ) and the CH 4 +H 2 plasma for growing (t G ) are alternately modulated with various modulation ratios (t E /t G ). From the measurement of full width at half maximum and I D /I G intensity ratio obtained from the Raman spectra, it was found that diamond defects and non-diamond carbon phases were reduced a little by adopting the cyclic deposition method. From the cathodoluminescence (CL) characteristics measured for deposited films, the nitrogen-related band (centered at approximately 590 nm) as well as the so-called band-A (centered at approximately 430 nm) were observed. As the cyclic ratio t E /t G increased, the relative intensity ratio of band-A to nitrogen-related band (I A /I N ) was found to monotonically decrease. In addition, analysis of X-ray diffraction spectra and scanning electron microscope morphologies showed that CL characteristics of deposited diamond films were closely related to their crystal orientations and morphologies

  16. CN distribution in flame deposition of diamond and its relation to the growth rate, morphology, and nitrogen incorporation of the diamond layer

    NARCIS (Netherlands)

    Klein-Douwel, R.J.H.; Schermer, J.J.; Meulen, ter J.J.

    1998-01-01

    Two-dimensional laser-induced fluorescence (2D-LIF) measurements areapplied to the chemical vapour deposition (CVD) of diamond by anoxyacetylene flame to visualize the distribution of CN in the gas phaseduring the diamond growth process. The obtained diamond deposits arecharacterized by optical as

  17. Sealing of hard CrN and DLC coatings with atomic layer deposition.

    Science.gov (United States)

    Härkönen, Emma; Kolev, Ivan; Díaz, Belén; Swiatowska, Jolanta; Maurice, Vincent; Seyeux, Antoine; Marcus, Philippe; Fenker, Martin; Toth, Lajos; Radnoczi, György; Vehkamäki, Marko; Ritala, Mikko

    2014-02-12

    Atomic layer deposition (ALD) is a thin film deposition technique that is based on alternating and saturating surface reactions of two or more gaseous precursors. The excellent conformality of ALD thin films can be exploited for sealing defects in coatings made by other techniques. Here the corrosion protection properties of hard CrN and diamond-like carbon (DLC) coatings on low alloy steel were improved by ALD sealing with 50 nm thick layers consisting of Al2O3 and Ta2O5 nanolaminates or mixtures. In cross sectional images the ALD layers were found to follow the surface morphology of the CrN coatings uniformly. Furthermore, ALD growth into the pinholes of the CrN coating was verified. In electrochemical measurements the ALD sealing was found to decrease the current density of the CrN coated steel by over 2 orders of magnitude. The neutral salt spray (NSS) durability was also improved: on the best samples the appearance of corrosion spots was delayed from 2 to 168 h. On DLC coatings the adhesion of the ALD sealing layers was weaker, but still clear improvement in NSS durability was achieved indicating sealing of the pinholes.

  18. Nucleation of microwave plasma CVD diamond on molybdenum (Mo) substrate

    International Nuclear Information System (INIS)

    Inderjeet, K.; Ramesh, S.

    2000-01-01

    Molybdenum is a metal, which is gaining increasing significance in industrial applications. The main use of Mo is as all alloying element added in small amounts to steel, irons and non- ferrous alloys in order to enhance the strength, toughness and wear resistance. Mo is also vastly being employed in the automotive and aircraft industries, mainly due to its low coefficient of friction. Diamond, on be other hand, is a unique material for innumerable applications because of its usual combination of physical and chemical properties. Several potential applications can be anticipated for diamond in many sectors including electronics, optics, as protective corrosion resistant coatings, cutting tools, etc. With the enhancement in science and technology, diamond microcrystals and thin films are now being produced from the vapour phase by a variety of chemical vapour deposition (CVD) techniques; such as microwave plasma CVD. With such technology being made available, it is envisage that diamond-coated molybdenum would further enhance the performance and to open up new avenue for Mo in various industries. Therefore, it is the aim of the present work to study the nucleation and growth of diamond particles on Mo surface by employing microwave plasma CVD (MAPCVD). In the present work, diamond deposition was carried out in several stages by varying the deposition distance. The nucleation and growth rate were studied using scanning electron microscopy (SEM). In addition, the existence of diamond was verified by X-ray diffraction (XRD) analysis. It has been found that the nucleation and growth rate of diamond particles were influenced by the deposition height between the substrate and plasma. Under the optimum condition, well defined diamond crystallites distributed homogeneously throughout the surface, could be obtained. Some of the important parameters controlling the deposition and growth of diamond particles on Mo surface are discussed. (author)

  19. Cavitation erosion resistance of diamond-like carbon coating on stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Feng; Jiang, Shuyun, E-mail: jiangshy@seu.edu.cn

    2014-02-15

    Two diamond-like carbon (DLC) coatings are prepared on stainless steel 304 by cathodic arc plasma deposition technology at different substrate bias voltages and arc currents (−200 V/80 A, labeled DLC-1, and −100 V/60 A, labeled DLC-2). Cavitation tests are performed by using a rotating-disk test rig to explore the cavitation erosion resistance of the DLC coating. The mass losses, surface morphologies, chemical compositions and the phase constituents of the specimens after cavitation tests are examined by using digital balance, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), respectively. The results indicate that the DLC-2 coatings can elongate the incubation period of stainless steel, leading to an excellent cavitation erosion resistance as compared to the untreated stainless steel specimens. After duration of 100 h cavitation test, serious damaged surfaces and plenty of scratches can be observed on the surfaces of the stainless steel specimens, while only a few grooves and tiny pits are observed on the DLC-2 coatings. It is concluded that, decreasing micro defects and increasing adhesion can reduce the delamination of DLC coating, and the erosion continues in the stainless steel substrate after DLC coating failure, and the eroded surface of the substrate is subjected to the combined action from cavitation erosion and slurry erosion.

  20. The Effect of Bias Voltage and Gas Pressure on the Structure, Adhesion and Wear Behavior of Diamond Like Carbon (DLC Coatings With Si Interlayers

    Directory of Open Access Journals (Sweden)

    Liam Ward

    2014-04-01

    Full Text Available In this study diamond like carbon (DLC coatings with Si interlayers were deposited on 316L stainless steel with varying gas pressure and substrate bias voltage using plasma enhanced chemical vapor deposition (PECVD technology. Coating and interlayer thickness values were determined using X-ray photoelectron spectroscopy (XPS which also revealed the presence of a gradient layer at the coating substrate interface. Coatings were evaluated in terms of the hardness, elastic modulus, wear behavior and adhesion. Deposition rate generally increased with increasing bias voltage and increasing gas pressure. At low working gas pressures, hardness and modulus of elasticity increased with increasing bias voltage. Reduced hardness and modulus of elasticity were observed at higher gas pressures. Increased adhesion was generally observed at lower bias voltages and higher gas pressures. All DLC coatings significantly improved the overall wear resistance of the base material. Lower wear rates were observed for coatings deposited with lower bias voltages. For coatings that showed wear tracks considerably deeper than the coating thickness but without spallation, the wear behavior was largely attributed to deformation of both the coating and substrate with some cracks at the wear track edges. This suggests that coatings deposited under certain conditions can exhibit ultra high flexible properties.

  1. Deposition of DLC Film on Stainless Steel Substrates Coated by Nickel Using PECVD Method.

    Science.gov (United States)

    Khalaj, Zahra; Ghoranneviss, Mahmood; Vaghri, Elnaz; Saghaleini, Amir; Diudea, Mircea V

    2012-06-01

    Research on diamond-like carbon (DLC) films has been devoted to find both optimized conditions and characteristics of the deposited films on various substrates. In the present work, we investigate the quality of the DLC films grown on stainless steel substrates using different thickness of the nickel nanoparticle layers on the surface. Nickel nanoparticles were sputtered on the stainless steel substrates at 200 °C by a DC-sputtering system to make a good adherence between DLC coating and steel substrates. Atomic Force Microscopy was used to characterize the surface roughness and distribution function of the nickel nanoparticles on the substrate surface. Diamond like carbon films were deposited on stainless steel substrates coated by nickel using pure acetylene and C2H2/H2 with 15% flow ratio by DC-Plasma Enhanced Chemical Vapor Deposition (PECVD) systems. Microstructural analysis by Raman spectroscopy showed a low intensity ratio ID/IG for DLC films by increasing the Ni layer thickness on the stainless steel substrates. Fourier Transforms Infrared spectroscopy (FTIR) evidenced the peaks attributed to C-H bending and stretching vibration modes in the range of 1300-1700 cm-1 and 2700-3100 cm-1, respectively, in good agreement with the Raman spectroscopy and confirmed the DLC growth in all samples.

  2. Effect of TiO2/Al2O3 film coated diamond abrasive particles by sol-gel technique

    Science.gov (United States)

    Hu, Weida; Wan, Long; Liu, Xiaopan; Li, Qiang; Wang, Zhiqi

    2011-04-01

    The diamond abrasive particles were coated with the TiO2/Al2O3 film by the sol-gel technique. Compared with the uncoated diamonds, the TiO2/Al2O3 film was excellent material for the protection of the diamonds. The results showed that the incipient oxidation temperature of the TiO2/Al2O3 film coated diamonds in air atmosphere was 775 °C, which was higher 175 °C than that of the uncoated diamonds. And the coated diamonds also had better the diamond's single particle compressive strength and the impact toughness than that of uncoated diamonds after sintering at 750 °C. For the vitrified bond grinding wheels, replacing the uncoated diamonds with the TiO2/Al2O3 film coated diamonds, the volume expansion of the grinding wheels decreased from 6.2% to 3.4%, the porosity decreased from 35.7% to 25.7%, the hardness increased from 61.2HRC to 66.5HRC and the grinding ratio of the vitrified bond grinding wheels to carbide alloy (YG8) increased from 11.5 to 19.1.

  3. Coating NiTi archwires with diamond-like carbon films: reducing fluoride-induced corrosion and improving frictional properties.

    Science.gov (United States)

    Huang, S Y; Huang, J J; Kang, T; Diao, D F; Duan, Y Z

    2013-10-01

    This study aims to coat diamond-like carbon (DLC) films onto nickel-titanium (NiTi) orthodontic archwires. The film protects against fluoride-induced corrosion and will improve orthodontic friction. 'Mirror-confinement-type electron cyclotron resonance plasma sputtering' was utilized to deposit DLC films onto NiTi archwires. The influence of a fluoride-containing environment on the surface topography and the friction force between the brackets and archwires were investigated. The results confirmed the superior nature of the DLC coating, with less surface roughness variation for DLC-coated archwires after immersion in a high fluoride ion environment. Friction tests also showed that applying a DLC coating significantly decreased the fretting wear and the coefficient of friction, both in ambient air and artificial saliva. Thus, DLC coatings are recommended to reduce fluoride-induced corrosion and improve orthodontic friction.

  4. Polarized Raman spectroscopy of chemically vapour deposited diamond films

    International Nuclear Information System (INIS)

    Prawer, S.; Nugent, K.W.; Weiser, P.S.

    1994-01-01

    Polarized micro-Raman spectra of chemically vapour deposited diamond films are presented. It is shown that important parameters often extracted from the Raman spectra such as the ratio of the diamond to non-diamond component of the films and the estimation of the level of residual stress depend on the orientation of the diamond crystallites with respect to the polarization of the incident laser beam. The dependence originates from the fact that the Raman scattering from the non-diamond components in the films is almost completely depolarized whilst the scattering from the diamond components is strongly polarized. The results demonstrate the importance of taking polarization into account when attempting to use Raman spectroscopy in even a semi-quantitative fashion for the assessment of the purity, perfection and stress in CVD diamond films. 8 refs., 1 tab. 2 figs

  5. Application of heat treatment and dispersive strengthening concept in interlayer deposition to enhance diamond film adherence

    Energy Technology Data Exchange (ETDEWEB)

    Lin Chiiruey [Tatung Inst. of Technol., Taipei (Taiwan, Province of China). Dept. of Mech. Eng.; Kuo Chengtzu; Chang Rueyming [Institute of Materials Science and Engineering, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30050 (Taiwan, Province of China)

    1997-10-31

    Two different deposition processes were carried out to enhance adherence of diamond films on WC+3-5%Co substrate with Ti-Si as the interlayer. One process can be called two-step diamond deposition process. Another process can be called interlayer heat treatment process. Diamond films were deposited by a microwave plasma chemical vapor deposition system. Ti and Si interlayer are deposited by DC sputter and an E-gun, respectively. Film morphologies, interface structure and film quality were examined by SEM, XRD, Auger electron spectroscopy and Raman spectroscopy. The residual stresses and adhesion strengths of the films were determined by Raman spectroscopy and indentation adhesion testing, respectively. Comparing the regular one-step diamond deposition process with the present two different new processes, the average dP/dX values, which are a measure of the adherence of the film, are 354 kgf/mm, 494 kgf/mm and 787 kgf/mm, respectively. In other words, the interlayer heat treatment process gives the best film adherence on average. For the two-step diamond deposition process, the interlayer thickness and the percent diamond surface coverage of the first diamond deposition step are the main parameters, and there exists an optimum Ti thickness and percent diamond coverage for the best film adherence. The main contribution to better film adherence is not a large difference in residual stress, but is due to the following reasons. The interlayer heat treatment can transform amorphous Si to polycrystalline Si, and may form strong TiC and SiC bonding. The polycrystalline Si and the diamond particles from the first diamond deposition step can be an effective seeds to enhance diamond nucleation. (orig.) 11 refs.

  6. Bacterial adherence on fluorinated carbon based coatings deposited on polyethylene surfaces

    International Nuclear Information System (INIS)

    Terriza, A; Del Prado, G; Perez, A Ortiz; Martinez, M J; Puertolas, J A; Manso, D Molina; Gonzalez-Elipe, A R; Yubero, F; Barrena, E Gomez; Esteban, J

    2010-01-01

    Development of intrinsically antibacterial surfaces is of key importance in the context of prostheses used in orthopaedic surgery. In this work we present a thorough study of several plasma based coatings that may be used with this functionality: diamond like carbon (DLC), fluorine doped DLC (F-DLC) and a high fluorine content carbon-fluor polymer (CF X ). The study correlates the surface chemistry and hydrophobicity of the coating surfaces with their antibacterial performance. The coatings were deposited by RF-plasma assisted deposition at room temperature on ultra high molecular weight polyethylene (UHMWPE) samples. Fluorine content and relative amount of C-C and C-F bond types was monitored by X-ray photoelectron spectroscopy and hydrophobicity by water contact angle measurements. Adherence of Staphylococcus aureus and Staphylococcus epidermidis to non-coated and coated UHMWPE samples was evaluated. Comparisons of the adherence performance were evaluated using a paired t test (two materials) and a Kruskall Wallis test (all the materials). S. aureus was statistically significant (p< 0.001) less adherent to DLC and F-DLC surfaces than S. epidermidis. Both bacteria showed reduction of adherence on DLC/UHMWPE. For S. aureus, reduction of bacterial adherence on F-DLC/UHMWPE was statistically significant respect to all other materials.

  7. Diamond thin films: giving biomedical applications a new shine.

    Science.gov (United States)

    Nistor, P A; May, P W

    2017-09-01

    Progress made in the last two decades in chemical vapour deposition technology has enabled the production of inexpensive, high-quality coatings made from diamond to become a scientific and commercial reality. Two properties of diamond make it a highly desirable candidate material for biomedical applications: first, it is bioinert, meaning that there is minimal immune response when diamond is implanted into the body, and second, its electrical conductivity can be altered in a controlled manner, from insulating to near-metallic. In vitro, diamond can be used as a substrate upon which a range of biological cells can be cultured. In vivo , diamond thin films have been proposed as coatings for implants and prostheses. Here, we review a large body of data regarding the use of diamond substrates for in vitro cell culture. We also detail more recent work exploring diamond-coated implants with the main targets being bone and neural tissue. We conclude that diamond emerges as one of the major new biomaterials of the twenty-first century that could shape the way medical treatment will be performed, especially when invasive procedures are required. © 2017 The Authors.

  8. Optimization of Cvd Diamond Coating Type on Micro Drills in Pcb Machining

    Science.gov (United States)

    Lei, X. L.; He, Y.; Sun, F. H.

    2016-12-01

    The demand for better tools for machining printed circuit boards (PCBs) is increasing due to the extensive usage of these boards in digital electronic products. This paper is aimed at optimizing coating type on micro drills in order to extend their lifetime in PCB machining. First, the tribotests involving micro crystalline diamond (MCD), nano crystalline diamond (NCD) and bare tungsten carbide (WC-Co) against PCBs show that NCD-PCB tribopair exhibits the lowest friction coefficient (0.35) due to the unique nano structure and low surface roughness of NCD films. Thereafter, the dry machining performance of the MCD- and NCD-coated micro drills on PCBs is systematically studied, using diamond-like coating (DLC) and TiAlN-coated micro drills as comparison. The experiments show that the working lives of these micro drills can be ranked as: NCD>TiAlN>DLC>MCD>bare WC-Co. The superior cutting performance of NCD-coated micro drills in terms of the lowest flank wear growth rate, no tool degradation (e.g. chipping, tool tipping) appearance, the best hole quality as well as the lowest feed force may come from the excellent wear resistance, lower friction coefficient against PCB as well as the high adhesive strength on the underneath substrate of NCD films.

  9. Tribological performance of polycrystalline tantalum-carbide-incorporated diamond films on silicon substrates

    Science.gov (United States)

    Ullah, Mahtab; Rana, Anwar Manzoor; Ahmed, E.; Malik, Abdul Sattar; Shah, Z. A.; Ahmad, Naseeb; Mehtab, Ujala; Raza, Rizwan

    2018-05-01

    Polycrystalline tantalum-carbide-incorporated diamond coatings have been made on unpolished side of Si (100) wafer by hot filament chemical vapor deposition process. Morphology of the coatings has been found to vary from (111) triangular-facetted to predominantly (111) square-faceted by increasing the concentration of tantalum carbide. The results have been compared to those of a diamond reference coating with no tantalum content. An increase in roughness has been observed with the increase of tantalum carbide (TaC) due to change in morphology of the diamond films. It is noticed that roughness of the coatings increases as grains become more square-faceted. It is found that diamond coatings involving tantalum carbide are not as resistant as diamond films with no TaC content and the coefficient of friction for such coatings with microcrystalline grains can be manipulated to 0·33 under high vacuum of 10-7 Torr. Such a low friction coefficient value enhances tribological behavior of unpolished Si substrates and can possibly be used in sliding applications.

  10. Near-surface hydrogen depletion of diamond-like carbon films produced by direct ion deposition

    Science.gov (United States)

    Markwitz, Andreas; Gupta, Prasanth; Mohr, Berit; Hübner, René; Leveneur, Jerome; Zondervan, Albert; Becker, Hans-Werner

    2016-03-01

    Amorphous atomically flat diamond-like carbon (DLC) coatings were produced by direct ion deposition using a system based on a Penning ion source, butane precursor gas and post acceleration. Hydrogen depth profiles of the DLC coatings were measured with the 15N R-NRA method using the resonant nuclear reaction 1H(15N, αγ)12C (Eres = 6.385 MeV). The films produced at 3.0-10.5 kV acceleration voltage show two main effects. First, compared to average elemental composition of the film, the near-surface region is hydrogen depleted. The increase of the hydrogen concentration by 3% from the near-surface region towards the bulk is attributed to a growth model which favours the formation of sp2 hybridised carbon rich films in the film formation zone. Secondly, the depth at which the maximum hydrogen concentration is measured increases with acceleration voltage and is proportional to the penetration depth of protons produced by the ion source from the precursor gas. The observed effects are explained by a deposition process that takes into account the contributions of ion species, hydrogen effusion and preferential displacement of atoms during direct ion deposition.

  11. Characterization of laboratory and industrial CrN/CrCN/diamond-like carbon coatings

    Energy Technology Data Exchange (ETDEWEB)

    Silva, F.J.G., E-mail: francisco.silva@eu.ipp.pt [Departamento de Engenharia Mecânica do Instituto Superior de Engenharia do Porto do Instituto Politécnico do Porto, Rua Dr. António Bernardino de Almeida, 431, 4200-072 Porto (Portugal); Martinho, R.P. [Departamento de Engenharia da Escola Superior de Estudos Industriais e de Gestão do Instituto Politécnico do Porto, Rua D. Sancho I, 981, 4480-876 Vila do Conde (Portugal); Baptista, A.P.M. [Departamento de Engenharia Mecânica da Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, s/n, 4200-465 Porto (Portugal)

    2014-01-01

    This work reports on laboratorial and experimental wear behaviour studies about a multi-layered film deposited by PVD (Physical Vapour Deposition) unbalanced magnetron sputtering. The film consists of three different layers: CrN in the bottom, CrCN as intermediate layer and DLC (diamond-like carbon) on the top. Film characterization was done using techniques such as Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, Atomic Force Microscopy and X-ray diffraction. Scratch-tests, nanoindentation analysis and ball-cratering wear tests were used in order to measure the adhesion critical load, hardness and wear coefficient, respectively. Experimental tests were developed letting one to realise the suitability of this film for mould cavities used on injection moulding machines that produce automotive parts in polypropylene reinforced with 30% (wt.) glass fibres, because this composite material performs severe abrasion on injection moulding which brings important challenges to surface wear resistance. Experimental tests revealed that, after 135,000 injection cycles, multi-layer coating improved significantly the performance previously revealed by uncoated samples. The good results achieved by this film can be partially assigned to DLC top layer due to its low friction coefficient. This paper discusses these results, comparing them with some other PVD coatings already tested in the same conditions. - Highlights: • This coating presents a very good adhesion to the P20 steel substrate. • Surface wear performance is largely improved by the use of this coating. • Coating wear resistance is about 58.2 times higher than the uncoated substrate. • This film presents high suitability for application in mould cavities.

  12. Plasmon-Organic Fiber Interactions in Diamond-Like Carbon Coated Nanostructured Gold Films

    DEFF Research Database (Denmark)

    Cielecki, Pawel Piotr; Sobolewska, Elżbieta Karolina; Kostiučenko, Oksana

    2017-01-01

    Gold is the most commonly used plasmonic material, however soft and prone to mechanical deformations. It has been shown that the durability of gold plasmonic substrates can be improved by applying a protective diamond-like carbon (DLC) coating. In this work, we investigate the influence of such p......Gold is the most commonly used plasmonic material, however soft and prone to mechanical deformations. It has been shown that the durability of gold plasmonic substrates can be improved by applying a protective diamond-like carbon (DLC) coating. In this work, we investigate the influence...

  13. Effect of diamond-like carbon coating on corrosion rate of machinery steel HQ 805

    Science.gov (United States)

    Slat, Winda Sanni; Malau, Viktor; Iswanto, Priyo Tri; Sujitno, Tjipto; Suprapto

    2018-04-01

    HQ 805 is known as a super strength alloys steel and widely applied in military equipment and, aircraft components, drilling device and so on. It is due to its excellent behavior in wear, fatigue, high temperature and high speed operating conditions. The weakness of this material is the vulnerablality to corrosion when employed in sour environments where hydrogen sulfide and chlorides are present. To overcome the problems, an effort should be made to improve or enhance the surface properties for a longer service life. There are varieties of coatings developed and used to improve surface material properties. There are several kinds of coating methods; chemical vapour deposition (CVD), physical vapour deposition (PVD), thermochemical treatment, oxidation, or plasma spraying. This paper presents the research result of the influence of Diamond-Like Carbon (DLC) coating deposited using DC plasma enhanced chemical vapor deposition (DC-PECVD) on corrosion rate (by potentiodynamic polarization method) of HQ 805 machinery steel. As a carbon sources, a mixture of argon (Ar) and methane (CH4) with ratio 76% : 24% was used in this experiment. The conditions of experiment were 400 °C of temperature, 1.2 mbar, 1.4 mbar, 1.6 mbar and 1.8 mbar of pressure of process. Investigated surface properties were hardness (microhardness tester), roughness (roughness test), chemical composition (Spectrometer), microstructure (SEM) and corrosion rate (potentiodynamic polarization). It has been found that the optimum condition with the lowest corrosion rate is at a pressure of 1.4 mbar with a deposition duration of 4 hours at a constant temperature of 400 °C. In this condition, the corrosion rate decreases from 12.326 mpy to 4.487 mpy.

  14. Multilayer DLC coatings via alternating bias during magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Li Fengji [School of Mechanical and Aerospace Engineering, Nanyang Technological University (Singapore); Zhang, Sam, E-mail: msyzhang@ntu.edu.sg [School of Mechanical and Aerospace Engineering, Nanyang Technological University (Singapore); Kong Junhua [School of Materials Science and Engineering, Nanyang Technological University (Singapore); Zhang Yujuan [Key Laboratory of Special Functional Material, Henan University (China); Zhang Wali [School of Mechanical and Aerospace Engineering, Nanyang Technological University (Singapore)

    2011-05-31

    To combat the high residual stress problem in monolayer diamond-like carbon coatings, this paper fabricated multilayer diamond-like carbon coatings with alternate soft and hard layers via alternating bias during magnetron sputtering. The surface, cross sectional morphology, bonding structures and mechanical properties are investigated. The atomic force microscopy images indicate low bias results in rougher surface with large graphite clusters and voids suggesting low coating density. The multilayered coatings demonstrate relatively smooth surface stemming from higher bias. The cross sectional images from field emission scanning electron microscopy indicate coating thickness decreases as substrate bias increases and confirm that higher bias results in denser coating. Delamination is observed in monolayer coatings due to high residual stress. The trend of sp{sup 3}/sp{sup 2} fraction estimated by X-ray photoelectron spectroscopy is consistent with that of I{sub D}/I{sub G} ratios from Raman spectra, indicating the change of bonding structure with change of substrate bias. Hardness of multilayer diamond-like carbon coating is comparable to the coatings deposited at low constant bias but the adhesion strength and toughness are significantly improved. Alternately biased sputtering deposition provides an alternative when combination of hardness, toughness and adhesion strength is needed in an all diamond-like carbon coating.

  15. Direct deposition of patterned nanocrystalline CVD diamond using an electrostatic self-assembly method with nanodiamond particles

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung-Koo; Kim, Jong-Hoon; Jeong, Min-Goon; Lim, Dae-Soon [Department of Materials Science and Engineering, Korea University, Anam-Dong 5-1, Seoungbuk-Ku, Seoul 136-713 (Korea, Republic of); Song, Min-Jung, E-mail: dslim@korea.ac.kr [Center for Advanced Device Materials, Korea University, Anam-Dong 5-1, Seoungbuk-Ku, Seoul 136-713 (Korea, Republic of)

    2010-12-17

    Micron-sized and precise patterns of nanocrystalline CVD diamond were fabricated successfully on substrates using dispersed nanodiamond particles, charge connection by electrostatic self-assembly, and photolithography processes. Nanodiamond particles which had been dispersed using an attritional milling system were attached electrostatically on substrates as nuclei for diamond growth. In this milling process, poly sodium 4-styrene sulfonate (PSS) was added as an anionic dispersion agent to produce the PSS/nanodiamond conjugates. Ultra dispersed nanodiamond particles with a {zeta}-potential and average particle size of - 60.5 mV and {approx} 15 nm, respectively, were obtained after this milling process. These PSS/nanodiamond conjugates were attached electrostatically to a cationic polyethyleneimine (PEI) coated surface on to which a photoresist had been patterned in an aqueous solution of the PSS/nanodiamond conjugated suspension. A selectively seeded area was formed successfully using the above process. A hot filament chemical vapor deposition system was used to synthesize the nanocrystalline CVD diamond on the seeded area. Micron-sized, thin and precise nanocrystalline CVD diamond patterns with a high nucleation density (3.8 {+-} 0.4 x 10{sup 11} cm{sup -2}) and smooth surface were consequently fabricated.

  16. Direct deposition of patterned nanocrystalline CVD diamond using an electrostatic self-assembly method with nanodiamond particles

    International Nuclear Information System (INIS)

    Lee, Seung-Koo; Kim, Jong-Hoon; Jeong, Min-Goon; Lim, Dae-Soon; Song, Min-Jung

    2010-01-01

    Micron-sized and precise patterns of nanocrystalline CVD diamond were fabricated successfully on substrates using dispersed nanodiamond particles, charge connection by electrostatic self-assembly, and photolithography processes. Nanodiamond particles which had been dispersed using an attritional milling system were attached electrostatically on substrates as nuclei for diamond growth. In this milling process, poly sodium 4-styrene sulfonate (PSS) was added as an anionic dispersion agent to produce the PSS/nanodiamond conjugates. Ultra dispersed nanodiamond particles with a ζ-potential and average particle size of - 60.5 mV and ∼ 15 nm, respectively, were obtained after this milling process. These PSS/nanodiamond conjugates were attached electrostatically to a cationic polyethyleneimine (PEI) coated surface on to which a photoresist had been patterned in an aqueous solution of the PSS/nanodiamond conjugated suspension. A selectively seeded area was formed successfully using the above process. A hot filament chemical vapor deposition system was used to synthesize the nanocrystalline CVD diamond on the seeded area. Micron-sized, thin and precise nanocrystalline CVD diamond patterns with a high nucleation density (3.8 ± 0.4 x 10 11 cm -2 ) and smooth surface were consequently fabricated.

  17. Wear and Friction Characteristics of AlN/Diamond-Like Carbon Hybrid Coatings on Aluminum Alloy

    Science.gov (United States)

    Nakamura, Masashi; Kubota, Sadayuki; Suzuki, Hideto; Haraguchi, Tadao

    2015-10-01

    The use of diamond-like carbon (DLC) coatings has the potential to greatly improve the wear resistance and friction of aluminum alloys, but practical application has so far been limited by poor adhesion due to large difference in hardness and elasticity between the two materials. This study investigates the deposition of DLC onto an Al-alloy using an intermediate AlN layer with a graded hardness to create a hybrid coating. By controlling the hardness of the AlN film, it was found that the wear life of the DLC film could be improved 80-fold compared to a DLC film deposited directly onto Al-alloy. Furthermore, it was demonstrated through finite element simulation that creating a hardness gradient in the AlN intermediate layer reduces the distribution of stress in the DLC film, while also increasing the force of adhesion between the DLC and AlN layers. Given that both the DLC and AlN films were deposited using the same unbalanced magnetron sputtering method, this process is considered to represent a simple and effective means of improving the wear resistance of Al-alloy components commonly used within the aerospace and automotive industries.

  18. Scientific Fundamentals and Technological Development of Novel Biocompatible/Corrosion Resistant Ultrananocrystalline Diamond (UNCD) Coating Enabling Next Generation Superior Metal-Based Dental Implants

    Science.gov (United States)

    Kang, Karam

    Current Ti-based dental implants exhibit failure (2-10%), due to various mechanisms, including chemical corrosion of the surface of the TiO2 naturally covered Ti-based implants. This thesis focused on developing a unique biocompatible/bio-inert/corrosion resistant/low cost Ultrananocrystalline Diamond (UNCD) coating (with 3-5 nm grain size) for encapsulation of Tibased micro-implants to potentially eliminate the corrosion/mechanical induced failure of current commercial Ti-based dental implants. Microwave Plasma Chemical Vapor Deposition (MPCVD) and Hot Filament Chemical Vapor Deposition (HFCVD) processes were used to grow UNCD coatings. The surface topography and chemistry of UNCD coatings were characterized using scanning electron microscopy (SEM), Raman, and X-ray photoelectron spectroscopies (XPS) respectively. In conclusion, this thesis contributed to establish the optimal conditions to grow UNCD coatings on the complex 3-D geometry of Ti-based micro-implants, with geometry similar to real implants, relevant to developing UNCD-coated Ti-based dental implants with superior mechanical/chemical performance than current Ti-based implants.

  19. Influence of chemical pretreatment of hard metal substrates for diamond deposition

    International Nuclear Information System (INIS)

    Buck, V.; Kluwe, H.; Schmiler, B.; Deuerler, F.

    2001-01-01

    Diamond coated cutting tools are of increasing importance in the fields of high speed cutting, dry machining or machining of special materials such as metal-matrix-composites. A well known problem is the poor adhesion of diamond films on hard metals due to the Co- or Ni-binder that catalyzes the formation of graphite. Several methods - such as the application of intermediate layers or mechanical or chemical pretreatment of the hard metal substrate - have been developed to overcome this effect. Usually chemical pretreatment is used in order to reduce the concentration of binder phase on the surface that is to be coated. Surprisingly pretreatment with agents such as Murakami's solution result in improved adhesion and nucleation of diamond films while the concentration of the binder phase on the surface is enhanced. This 'contradiction' can be explained by proving that the surface is converted into a very thin oxide/hydroxide film. (author)

  20. Architectural design of diamond-like carbon coatings for long-lasting joint replacements.

    Science.gov (United States)

    Liu, Yujing; Zhao, Xiaoli; Zhang, Lai-Chang; Habibi, Daryoush; Xie, Zonghan

    2013-07-01

    Surface engineering through the application of super-hard, low-friction coatings as a potential approach for increasing the durability of metal-on-metal replacements is attracting significant attention. In this study innovative design strategies are proposed for the development of diamond-like-carbon (DLC) coatings against the damage caused by wear particles on the joint replacements. Finite element modeling is used to analyze stress distributions induced by wear particles of different sizes in the newly-designed coating in comparison to its conventional monolithic counterpart. The critical roles of architectural design in regulating stress concentrations and suppressing crack initiation within the coatings is elucidated. Notably, the introduction of multilayer structure with graded modulus is effective in modifying the stress field and reducing the magnitude and size of stress concentrations in the DLC diamond-like-carbon coatings. The new design is expected to greatly improve the load-carrying ability of surface coatings on prosthetic implants, in addition to the provision of damage tolerance through crack arrest. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Thermodynamic analysis of processes proceeding on (111) faces of diamond during chemical vapour deposition

    International Nuclear Information System (INIS)

    Piekarczyk, W.; Prawer, S.

    1992-01-01

    Chemically vapour deposited diamond is commonly synthesized from activated hydrogen-rich, carbon/hydrogen gas mixtures under conditions which should, from a thermodynamic equilibrium point of view, favour the production of graphite. Much remains to be understood about why diamond, and not graphite, forms under these conditions. However, it is well known that the presence of atomic hydrogen, is crucial to the success of diamond deposition. As part of an attempt to better understand the deposition process, a thermodynamic analysis of the process was performed on diamond (111) faces in hydrogen rich environments. It is shown that the key role of atomic hydrogen is to inhibit the reconstruction of the (111) face to an sp 2 -bonded structure, which would provide a template for graphite, rather than diamond formation. The model correctly predicts experimentally determined trends in growth rate and diamond film quality as a function of methane concentration in the stating gas mixture. 17 refs., 4 figs

  2. Chemical vapour deposition synthetic diamond: materials, technology and applications

    International Nuclear Information System (INIS)

    Balmer, R S; Brandon, J R; Clewes, S L; Dhillon, H K; Dodson, J M; Friel, I; Inglis, P N; Madgwick, T D; Markham, M L; Mollart, T P; Perkins, N; Scarsbrook, G A; Twitchen, D J; Whitehead, A J; Wilman, J J; Woollard, S M

    2009-01-01

    Substantial developments have been achieved in the synthesis of chemical vapour deposition (CVD) diamond in recent years, providing engineers and designers with access to a large range of new diamond materials. CVD diamond has a number of outstanding material properties that can enable exceptional performance in applications as diverse as medical diagnostics, water treatment, radiation detection, high power electronics, consumer audio, magnetometry and novel lasers. Often the material is synthesized in planar form; however, non-planar geometries are also possible and enable a number of key applications. This paper reviews the material properties and characteristics of single crystal and polycrystalline CVD diamond, and how these can be utilized, focusing particularly on optics, electronics and electrochemistry. It also summarizes how CVD diamond can be tailored for specific applications, on the basis of the ability to synthesize a consistent and engineered high performance product.

  3. Effect of substrate bias voltage on tensile properties of single crystal silicon microstructure fully coated with plasma CVD diamond-like carbon film

    Science.gov (United States)

    Zhang, Wenlei; Hirai, Yoshikazu; Tsuchiya, Toshiyuki; Tabata, Osamu

    2018-06-01

    Tensile strength and strength distribution in a microstructure of single crystal silicon (SCS) were improved significantly by coating the surface with a diamond-like carbon (DLC) film. To explore the influence of coating parameters and the mechanism of film fracture, SCS microstructure surfaces (120 × 4 × 5 μm3) were fully coated by plasma enhanced chemical vapor deposition (PECVD) of a DLC at five different bias voltages. After the depositions, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), thermal desorption spectrometry (TDS), surface profilometry, atomic force microscope (AFM) measurement, and nanoindentation methods were used to study the chemical and mechanical properties of the deposited DLC films. Tensile test indicated that the average strength of coated samples was 13.2-29.6% higher than that of the SCS sample, and samples fabricated with a -400 V bias voltage were strongest. The fracture toughness of the DLC film was the dominant factor in the observed tensile strength. Deviations in strength were reduced with increasingly negative bias voltage. The effect of residual stress on the tensile properties is discussed in detail.

  4. Plasma boriding of a cobalt–chromium alloy as an interlayer for nanostructured diamond growth

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, Jamin M.; Jubinsky, Matthew; Catledge, Shane A., E-mail: catledge@uab.edu

    2015-02-15

    Highlights: • Metal-boride layer creates a compatible surface for NSD deposition. • PECVD boriding on CoCrMo produces robust metal-boride layer. • Deposition temperature comparison shows 750 °C boriding masks surface cobalt. • EDS shows boron diffusion as well as deposition. • Nanoindentation hardness of CoCrMo substantially increases after boriding. - Abstract: Chemical vapor deposited (CVD) diamond coatings can potentially improve the wear resistance of cobalt–chromium medical implant surfaces, but the high cobalt content in these alloys acts as a catalyst to form graphitic carbon. Boriding by high temperature liquid baths and powder packing has been shown to improve CVD diamond compatibility with cobalt alloys. We use the microwave plasma-enhanced (PE) CVD process to deposit interlayers composed primarily of the borides of cobalt and chromium. The use of diborane (B{sub 2}H{sub 6}) in the plasma feedgas allows for the formation of a robust boride interlayer for suppressing graphitic carbon during subsequent CVD of nano-structured diamond (NSD). This metal–boride interlayer is shown to be an effective diffusion barrier against elemental cobalt for improving nucleation and adhesion of NSD coatings on a CoCrMo alloy. Migration of elemental cobalt to the surface of the interlayer is significantly reduced and undetectable on the surface of the subsequently-grown NSD coating. The effects of PECVD boriding are compared for a range of substrate temperatures and deposition times and are evaluated using glancing-angle X-ray diffraction (XRD), cross-sectional scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and micro-Raman spectroscopy. Boriding of CoCrMo results in adhered nanostructured diamond coatings with low surface roughness.

  5. Effect of absorbing coating on ablation of diamond by IR laser pulses

    Science.gov (United States)

    Kononenko, T. V.; Pivovarov, P. A.; Khomich, A. A.; Khmel'nitskii, R. A.; Konov, V. I.

    2018-03-01

    We study the possibility of increasing the efficiency and quality of laser ablation microprocessing of diamond by preliminary forming an absorbing layer on its surface. The laser pulses having a duration of 1 ps and 10 ns at a wavelength of 1030 nm irradiate the polycrystalline diamond surface coated by a thin layer of titanium or graphite. We analyse the dynamics of the growth of the crater depth as a function of the number of pulses and the change in optical transmission of the ablated surface. It is found that under irradiation by picosecond pulses the preliminary graphitisation allows one to avoid the laser-induced damage of the internal diamond volume until the appearance of a self-maintained graphitised layer. The absorbing coating (both graphite and titanium) much stronger affects ablation by nanosecond pulses, since it reduces the ablation threshold by more than an order of magnitude and allows full elimination of a laser-induced damage of deep regions of diamond and uncontrolled explosive ablation in the nearsurface layer.

  6. Flexible diamond-like carbon thin film coated rubbers: fundamentals and applications

    NARCIS (Netherlands)

    Pei, Y.T.

    2015-01-01

    Dynamic rubber seals are major sources of friction of lubrication systems and bearings, which may take up to 75% of the total friction. The solution we present is to coat rubbers with diamond-like carbon (DLC) thin film, by which the coefficient of friction is reduced to less than one tenth. Coating

  7. Deposition and Characterization of Hermetic, Biocompatible Thin Film Coatings for Implantable, Electrically Active Devices

    Science.gov (United States)

    Sweitzer, Robyn K.

    Retinal prostheses may be used to support patients suffering from Age-related macular degeneration or retinitis pigmentosa. A hermetic encapsulation of the poly(imide )-based prosthesis is important in order to prevent the leakage of water and ions into the electric circuitry embedded in the poly(imide) matrix. The deposition of amorphous aluminum oxide (by sputtering) and diamond like carbon (by pulsed laser ablation and vacuum arc vapor deposition) were studied for the application in retinal prostheses. The resulting thin films were characterized for composition, thickness, adhesion and smoothness by scanning electron microscopy-energy dispersive spectroscopy, atomic force microscopy, profilometry and light microscopy. Electrical stability was evaluated and found to be good. The as-deposited films prevented incursion of salinated fluids into the implant over two (2) three month trials soaking in normal saline at body temperature, Biocompatibility was tested in vivo by implanting coated specimen subretinally in the eye of Yucatan pigs. While amorphous aluminum oxide is more readily deposited with sufficient adhesion quality, biocompatibility studies showed a superior behavior of diamond-like carbon. Amorphous aluminum oxide had more adverse effects and caused more severe damage to the retinal tissue.

  8. Room-temperature deposition of diamond-like carbon field emitter on flexible substrates

    International Nuclear Information System (INIS)

    Chen, H.; Iliev, M.N.; Liu, J.R.; Ma, K.B.; Chu, W.-K.; Badi, N.; Bensaoula, A.; Svedberg, E.B.

    2006-01-01

    Room-temperature fabrication of diamond-like carbon electron field emitters on flexible polyimide substrate is reported. These thin film field emitters are made using an Ar gas cluster ion beam assisted C 6 vapor deposition method. The bond structure of the as-deposited diamond-like carbon film was studied using Raman spectroscopy. The field emission characteristics of the deposited films were also measured. Electron current densities over 15 mA/cm 2 have been recorded under an electrical field of about 65 V/μm. These diamond-like carbon field emitters are easy and inexpensive to fabricate. The results are promising for flexible field-emission fabrication without the need of complex patterning and tip shaping as compared to the Spindt-type field emitters

  9. Influence of high temperature annealing on the structure, hardness and tribological properties of diamond-like carbon and TiAlSiCN nanocomposite coatings

    International Nuclear Information System (INIS)

    Xie, Z.W.; Wang, L.P.; Wang, X.F.; Huang, L.; Lu, Y.; Yan, J.C.

    2011-01-01

    Diamond-like carbon (DLC) and TiAlSiCN nanocomposite coatings were synthesized and annealed at different temperatures in a vacuum environment. The microstructure, hardness and tribological properties of as-deposited and annealed DLC-TiAlSiCN nanocomposite coatings were characterized by X-ray diffraction, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), Raman spectroscopy, nano-indentation and friction tests. The TEM results reveal that the as-deposited DLC-TiAlSiCN coating has a unique nanocomposite structure consisting of TiCN nanocrystals embedded in an amorphous matrix consisting of a-Si 3 N 4 , a-SiC, a-CN and DLC, and the structure changed little after annealing at 800 °C. However, XPS and Raman results show that an obvious graphitization of the DLC phase occurred during the annealing process and it worsened with annealing temperature. Because of the graphitization, the hardness of the DLC-TiAlSiCN coating after annealing at 800 °C decreased from 45 to 36 GPa. In addition, the DLC-TiAlSiCN coating after annealing at 800 °C has a similar friction coefficient to the as-deposited coating.

  10. Near-surface hydrogen depletion of diamond-like carbon films produced by direct ion deposition

    Energy Technology Data Exchange (ETDEWEB)

    Markwitz, Andreas, E-mail: A.Markwitz@gns.cri.nz [GNS Science, Lower Hutt (New Zealand); The MacDiarmid Institute for Advanced Materials and Nanotechnology (New Zealand); Gupta, Prasanth [GNS Science, Lower Hutt (New Zealand); The MacDiarmid Institute for Advanced Materials and Nanotechnology (New Zealand); Mohr, Berit [GNS Science, Lower Hutt (New Zealand); Hübner, René [Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf (Germany); Leveneur, Jerome; Zondervan, Albert [GNS Science, Lower Hutt (New Zealand); Becker, Hans-Werner [RUBION, Ruhr-University Bochum (Germany)

    2016-03-15

    Amorphous atomically flat diamond-like carbon (DLC) coatings were produced by direct ion deposition using a system based on a Penning ion source, butane precursor gas and post acceleration. Hydrogen depth profiles of the DLC coatings were measured with the 15N R-NRA method using the resonant nuclear reaction {sup 1}H({sup 15}N, αγ){sup 12}C (E{sub res} = 6.385 MeV). The films produced at 3.0–10.5 kV acceleration voltage show two main effects. First, compared to average elemental composition of the film, the near-surface region is hydrogen depleted. The increase of the hydrogen concentration by 3% from the near-surface region towards the bulk is attributed to a growth model which favours the formation of sp{sup 2} hybridised carbon rich films in the film formation zone. Secondly, the depth at which the maximum hydrogen concentration is measured increases with acceleration voltage and is proportional to the penetration depth of protons produced by the ion source from the precursor gas. The observed effects are explained by a deposition process that takes into account the contributions of ion species, hydrogen effusion and preferential displacement of atoms during direct ion deposition.

  11. Real time monitoring of filament-assisted chemically vapor deposited diamond by spectroscopic ellipsometry

    International Nuclear Information System (INIS)

    Yue Cong; An, I.; Vedam, K.; Collins, R.W.; Nguyen, H.V.; Messier, R.

    1991-01-01

    Spectroscopic ellipsometry over the range 1.5-4.5 eV was applied as a real time probe of the processes occurring in the initial nucleation of thin film diamond by heated-filament assisted chemical vapor deposition. Using both untreated and diamond-polished c-Si substrates, as well as both carburized and uncarburized tungsten filaments, it was possible to separate and characterize competing phenomena, including the increase in surface temperature induced by filament ignition, the formation of carbide layers, contamination of the substrate by tungsten from the filament, annealing of diamond polishing damage, and, finally, diamond nucleation. An accurate measurement of the true temperature of the substrate surface averaged over the top 500 A can be obtained from the energy position of critical points in the c-Si band structure. For diamond deposition, we operated with an initial excess flow of CH 4 to stimulate nucleation. We applied real time feedback and manual control to reduce the CH 4 flow in the first monolayers of deposition. The thickness of diamond and an estimate of its nucleation density can be obtained from real time spectra, and the latter was in good agreement with that obtained from scanning electron microscopy. (orig.)

  12. Sticking non-stick: Surface and Structure control of Diamond-like Carbon in Plasma Enhanced Chemical Vapour Deposition

    Science.gov (United States)

    Jones, B. J.; Nelson, N.

    2016-10-01

    This short review article explores the practical use of diamond-like carbon (DLC) produced by plasma enhanced chemical vapour deposition (PECVD). Using as an example issues relating to the DLC coating of a hand-held surgical device, we draw on previous works using atomic force microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, tensiometry and electron paramagnetic resonance. Utilising data from these techniques, we examine the surface structure, substrate-film interface and thin film microstructure, such as sp2/sp3 ratio (graphitic/diamond-like bonding ratio) and sp2 clustering. We explore the variations in parameters describing these characteristics, and relate these to the final device properties such as friction, wear resistance, and diffusion barrier integrity. The material and device characteristics are linked to the initial plasma and substrate conditions.

  13. Sticking non-stick: Surface and Structure control of Diamond-like Carbon in Plasma Enhanced Chemical Vapour Deposition

    International Nuclear Information System (INIS)

    Jones, B J; Nelson, N

    2016-01-01

    This short review article explores the practical use of diamond-like carbon (DLC) produced by plasma enhanced chemical vapour deposition (PECVD). Using as an example issues relating to the DLC coating of a hand-held surgical device, we draw on previous works using atomic force microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, tensiometry and electron paramagnetic resonance. Utilising data from these techniques, we examine the surface structure, substrate-film interface and thin film microstructure, such as sp 2 /sp 3 ratio (graphitic/diamond-like bonding ratio) and sp 2 clustering. We explore the variations in parameters describing these characteristics, and relate these to the final device properties such as friction, wear resistance, and diffusion barrier integrity. The material and device characteristics are linked to the initial plasma and substrate conditions. (paper)

  14. Crack formation mechanisms during micro and macro indentation of diamond-like carbon coatings on elastic-plastic substrates

    DEFF Research Database (Denmark)

    Thomsen, N.B.; Fischer-Cripps, A.C.; Swain, M.V.

    1998-01-01

    of cracking and the fracture mechanisms taking place. In the study various diamond-like carbon (DLC) coatings deposited onto stainless steel and tool steel were investigated. Results primarily for one DLC system will be presented here. (C) 1998 Published by Elsevier Science S.A. All rights reserved.......In the present study crack formation is investigated on both micro and macro scale using spherical indenter tips. in particular, systems consisting of elastic coatings that are well adhered to elastic-plastic substrates are studied. Depth sensing indentation is used on the micro scale and Rockwell...... indentation on the macro scale. The predominant driving force for coating failure and crack formation during indentation is plastic deformation of the underlying substrate. The aim is to relate the mechanisms creating both delamination and cohesive cracking on both scales with fracture mechanical models...

  15. Ultrananocrystalline diamond film as an optimal cell interface for biomedical applications.

    Science.gov (United States)

    Bajaj, Piyush; Akin, Demir; Gupta, Amit; Sherman, Debby; Shi, Bing; Auciello, Orlando; Bashir, Rashid

    2007-12-01

    Surfaces of materials that promote cell adhesion, proliferation, and growth are critical for new generation of implantable biomedical devices. These films should be able to coat complex geometrical shapes very conformally, with smooth surfaces to produce hermetic bioinert protective coatings, or to provide surfaces for cell grafting through appropriate functionalization. Upon performing a survey of desirable properties such as chemical inertness, low friction coefficient, high wear resistance, and a high Young's modulus, diamond films emerge as very attractive candidates for coatings for biomedical devices. A promising novel material is ultrananocrystalline diamond (UNCD) in thin film form, since UNCD possesses the desirable properties of diamond and can be deposited as a very smooth, conformal coating using chemical vapor deposition. In this paper, we compared cell adhesion, proliferation, and growth on UNCD films, silicon, and platinum films substrates using different cell lines. Our results showed that UNCD films exhibited superior characteristics including cell number, total cell area, and cell spreading. The results could be attributed to the nanostructured nature or a combination of nanostructure/surface chemistry of UNCD, which provides a high surface energy, hence promoting adhesion between the receptors on the cell surface and the UNCD films.

  16. Study on the Microstructure and Electrical Properties of Boron and Sulfur Codoped Diamond Films Deposited Using Chemical Vapor Deposition

    Directory of Open Access Journals (Sweden)

    Zhang Jing

    2014-01-01

    Full Text Available The atomic-scale microstructure and electron emission properties of boron and sulfur (denoted as B-S codoped diamond films grown on high-temperature and high-pressure (HTHP diamond and Si substrates were investigated using atom force microscopy (AFM, scanning tunneling microscopy (STM, secondary ion mass spectroscopy (SIMS, and current imaging tunneling spectroscopy (CITS measurement techniques. The films grown on Si consisted of large grains with secondary nucleation, whereas those on HTHP diamond are composed of well-developed polycrystalline facets with an average size of 10–50 nm. SIMS analyses confirmed that sulfur was successfully introduced into diamond films, and a small amount of boron facilitated sulfur incorporation into diamond. Large tunneling currents were observed at some grain boundaries, and the emission character was better at the grain boundaries than that at the center of the crystal. The films grown on HTHP diamond substrates were much more perfect with higher quality than the films deposited on Si substrates. The local I-V characteristics for films deposited on Si or HTHP diamond substrates indicate n-type conduction.

  17. Morphology and structure of Ti-doped diamond films prepared by microwave plasma chemical vapor deposition

    Science.gov (United States)

    Liu, Xuejie; Lu, Pengfei; Wang, Hongchao; Ren, Yuan; Tan, Xin; Sun, Shiyang; Jia, Huiling

    2018-06-01

    Ti-doped diamond films were deposited through a microwave plasma chemical vapor deposition (MPCVD) system for the first time. The effects of the addition of Ti on the morphology, microstructure and quality of diamond films were systematically investigated. Secondary ion mass spectrometry results show that Ti can be added to diamond films through the MPCVD system using tetra n-butyl titanate as precursor. The spectra from X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy and the images from scanning electron microscopy of the deposited films indicate that the diamond phase clearly exists and dominates in Ti-doped diamond films. The amount of Ti added obviously influences film morphology and the preferred orientation of the crystals. Ti doping is beneficial to the second nucleation and the growth of the (1 1 0) faceted grains.

  18. Field electron emission characteristics of chemical vapour deposition diamond films with controlled sp2 phase concentration

    International Nuclear Information System (INIS)

    Lu, X.; Yang, Q.; Xiao, C.; Hirose, A.

    2008-01-01

    Diamond films were synthesized in a microwave plasma-enhanced chemical vapour deposition reactor. The microstructure and surface morphology of deposited films were characterized by Raman spectroscope and scanning electron microscope. The sp 2 phase concentration in diamond films was varied and its effect on the field electron emission (FEE) properties was investigated. Diamond films deposited under higher methane concentration exhibit better FEE property including lower turn-on electric field and larger emission current. The predominating factor modifying the FEE property is presumed to be the increase of sp 2 phase concentration. The influence of bias voltage on the FEE property of diamond films is not monotonic. Postgrowth acid treatment reduces the sp 2 phase content in diamond films without changing diamond grain sizes. The corresponding FEE property was degraded

  19. Evaluation of resistance of diamond-like carbon coating to the corpuscular radiation in outer space conditions

    Science.gov (United States)

    Tomilova, Elizaveta; Bashkov, Valeriy; Mikhalev, Pavel; Fedorchenko, Alexander; Volkova, Yana

    2015-02-01

    The purpose of this work was to research the resistance of thin coatings to the effects of corpuscular radiation, as well as evaluation speed etching of diamond-like films with different content of diamond phase. There were two samples of monocrystalline silicon with DLC coating. To evaluate the resistance, two groups of grooves were etched on each sample. The depth was then measured to calculate a relative etching ratio of DLC coating. The resistance was determined to be four times that of silicon.

  20. Review: Plasma-enhanced chemical vapor deposition of nanocrystalline diamond

    Directory of Open Access Journals (Sweden)

    Katsuyuki Okada

    2007-01-01

    Full Text Available Nanocrystalline diamond films have attracted considerable attention because they have a low coefficient of friction and a low electron emission threshold voltage. In this paper, the author reviews the plasma-enhanced chemical vapor deposition (PE-CVD of nanocrystalline diamond and mainly focuses on the growth of nanocrystalline diamond by low-pressure PE-CVD. Nanocrystalline diamond particles of 200–700 nm diameter have been prepared in a 13.56 MHz low-pressure inductively coupled CH4/CO/H2 plasma. The bonding state of carbon atoms was investigated by ultraviolet-excited Raman spectroscopy. Electron energy loss spectroscopy identified sp2-bonded carbons around the 20–50 nm subgrains of nanocrystalline diamond particles. Plasma diagnostics using a Langmuir probe and the comparison with plasma simulation are also reviewed. The electron energy distribution functions are discussed by considering different inelastic interaction channels between electrons and heavy particles in a molecular CH4/H2 plasma.

  1. Novel morphology of chemical vapor deposited diamond films

    Energy Technology Data Exchange (ETDEWEB)

    Tang, C.J. [I3N and Department of Physics, University of Aveiro (Portugal); Jiangsu Key Laboratory for Advanced Functional Materials and Department of Physics, Changshu Institute of Technology, Changshu (China); TEMA and Department of Mechanical Engineering, University of Aveiro (Portugal); Fernandes, A.J.S.; Abe, I.; Pinto, J.L. [I3N and Department of Physics, University of Aveiro (Portugal); Gracio, J. [TEMA and Department of Mechanical Engineering, University of Aveiro (Portugal); Buijnsters, J.G. [Institute for Molecules and Materials (IMM), Radboud University Nijmegen (Netherlands)

    2010-04-15

    We have obtained simultaneously nanocrystalline and {l_brace}100{r_brace} faceted large-grained polycrystalline diamond films not only on different substrates but also on the same substrate in only one deposition run using a novel approach for substrate arrangement. Furthermore, interesting unusual morphologies and microstructures composed by non-faceted nanostructures and terminated with large smooth {l_brace}100{r_brace} facet-like belt are found near the edges of the top square sample. The morphology variation is likely caused by the so called edge effect, where a strong variation in temperature is also present. We have modelled the temperature distribution on the substrates by computer simulations using the finite element method. The novel feature, namely the coexistence of oval non-faceted nanocrystalline diamond grains and large smooth {l_brace}100{r_brace} facet-like belt in one diamond grain, is in the transition from {l_brace}100{r_brace} faceted polycrystalline diamond to cauliflower-like nanocrystalline diamond. The formation mechanism is discussed based on the temperature analysis and other simulation results described in the literature. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  2. Diamond-like carbon prepared by pulsed laser deposition with ion bombardment: physical properties

    Science.gov (United States)

    Písařík, P.; Mikšovský, J.; Remsa, J.; Zemek, J.; Tolde, Z.; Jelínek, M.

    2018-01-01

    Diamond-like carbon (DLC) and titanium-doped DLC thin films were prepared by unique hybrid system consisting of pulsed laser deposition, ion source (bombardment) and magnetron sputtering. The influence of deposition parameters (ion energies, deposition pressures and magnetron power) on composition and physical properties was studied. Composition and sp 3/ sp 2 ratio were determined by XPS. sp 3/ sp 2 ratio was in the range from 1.4 to 2.2 for undoped DLC and from 3.4 to 4.8 for Ti-DLC. AFM showed that the layers were smooth, but with small amounts of random droplets. The measurements of the contact angle and determination of surface free energy were made for water, diiodomethane and ethylene glycol. Hardness and reduced Young's modulus varied from 20 to 31 GPa and from 182 to 276 GPa, respectively. Film adhesion was determined by scratch test; L C3 reached 23 N for DLC and 27 N for TiDLC. Optimization of sp 3/ sp 2 ratio, hardness and adhesion to biomedical alloys will advance the DLC coatings usability in the field of implantology.

  3. Effect of tetramethylsilane flow on the deposition and tribological behaviors of silicon doped diamond-like carbon rubbed against poly(oxymethylene)

    Science.gov (United States)

    Deng, Xingrui; Lim, Yankuang; Kousaka, Hiroyuki; Tokoroyama, Takayuki; Umehara, Noritsugu

    2014-11-01

    In this study, silicon doped diamond-like carbon (Si-DLC) was deposited on stainless steel (JIS SUS304) by using surface wave-excited plasma (SWP). The effects of tetramethylsilane (TMS) flow on the composition, topography, mechanical properties and tribological behavior were investigated. Pin-on-disc tribo-meter was used to investigate the tribological behavior of the Si-DLC coating rubbed against poly(oxymethylene) (POM). The results show that the deposition rate, roughness of Si-DLC increased and the hardness of Si-DLC decreased with the increase of TMS flow rate from 2 to 4 sccm; the roughness increase therein led to the increase of ploughing term of friction. The increase of adhesion term was also seen with the increase of TMS flow rate, being attributed to the decrease of hydrogen concentration in the coating. It was considered that more POM transferred onto the Si-DLC deposited at higher TMS flow rate due to larger heat generation by friction.

  4. High rate operation of micro-strip gas chambers on diamond-coated glass

    CERN Document Server

    Bouclier, Roger; Million, Gilbert; Ropelewski, Leszek; Sauli, Fabio; Temmel, T; Cooke, R A; Donnel, S; Sastri, S A; Sonderer, N

    1996-01-01

    Very high rate operation of micro­strip gas chambers can be achieved using slightly conducting substrates. We describe preliminary measurements realized with detectors manufactured on boro-silicate glass coated, before the photo-lithographic processing, with a diamond layer having a surface resistivity of around 1014 ‡/o. Stable medium-term operation, and a rate capability largely exceeding the one obtained with identical plates manufactured on uncoated glass are demonstrated. If these results are confirmed by long-term measurements the diamond coating technology appears very attractive since it allows, with a moderate cost overhead, to use thin, commercially available glass with the required surface quality for the large-scale production of gas micro-strip detectors.

  5. A comparison of diamond growth rate using in-liquid and conventional plasma chemical vapor deposition methods

    International Nuclear Information System (INIS)

    Takahashi, Yoshiyuki; Toyota, Hiromichi; Nomura, Shinfuku; Mukasa, Shinobu; Inoue, Toru

    2009-01-01

    In order to make high-speed deposition of diamond effective, diamond growth rates for gas-phase microwave plasma chemical vapor deposition and in-liquid microwave plasma chemical vapor deposition are compared. A mixed gas of methane and hydrogen is used as the source gas for the gas-phase deposition, and a methanol solution of ethanol is used as the source liquid for the in-liquid deposition. The experimental system pressure is in the range of 60-150 kPa. While the growth rate of diamond increases as the pressure increases, the amount of input microwave energy per unit volume of diamond is 1 kW h/mm 3 regardless of the method used. Since the in-liquid deposition method provides a superior cooling effect through the evaporation of the liquid itself, a higher electric input power can be applied to the electrodes under higher pressure environments. The growth rate of in-liquid microwave plasma chemical vapor deposition process is found to be greater than conventional gas-phase microwave plasma chemical vapor deposition process under the same pressure conditions.

  6. A comparison of diamond growth rate using in-liquid and conventional plasma chemical vapor deposition methods

    Science.gov (United States)

    Takahashi, Yoshiyuki; Toyota, Hiromichi; Nomura, Shinfuku; Mukasa, Shinobu; Inoue, Toru

    2009-06-01

    In order to make high-speed deposition of diamond effective, diamond growth rates for gas-phase microwave plasma chemical vapor deposition and in-liquid microwave plasma chemical vapor deposition are compared. A mixed gas of methane and hydrogen is used as the source gas for the gas-phase deposition, and a methanol solution of ethanol is used as the source liquid for the in-liquid deposition. The experimental system pressure is in the range of 60-150 kPa. While the growth rate of diamond increases as the pressure increases, the amount of input microwave energy per unit volume of diamond is 1 kW h/mm3 regardless of the method used. Since the in-liquid deposition method provides a superior cooling effect through the evaporation of the liquid itself, a higher electric input power can be applied to the electrodes under higher pressure environments. The growth rate of in-liquid microwave plasma chemical vapor deposition process is found to be greater than conventional gas-phase microwave plasma chemical vapor deposition process under the same pressure conditions.

  7. Graphitization of diamond with a metallic coating on ferritic matrix; Grafitizacao do diamante com revestimento metalico em matriz ferritica

    Energy Technology Data Exchange (ETDEWEB)

    Cabral, Stenio Cavalier; Oliveira, Hellen Cristine Prata de; Filgueira, Marcello, E-mail: stenio@uenf.b [Universidade Estadual do Norte Fluminense (PPGECM/CCT/UENF), Campos dos Goytacazes, RJ (Brazil). Centro de Ciencias e Tecnologia. Programa de Pos Graduacao em Engenharia e Ciencia dos Materiais

    2010-07-01

    Iron is a strong catalyst of graphitization of diamonds. This graphitization occurs mainly during the processing of composites - conventional sintering or hot pressing, and during cutting operations. Aiming to avoid or minimize this deleterious effect, there is increasing use of diamond coated with metallic materials in the production of diamond tools processed via powder metallurgy. This work studies the influence of Fe on diamond graphitization diamond-coated Ti after mixing of Fe-diamonds, hot pressing parameters were performed with 3 minutes/35MPa/900 deg C - this is the condition of pressing hot used in industry for production of diamond tools. Microstructural features were observed by SEM, diffusion of Fe in diamond was studied by EDS. Graphitization was analyzed by X-ray diffraction and Raman spectroscopy. It was found that Fe not activate graphitization on the diamond under the conditions of hot pressing. (author)

  8. Temperature effect on the formation of a relief of diamond-like carbon coatings and its modification by ion bombardment

    International Nuclear Information System (INIS)

    Rubshtein, A.P.; Trakhtenberg, I.Sh.; Yugov, V.A.; Vladimirov, A.B.; Plotnikov, S.A.; Ponosov, Yu.S

    2006-01-01

    Using the method of pulsed arc sputtering of a graphite target the diamond-like coatings (DLC) ∼1.5 μm thick are deposited on a steel R6M5 substrate. The relief of the coatings obtained under various temperature conditions is investigated. Variations of carbon DLC surfaces are followed after their bombardment with accelerated argon or chemically active oxygen ions. Argon ion bombardment is established to be preferred for producing a smoothed-out DLC relief. It is shown that a DLC relief should be taken into account when measuring microhardness. It is recommended that transformation of interatomic bonds in irradiated subsurface layers be taken into consideration if information index of methods applied constitutes several monolayers [ru

  9. Total inorganic arsenic detection in real water samples using anodic stripping voltammetry and a gold-coated diamond thin-film electrode.

    Science.gov (United States)

    Song, Yang; Swain, Greg M

    2007-06-12

    An accurate method for total inorganic arsenic determination in real water samples was developed using differential pulse anodic stripping voltammetry (DPASV) and a Au-coated boron-doped diamond thin-film electrode. Keys to the method are the use of a conducting diamond platform and solid phase extraction for sample preparation. In the method, the As(III) present in the sample is first detected by DPASV. The As(V) present is then reduced to As(III) by reaction with Na2SO3 and this is followed by a second detection of As(III) by DPASV. Interfering metal ions (e.g., Cu(II)) that cause decreased electrode response sensitivity for arsenic in real samples are removed by solid phase extraction as part of the sample preparation. For example, Cu(II) caused a 30% decrease in the As stripping peak current at a solution concentration ratio of 3:1 (Cu(II)/As(III)). This loss was mitigated by passage of the solution through a Chelex 100 cation exchange resin. After passage, only a 5% As stripping current response loss was seen. The effect of organic matter on the Au-coated diamond electrode response for As(III) was also evaluated. Humic acid at a 5 ppm concentration caused only a 9% decrease in the As stripping peak charge for Au-coated diamond. By comparison, a 50% response decrease was observed for Au foil. Clearly, the chemical properties of the diamond surface in the vicinity of the metal deposits inhibit molecular adsorption on at least some of the Au surface. The method provided reproducible and accurate results for total inorganic arsenic in two contaminated water samples provided by the U.S. Bureau of Reclamation. The total inorganic As concentration in the two samples, quantified by the standard addition method, was 23.2+/-2.9 ppb for UV plant influent water and 16.4+/-0.9 ppb for Well 119 water (n=4). These values differed from the specified concentrations by less than 4%.

  10. Total inorganic arsenic detection in real water samples using anodic stripping voltammetry and a gold-coated diamond thin-film electrode

    International Nuclear Information System (INIS)

    Song Yang; Swain, Greg M.

    2007-01-01

    An accurate method for total inorganic arsenic determination in real water samples was developed using differential pulse anodic stripping voltammetry (DPASV) and a Au-coated boron-doped diamond thin-film electrode. Keys to the method are the use of a conducting diamond platform and solid phase extraction for sample preparation. In the method, the As(III) present in the sample is first detected by DPASV. The As(V) present is then reduced to As(III) by reaction with Na 2 SO 3 and this is followed by a second detection of As(III) by DPASV. Interfering metal ions (e.g., Cu(II)) that cause decreased electrode response sensitivity for arsenic in real samples are removed by solid phase extraction as part of the sample preparation. For example, Cu(II) caused a 30% decrease in the As stripping peak current at a solution concentration ratio of 3:1 (Cu(II)/As(III)). This loss was mitigated by passage of the solution through a Chelex 100 cation exchange resin. After passage, only a 5% As stripping current response loss was seen. The effect of organic matter on the Au-coated diamond electrode response for As(III) was also evaluated. Humic acid at a 5 ppm concentration caused only a 9% decrease in the As stripping peak charge for Au-coated diamond. By comparison, a 50% response decrease was observed for Au foil. Clearly, the chemical properties of the diamond surface in the vicinity of the metal deposits inhibit molecular adsorption on at least some of the Au surface. The method provided reproducible and accurate results for total inorganic arsenic in two contaminated water samples provided by the U.S. Bureau of Reclamation. The total inorganic As concentration in the two samples, quantified by the standard addition method, was 23.2 ± 2.9 ppb for UV plant influent water and 16.4 ± 0.9 ppb for Well 119 water (n = 4). These values differed from the specified concentrations by less than 4%

  11. Applications of diamond films and related materials; Proceedings of the 1st International Conference, Auburn, AL, Aug. 17-22, 1991

    Science.gov (United States)

    Tzeng, Yonhua (Editor); Yoshikawa, Manasori (Editor); Murakawa, Masao (Editor); Feldman, Albert (Editor)

    1991-01-01

    The present conference discusses the nucleation and growth of diamond from hydrocarbons, the cutting tool performance of CVD thick-film diamond, the characterization of CVD diamond grinding powder, industrial applications of crystalline diamond-coated tools, standardized SEM tribometry of diamond-coated substrates, residual stress in CVD diamond films, the optical properties of CVD diamond films, polycrystalline diamond films for optical applications, and diamond growth on ferrous metals. Also discussed are ion beam-irradiation smoothing of diamond films, electronic circuits on diamond substrates, diamond-laminated surfaces for evaporative spray cooling, electron devices based on the unique properties of diamond, diamond cold cathodes, thin-film diamond microstructure applications, Schottky diodes from flame-grown diamond, diamond films for thermionic applications, methods of diamond nucleation and selective deposition, high-rate/large-area diamond film production, halogen-assisted diamond growth, the economics of diamond technology, and the optical and mechanical properties of diamondlike films.

  12. Diamond synthesis at atmospheric pressure by microwave capillary plasma chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Hemawan, Kadek W.; Gou, Huiyang; Hemley, Russell J. [Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Rd., NW, Washington, DC 20015 (United States)

    2015-11-02

    Polycrystalline diamond has been synthesized on silicon substrates at atmospheric pressure, using a microwave capillary plasma chemical vapor deposition technique. The CH{sub 4}/Ar plasma was generated inside of quartz capillary tubes using 2.45 GHz microwave excitation without adding H{sub 2} into the deposition gas chemistry. Electronically excited species of CN, C{sub 2}, Ar, N{sub 2}, CH, H{sub β}, and H{sub α} were observed in the emission spectra. Raman measurements of deposited material indicate the formation of well-crystallized diamond, as evidenced by the sharp T{sub 2g} phonon at 1333 cm{sup −1} peak relative to the Raman features of graphitic carbon. Field emission scanning electron microscopy images reveal that, depending on the growth conditions, the carbon microstructures of grown films exhibit “coral” and “cauliflower-like” morphologies or well-facetted diamond crystals with grain sizes ranging from 100 nm to 10 μm.

  13. Diamond growth in oxygen-acetylene flame

    International Nuclear Information System (INIS)

    Haga, Mario S.; Nagai, Y. Ernesto; Suzuki, Carlos K.

    1995-01-01

    What was supposed to be a laboratory curiosity in the 80's, in recent years the low pressure process for the production of man-made diamond turned out to be a major target for research and development of many high-tech companies. The main reason for such an interest stems on the possibility of coating many materials with a diamond film possessing the same amazing properties of the bulk natural diamond. Polycrystalline diamond film has been deposited on Mo substrate by using oxygen-acetylene flame of a welding torch. The substrate temperature has been held constant about 700 d eg C by means of a water cooled mount designed properly. Precision flowmeters have been used to control the flow ratio oxygen/acetylene, a key parameter for the success in diamond growth. Diamond has been detected by X-ray diffraction, a fast foolproof technique for crystal identification. Another method of analysis often used in Raman spectroscopy, which is able to exhibit amorphous structure besides crystalline phase. (author)

  14. Method for producing fluorinated diamond-like carbon films

    Science.gov (United States)

    Hakovirta, Marko J.; Nastasi, Michael A.; Lee, Deok-Hyung; He, Xiao-Ming

    2003-06-03

    Fluorinated, diamond-like carbon (F-DLC) films are produced by a pulsed, glow-discharge plasma immersion ion processing procedure. The pulsed, glow-discharge plasma was generated at a pressure of 1 Pa from an acetylene (C.sub.2 H.sub.2) and hexafluoroethane (C.sub.2 F.sub.6) gas mixture, and the fluorinated, diamond-like carbon films were deposited on silicon substrates. The film hardness and wear resistance were found to be strongly dependent on the fluorine content incorporated into the coatings. The hardness of the F-DLC films was found to decrease considerably when the fluorine content in the coatings reached about 20%. The contact angle of water on the F-DLC coatings was found to increase with increasing film fluorine content and to saturate at a level characteristic of polytetrafluoroethylene.

  15. Adherent diamond coatings on cemented tungsten carbide substrates with new Fe/Ni/Co binder phase

    International Nuclear Information System (INIS)

    Polini, Riccardo; Delogu, Michele; Marcheselli, Giancarlo

    2006-01-01

    WC-Co hard metals continue to gain importance for cutting, mining and chipless forming tools. Cobalt metal currently dominates the market as a binder because of its unique properties. However, the use of cobalt as a binder has several drawbacks related to its hexagonal close-packed structure and market price fluctuations. These issues pushed the development of pre-alloyed binder powders which contain less than 40 wt.% cobalt. In this paper we first report the results of extensive investigations of WC-Fe/Ni/Co hard metal sintering, surface pretreating and deposition of adherent diamond films by using an industrial hot filament chemical vapour deposition (HFCVD) reactor. In particular, CVD diamond was deposited onto WC-Fe/Ni/Co grades which exhibited the best mechanical properties. Prior to deposition, the substrates were submitted to surface roughening by Murakami's etching and to surface binder removal by aqua regia. The adhesion was evaluated by Rockwell indentation tests (20, 40, 60 and 100 kg) conducted with a Brale indenter and compared to the adhesion of diamond films grown onto Co-cemented tungsten carbide substrates, which were submitted to similar etching pretreatments and identical deposition conditions. The results showed that diamond films on medium-grained WC-6 wt.% Fe/Ni/Co substrates exhibited good adhesion levels, comparable to those obtained for HFCVD diamond on Co-cemented carbides with similar microstructure

  16. Study on tribological behavior and cutting performance of CVD diamond and DLC films on Co-cemented tungsten carbide substrates

    International Nuclear Information System (INIS)

    Zhang Dongcan; Shen Bin; Sun Fanghong

    2010-01-01

    The tribological behaviors of diamond and diamond-like carbon (DLC) films play a major role on their machining and mechanical applications. In this study, diamond and diamond-like carbon (DLC) films are deposited on the cobalt cemented tungsten carbide (WC-Co) substrate respectively adopting the hot filament chemical vapor deposition (HFCVD) technique and the vacuum arc discharge with a graphite cathode, and their friction properties are evaluated on a reciprocating ball-on-plate tribometer with counterfaces of silicon nitride (Si 3 N 4 ) ceramic, cemented tungsten carbide (WC) and ball-bearing steel materials, under the ambient air without lubricating condition. Moreover, to evaluate their cutting performance, comparative turning tests are conducted using the uncoated WC-Co and as-fabricated CVD diamond and DLC coated inserts, with glass fiber reinforced plastics (GFRP) composite materials as the workpiece. The as-deposited HFCVD diamond and DLC films are characterized with energy-dispersive X-ray spectroscopy (EDX), scanning electron microscope (SEM), X-ray diffraction spectroscopy (XRD), Raman spectroscopy and 3D surface topography based on white-light interferometry. Furthermore, Rocwell C indentation tests are conducted to evaluate the adhesion of HFCVD diamond and DLC films grown onto WC-Co substrates. SEM and 3D surface topography based on white-light interferometry are also used to investigate the worn region on the surfaces of diamond and DLC films. The friction tests suggest that the obtained friction coefficient curves that of various contacts exhibit similar evolution tendency. For a given counterface, DLC films present lower stable friction coefficients than HFCVD diamond films under the same sliding conditions. The cutting tests results indicate that flank wear of the HFCVD diamond coated insert is lower than that of DLC coated insert before diamond films peeling off.

  17. Electrochemical deposition of mineralized BSA/collagen coating

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang, Junjun [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); Lin, Jun; Li, Juan; Wang, Huiming [The First Affiliated Hospital of Medical College, Zhejiang University, Hangzhou 310003 (China); Cheng, Kui [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); Weng, Wenjian, E-mail: wengwj@zju.edu.cn [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); The Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China)

    2016-09-01

    In this work, mineralized collagen coatings with different loading quantity of bovine serum albumin (BSA) were prepared via in situ electrochemical deposition on titanium substrate. The microstructure and BSA loading quantity of the coatings could be controlled by the electrochemical deposition parameters, such as deposition potential, BSA concentration and its adding sequence in the electrolyte. The BSA loading quantity in the coatings was obtained in the range of 0.0170–0.173 mg/cm{sup 2}, enhancing the cell adhesion and proliferation of the coatings with the simultaneous release. The distinct release behaviors of BSA were attributed to their gradient distribution with different mineralization degrees, which could be adjusted by the deposition process. These results suggest that in situ electrochemical deposition is a promising way to incorporate functional molecules into the mineralized collagen coatings and the mineralized BSA/collagen coatings are highly promising for improving the rhBMP-2 loading capability (1.8-fold). - Highlights: • BSA is incorporated into mineralized collagen coating by electrochemical deposition. • The loading amount of BSA in coatings can be adjusted in the range of 0-173 ng. • The BSA/collagen coating shows good cytocompatibility with free-albumin culture. • The incorporation process is put forward for some other molecules deposition.

  18. Measurement of the Fermi potential of diamond-like carbon and other materials

    International Nuclear Information System (INIS)

    Atchison, F.; Blau, B.; Daum, M.; Fierlinger, P.; Geltenbort, P.; Gupta, M.; Henneck, R.; Heule, S.; Kasprzak, M.; Knecht, A.; Kuzniak, M.; Kirch, K.; Meier, M.; Pichlmaier, A.; Reiser, R.; Theiler, B.; Zimmer, O.; Zsigmond, G.

    2007-01-01

    The Fermi potential V f of diamond-like carbon (DLC) coatings produced with laser-controlled vacuum arc deposition and that of diamond, Al, Si, Be, Cu, Fe and Ni was measured using two different methods, (i) transmission of slow neutrons through foils in a time-of-flight experiment and (ii) cold neutron reflectometry (CNR). For diamond-like carbon in transmission we obtain V f = (249 ± 14) neV. This is approximately the same as for beryllium and consistent with the theoretical expectations for the measured diamond (sp 3 ) content of 45%. For an sp 3 -content of 67%, we find V f (271 ± 13) neV from reflectometry, again in agreement with theory. These findings open new perspectives in using DLC as storage volume and neutron guide coatings for ultracold neutron sources

  19. Interlayers Applied to CVD Diamond Deposition on Steel Substrate: A Review

    Directory of Open Access Journals (Sweden)

    Djoille Denner Damm

    2017-09-01

    Full Text Available Academics and industry have sought after combining the exceptional properties of diamonds with the toughness of steel. Since the early 1990s several partial solutions have been found but chemical vapor deposition (CVD diamond deposition on steel substrate continues to be a persistent problem. The main drawbacks are the high carbon diffusion from gas phase into substrate, the transition metals on the material surface that catalyze sp2 bond formation, instead of sp3 bonds, and the high thermal expansion coefficient (TEC mismatch between diamond and steels. An intermediate layer has been found necessary to increase diamond adhesion. Literature has proposed many efficient intermediate layers as a diffusion barrier for both, carbon and iron, but most intermediate layers shown have not solved TEC mismatch. In this review, we briefly discuss the solutions that exclusively work as diffusion barrier and discuss in a broader way the ones that also solve, or may potentially solve, the TEC mismatch problem. We examine some multilayers, the iron borides, the chromium carbides, and vanadium carbides. We go through the most relevant results of the last two and a half decades, including recent advances in our group. Vanadium carbide looks promising since it has shown excellent diffusion barrier properties, its TEC is intermediary between diamond and steel and, it has been thickened to manage thermal stress relief. We also review a new deposition technique to set up intermediate layers: laser cladding. It is promising because of its versatility in mixing different materials and fusing and/or sintering them on a steel surface. We conclude by remarking on new perspectives.

  20. Development of Single Crystal Chemical Vapor Deposition Diamonds for Detector Applications

    International Nuclear Information System (INIS)

    Kagan, Harris; Gan, K.K.; Kass, Richard

    2009-01-01

    Diamond was studied as a possible radiation hard technology for use in future high radiation environments. With the commissioning of the LHC expected in 2009, and the LHC upgrades expected in 2013, all LHC experiments are planning for detector upgrades which require radiation hard technologies. Chemical Vapor Deposition (CVD) diamond has now been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle and CDF and is installed in all LHC experiments. As a result, this material is now being discussed as an alternative sensor material for tracking very close to the interaction region of the super-LHC where the most extreme radiation conditions will exist. Our work addressed the further development of the new material, single-crystal Chemical Vapor Deposition diamond, towards reliable industrial production of large pieces and new geometries needed for detector applications.

  1. Chromium-doped diamond-like carbon films deposited by dual-pulsed laser deposition

    Czech Academy of Sciences Publication Activity Database

    Písařík, Petr; Jelínek, Miroslav; Kocourek, Tomáš; Zezulová, M.; Remsa, Jan; Jurek, Karel

    2014-01-01

    Roč. 117, č. 1 (2014), s. 83-88 ISSN 0947-8396 R&D Projects: GA MŠk LD12069 Institutional support: RVO:68378271 Keywords : diamond like carbon * chromium * contact angle * surface free energy * dual laser deposition * zeta potential Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.704, year: 2014

  2. Simulation optimization of filament parameters for uniform depositions of diamond films on surfaces of ultra-large circular holes

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xinchang, E-mail: wangxinchangz@163.com; Shen, Xiaotian; Sun, Fanghong; Shen, Bin

    2016-12-01

    Highlights: • A verified simulation model using a novel filament arrangement is constructed. • Influences of filament parameters are clarified. • A coefficient between simulated and experimental results is proposed. • Orthogonal simulations are adopted to optimize filament parameters. • A general filament arrangement suitable for different conditions is determined. - Abstract: Chemical vapor deposition (CVD) diamond films have been widely applied as protective coatings on varieties of anti-frictional and wear-resistant components, owing to their excellent mechanical and tribological properties close to the natural diamond. In applications of some components, the inner hole surface will serve as the working surface that suffers severe frictional or erosive wear. It is difficult to realize uniform depositions of diamond films on surfaces of inner holes, especially ultra-large inner holes. Adopting a SiC compact die with an aperture of 80 mm as an example, a novel filament arrangement with a certain number of filaments evenly distributed on a circle is designed, and specific effects of filament parameters, including the filament number, arrangement direction, filament temperature, filament diameter, circumradius and the downward translation, on the substrate temperature distribution are studied by computational fluid dynamics (CFD) simulations based on the finite volume method (FVM), adopting a modified computational model well consistent with the actual deposition environment. Corresponding temperature measurement experiments are also conducted to verify the rationality of the computational model. From the aspect of depositing uniform boron-doped micro-crystalline, undoped micro-crystalline and undoped fine-grained composite diamond (BDM-UMC-UFGCD) film on such the inner hole surface, filament parameters as mentioned above are accurately optimized and compensated by orthogonal simulations. Moreover, deposition experiments adopting compensated optimized

  3. Development of a new neutron mirror made of deuterated Diamond-like carbon

    International Nuclear Information System (INIS)

    Sakurai, Dai; Chiba, Junsei; Shimizu, Hirohiko M; Nishimura, Daiki; Ino, Takashi; Kaneko, Naokatsu; Muto, Suguru; Kakusho, Nobunori; Seki, Yoshichika; Katayama, Ryo; Kitaguchi, Masaaki; Mishima, Kenji; Yamashita, Satoru; Ozeki, Kazuhide; Yoshioka, Tamaki

    2014-01-01

    We developed a new neutron mirror made of Diamond-like carbon (DLC). DLC is a film of amorphous carbon that has characteristics of both diamond and graphite. We produced DLC mirrors by ionization deposition method which is one of the chemical vapor deposition (CVD). Generally, DLC made by CVD contents a few tens of percentages of hydrogen. It decreases the Fermi potential of the DLC coating because hydrogen has negative Fermi potential. In order to increase the Fermi potential of the coating, we deuterated the DLC by using deuterated benzene for the source gas. The characteristics of the deuterated DLC(DDLC) coating was evaluated by RBS, ERDA, x-ray reflectivity, AFM. As a result, DDLC coating has 243 neV due to deuteration, which is the same level as Ni. The RMS of height of the DDLC was 0.6nm so that the DDLC coating can be applied for a focusing mirror or specular transportation of pulsed neutron. Besides, we also develop Hydrogen/Deuterium DLC multiple layer mirror. So far, 4 layers mirror has been succeeded.

  4. Studies of internal stress in diamond films prepared by DC plasma chemical vapour deposition

    International Nuclear Information System (INIS)

    Wang Wanlu; Gao Jinying; Liao Kejun; Liu Anmin

    1992-01-01

    The internal stress in diamond thin films deposited by DC plasma CVD was studied as a function of methane concentration and deposited temperature. Experimental results have shown that total stress in diamond thin films is sensitive to the deposition conditions. The results also indicate that the compressive stress can be explained in terms of amorphous state carbon and hydrogen, and tensile stress is ascribed to the grain boundary relaxation model due to high internal surface area and microstructure with voids

  5. In vitro and in vivo investigations into the biocompatibility of diamond-like carbon (DLC) coatings for orthopedic applications.

    Science.gov (United States)

    Allen, M; Myer, B; Rushton, N

    2001-05-01

    Diamond-like carbon (DLC) shows great promise as a durable, wear- and corrosion-resistant coating for biomedical implants. The effects of DLC coatings on the musculoskeletal system have not been investigated in detail. In this study, DLC coatings were deposited on polystyrene 24-well tissue culture plates by fast-atom bombardment from a hexane precursor. Two osteoblast-like cell lines were cultured on uncoated and DLC-coated plates for periods of up to 72 h. The effects of DLC coatings on cellular metabolism were investigated by measuring the production of three osteoblast-specific marker proteins: alkaline phosphatase, osteocalcin, and type I collagen. There was no evidence that the presence of the DLC coating had any adverse effect on any of the parameters measured in this study. In a second series of experiments, DLC-coated cobalt-chromium cylinders were implanted in intramuscular locations in rats and in transcortical sites in sheep. Histologic analysis of specimens retrieved 90 days after surgery showed that the DLC-coated specimens were well tolerated in both sites. These data indicate that DLC coatings are biocompatible in vitro and in vivo, and further investigations into their long-term biological and tribological performance are now warranted. Copyright 2001 John Wiley & Sons, Inc.

  6. Polycrystalline diamond on self-assembled detonation nanodiamond: a viable route for fabrication of all-diamond preformed microcomponents

    International Nuclear Information System (INIS)

    Terranova, M L; Orlanducci, S; Tamburri, E; Guglielmotti, V; Toschi, F; Hampai, D; Rossi, M

    2008-01-01

    Surface assisted self-assembly of detonation nanodiamond particles (with typical sizes in the range 4-10 nm) has been obtained using different fractions of colloidal aqueous dispersions as starting material. The relationship between dispersion properties and structure/geometry of the aggregates deposited on Si or glass plates has been investigated. A series of differently shaped free-standing nanodiamond structures has been prepared, analysed and used as templates for the growth of polycrystalline diamond layers by the chemical vapour deposition (CVD) technique. The possibility of obtaining textured coating with a relatively strong preferred orientation (within a solid angle of about 0.6 srad) is also reported. Overall, the coupling of nanodiamond self-assembling to the CVD diamond growth enables one to produce specimens with complex 3D architectures. The proposed microfabrication methodology could represent a viable route for the production of free-standing all-diamond microcomponents, with tailored shapes and predefined crystalline features, to be used for advanced electronic applications

  7. Polycrystalline diamond on self-assembled detonation nanodiamond: a viable route for fabrication of all-diamond preformed microcomponents

    Energy Technology Data Exchange (ETDEWEB)

    Terranova, M L; Orlanducci, S; Tamburri, E; Guglielmotti, V; Toschi, F [Dipartimento di Scienze e Tecnologie Chimiche, MINASlab, Universita di Roma ' Tor Vergata' , Via della Ricerca Scientifica, 00133 Roma (Italy); Hampai, D [INFN-LNF Via E Fermi 40, Frascati (Italy); Rossi, M [Dipartimento di Energetica, Universita di Roma ' Sapienza' , Via Antonio Scarpa 16, 00161 Roma (Italy)

    2008-10-15

    Surface assisted self-assembly of detonation nanodiamond particles (with typical sizes in the range 4-10 nm) has been obtained using different fractions of colloidal aqueous dispersions as starting material. The relationship between dispersion properties and structure/geometry of the aggregates deposited on Si or glass plates has been investigated. A series of differently shaped free-standing nanodiamond structures has been prepared, analysed and used as templates for the growth of polycrystalline diamond layers by the chemical vapour deposition (CVD) technique. The possibility of obtaining textured coating with a relatively strong <110> preferred orientation (within a solid angle of about 0.6 srad) is also reported. Overall, the coupling of nanodiamond self-assembling to the CVD diamond growth enables one to produce specimens with complex 3D architectures. The proposed microfabrication methodology could represent a viable route for the production of free-standing all-diamond microcomponents, with tailored shapes and predefined crystalline features, to be used for advanced electronic applications.

  8. Diamond MEMS: wafer scale processing, devices, and technology insertion

    Science.gov (United States)

    Carlisle, J. A.

    2009-05-01

    Diamond has long held the promise of revolutionary new devices: impervious chemical barriers, smooth and reliable microscopic machines, and tough mechanical tools. Yet it's been an outsider. Laboratories have been effectively growing diamond crystals for at least 25 years, but the jump to market viability has always been blocked by the expense of diamond production and inability to integrate with other materials. Advances in chemical vapor deposition (CVD) processes have given rise to a hierarchy of carbon films ranging from diamond-like carbon (DLC) to vapor-deposited diamond coatings, however. All have pros and cons based on structure and cost, but they all share some of diamond's heralded attributes. The best performer, in theory, is the purest form of diamond film possible, one absent of graphitic phases. Such a material would capture the extreme hardness, high Young's modulus and chemical inertness of natural diamond. Advanced Diamond Technologies Inc., Romeoville, Ill., is the first company to develop a distinct chemical process to create a marketable phase-pure diamond film. The material, called UNCD® (for ultrananocrystalline diamond), features grain sizes from 3 to 300 nm in size, and layers just 1 to 2 microns thick. With significant advantages over other thin films, UNCD is designed to be inexpensive enough for use in atomic force microscopy (AFM) probes, microelectromechanical machines (MEMS), cell phone circuitry, radio frequency devices, and even biosensors.

  9. Comparative assessment of the microhardness and plastic degradation mechanism of deposited modulated coatings on mild steel

    Science.gov (United States)

    Fayomi, O. S. I.; Anawe, P. A. L.; Inegbenebor, A. O.; Udoye, N. E.

    2018-05-01

    Zinc based coatings modified with aluminium and tin inclusions were electrodeposited in chloride zinc sulfate electrolytes containing a metallic powder of titanium. It was found that presence of these particulates is suitable to obtain ZnAlSn-Ti composites coating that could help increase the microhardnesss characteristics and wear properties. The hardness and wear properties of the deposited coatings were examined with diamond base micro-hardness tester and CETR reciprocating sliding tester respectively. The structural properties were examined with the help of scanning electron microscope. It was observed that structural coating surface impact on the hardness propagation with increases from 33.4 to 299 kgf mm-2 (HVN40), and shows a considerably higher wear resistance from 2.351g/min to 0.002g/min. It is obvious that plastic deformation of the working steel structure is dependent on protective coating and the concentration of the individual particulate.

  10. Magnetic and cytotoxic properties of hot-filament chemical vapour deposited diamond

    Energy Technology Data Exchange (ETDEWEB)

    Zanin, Hudson, E-mail: hudsonzanin@gmail.com [Faculdade de Engenharia Eletrica e Computacao, Departamento de Semicondutores, Instrumentos e Fotonica, Universidade Estadual de Campinas, UNICAMP, Av. Albert Einstein N.400, CEP 13 083-852 Campinas, Sao Paulo (Brazil); Peterlevitz, Alfredo Carlos; Ceragioli, Helder Jose [Faculdade de Engenharia Eletrica e Computacao, Departamento de Semicondutores, Instrumentos e Fotonica, Universidade Estadual de Campinas, UNICAMP, Av. Albert Einstein N.400, CEP 13 083-852 Campinas, Sao Paulo (Brazil); Rodrigues, Ana Amelia; Belangero, William Dias [Laboratorio de Biomateriais em Ortopedia, Faculdade de Ciencias Medicas, Universidade Estadual de Campinas, Rua Cinco de Junho 350 CEP 13083970, Campinas, Sao Paulo (Brazil); Baranauskas, Vitor [Faculdade de Engenharia Eletrica e Computacao, Departamento de Semicondutores, Instrumentos e Fotonica, Universidade Estadual de Campinas, UNICAMP, Av. Albert Einstein N.400, CEP 13 083-852 Campinas, Sao Paulo (Brazil)

    2012-12-01

    Microcrystalline (MCD) and nanocrystalline (NCD) magnetic diamond samples were produced by hot-filament chemical vapour deposition (HFCVD) on AISI 316 substrates. Energy Dispersive X-ray Spectroscopy (EDS) measurements indicated the presence of Fe, Cr and Ni in the MCD and NCD samples, and all samples showed similar magnetisation properties. Cell viability tests were realised using Vero cells, a type of fibroblastic cell line. Polystyrene was used as a negative control for toxicity (NCT). The cells were cultured under standard cell culture conditions. The proliferation indicated that these magnetic diamond samples were not cytotoxic. - Highlights: Black-Right-Pointing-Pointer Polycrystalline diamonds doped with Fe, Cr and Ni acquire ferromagnetic properties. Black-Right-Pointing-Pointer CVD diamonds have been prepared with magnetic and semiconductor properties. Black-Right-Pointing-Pointer Micro/nanocrystalline diamonds show good cell viability with fibroblast proliferation.

  11. Adherent diamond film deposited on Cu substrate by carbon transport from nanodiamond buried under Pt interlayer

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xuezhang [School of Materials Science and Engineering, Central South University, Changsha, 410083 (China); Wei Qiuping, E-mail: qiupwei@csu.edu.cn [School of Materials Science and Engineering, Central South University, Changsha, 410083 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha, 410083 (China); Yu Zhiming, E-mail: zhiming@csu.edu.cn [School of Materials Science and Engineering, Central South University, Changsha, 410083 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha, 410083 (China); Yang Taiming; Zhai Hao [School of Materials Science and Engineering, Central South University, Changsha, 410083 (China)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer Adherent polycrystalline diamond films were grown on copper substrate by carbon transport. Black-Right-Pointing-Pointer The nucleation density was increased to 10{sup 11} cm{sup -2}. Black-Right-Pointing-Pointer Diamond films were a composite structure of nano-crystalline diamond layer and micro-crystalline diamond layer. Black-Right-Pointing-Pointer Diamond nucleation was based by carbon dissolving from UDDs to Pt interlayer and formation of sp{sup 3}-bonded diamond clusters at the Pt surface. - Abstract: Diamond film deposited on Cu suffered from poor adhesion mainly due to the large mismatch of thermal expansion coefficients and the lack of affinity between carbon and Cu. Enhancing diamond nucleation by carbon transport from buried nanodiamond through a Pt ultrathin interlayer, adherent diamond film was then deposited on Cu substrate without distinctly metallic interlayer. This novel nucleation mechanism increased diamond nucleation density to 10{sup 11} cm{sup -2}, and developed diamond film with a composite structure of nano-crystalline diamond (NCD) layer and micro-crystalline diamond layer. Diamond film was characterized by the scanning electron microscope (SEM) and Raman spectroscope, respectively. The composition of diamond film/Cu substrate interface was examined by electron probe microanalysis (EPMA). The adhesion of diamond film was evaluated by indentation test. Those results show that a Pt ultrathin interlayer provides stronger chemically bonded interfaces and improve film adhesion.

  12. Adherent diamond film deposited on Cu substrate by carbon transport from nanodiamond buried under Pt interlayer

    International Nuclear Information System (INIS)

    Liu Xuezhang; Wei Qiuping; Yu Zhiming; Yang Taiming; Zhai Hao

    2013-01-01

    Highlights: ► Adherent polycrystalline diamond films were grown on copper substrate by carbon transport. ► The nucleation density was increased to 10 11 cm −2 . ► Diamond films were a composite structure of nano-crystalline diamond layer and micro-crystalline diamond layer. ► Diamond nucleation was based by carbon dissolving from UDDs to Pt interlayer and formation of sp 3 -bonded diamond clusters at the Pt surface. - Abstract: Diamond film deposited on Cu suffered from poor adhesion mainly due to the large mismatch of thermal expansion coefficients and the lack of affinity between carbon and Cu. Enhancing diamond nucleation by carbon transport from buried nanodiamond through a Pt ultrathin interlayer, adherent diamond film was then deposited on Cu substrate without distinctly metallic interlayer. This novel nucleation mechanism increased diamond nucleation density to 10 11 cm −2 , and developed diamond film with a composite structure of nano-crystalline diamond (NCD) layer and micro-crystalline diamond layer. Diamond film was characterized by the scanning electron microscope (SEM) and Raman spectroscope, respectively. The composition of diamond film/Cu substrate interface was examined by electron probe microanalysis (EPMA). The adhesion of diamond film was evaluated by indentation test. Those results show that a Pt ultrathin interlayer provides stronger chemically bonded interfaces and improve film adhesion.

  13. Biomedical applications of diamond-like carbon coatings: a review.

    Science.gov (United States)

    Roy, Ritwik Kumar; Lee, Kwang-Ryeol

    2007-10-01

    Owing to its superior tribological and mechanical properties with corrosion resistance, biocompatibility, and hemocompatibility, diamond-like carbon (DLC) has emerged as a promising material for biomedical applications. DLC films with various atomic bond structures and compositions are finding places in orthopedic, cardiovascular, and dental applications. Cells grew on to DLC coating without any cytotoxity and inflammation. DLC coatings in orthopedic applications reduced wear, corrosion, and debris formation. DLC coating also reduced thrombogenicity by minimizing the platelet adhesion and activation. However, some contradictory results (Airoldi et al., Am J Cardiol 2004;93:474-477, Taeger et al., Mat-wiss u Werkstofftech 2003;34:1094-1100) were also reported that no significant improvement was observed in the performance of DLC-coated stainless stent or DLC-coated femoral head. This controversy should be discussed based on the detailed information of the coating such as atomic bond structure, composition, and/or electronic structure. In addition, instability of the DLC coating caused by its high level of residual stress and poor adhesion in aqueous environment should be carefully considered. Further in vitro and in vivo studies are thus required to confirm its use for medical devices.

  14. Method for simultaneously coating a plurality of filaments

    Science.gov (United States)

    Miller, P.A.; Pochan, P.D.; Siegal, M.P.; Dominguez, F.

    1995-07-11

    Methods and apparatuses are disclosed for coating materials, and the products and compositions produced thereby. Substances, such as diamond or diamond-like carbon, are deposited onto materials, such as a filament or a plurality of filaments simultaneously, using one or more cylindrical, inductively coupled, resonator plasma reactors. 3 figs.

  15. INFLUENCE OF PLASMA NITRIDING ON THE CORROSION BEHAVIOUR AND ADHESION OF DLC COATINGS DEPOSITED ON AISI 420 STAINLESS STEEL

    Directory of Open Access Journals (Sweden)

    Jorge N. Pecina

    2016-06-01

    Full Text Available In this work the corrosion behavior and adhesion of two DLC (“Diamond Like Carbon” films (“Soft” and “Hard” were studied. Both coatings were deposited by PACVD (“Plasma Assisted Chemical Vapour Deposition” on plasma-nitrided and non-nitrided AISI 420 stainless steel. Raman spectroscopy was conducted and surface hardness was measured. The microstructure by OM and SEM, was observed. Adhesion tests were performed with C. Rockwell indentation test. Salt Spray and immersion were performed in HCl. The “Soft” coating was 20 μm thick, the “Hard” film was about 2.5 μm. The hardness was of 500 HV in the “Soft” DLC and 1400 HV in the “Hard” DLC. Both coatings presented low friction coefficient and good adhesion when they were deposited on nitrided steel. Also presented good resistance to atmospheric corrosion. HCl DLC degradation slowed rapidly introduced uncoated samples.

  16. AlTiN layer effect on mechanical properties of Ti-doped diamond-like carbon composite coatings

    International Nuclear Information System (INIS)

    Pang Xiaolu; Yang Huisheng; Gao Kewei; Wang Yanbin; Volinsky, Alex A.

    2011-01-01

    Ti/Ti-doped diamond-like carbon (DLC) and Ti/AlTiN/Ti-DLC composite coatings were deposited by magnetron sputtering on W18Cr4V high speed steel substrates. The effect of the AlTiN support layer on the properties of these composite coatings was investigated through microstructure and mechanical properties characterization, including hardness, elastic modulus, coefficient of friction and wear properties measured by scanning electron microscopy, Raman spectroscopy, scratch and ball-on-disk friction tests. Ti and AlTiN interlayers have a columnar structure with 50-80 nm grains. The hardness and elastic modulus of Ti/Ti-DLC and Ti/AlTiN/Ti-DLC coatings is 25.9 ± 0.4, 222.2 ± 6.3 GPa and 19.3 ± 1, 205.6 ± 6.7 GPa, respectively. Adhesion of Ti-DLC, Ti/AlTiN/Ti-DLC and AlTiN/Ti-DLC coatings expressed as the critical lateral force is 26.5 N, 38.2 N, and 47.8 N, respectively. Substrate coefficient of friction without coatings is 0.44, and it is 0.1 for Ti/Ti-DLC and Ti/AlTiN/Ti-DLC coatings. Wear resistance of Ti/AlTiN/Ti-DLC composite coatings is much higher than Ti/Ti-DLC coatings based on the wear track width of 169.8 and 73.2 μm, respectively, for the same experimental conditions.

  17. Transition Metal Ion Implantation into Diamond-Like Carbon Coatings: Development of a Base Material for Gas Sensing Applications

    Directory of Open Access Journals (Sweden)

    Andreas Markwitz

    2015-01-01

    Full Text Available Micrometre thick diamond-like carbon (DLC coatings produced by direct ion deposition were implanted with 30 keV Ar+ and transition metal ions in the lower percentage (<10 at.% range. Theoretical calculations showed that the ions are implanted just beneath the surface, which was confirmed with RBS measurements. Atomic force microscope scans revealed that the surface roughness increases when implanted with Ar+ and Cu+ ions, whereas a smoothing of the surface from 5.2 to 2.7 nm and a grain size reduction from 175 to 93 nm are measured for Ag+ implanted coatings with a fluence of 1.24×1016 at. cm−2. Calculated hydrogen and carbon depth profiles showed surprisingly significant changes in concentrations in the near-surface region of the DLC coatings, particularly when implanted with Ag+ ions. Hydrogen accumulates up to 32 at.% and the minimum of the carbon distribution is shifted towards the surface which may be the cause of the surface smoothing effect. The ion implantations caused an increase in electrical conductivity of the DLC coatings, which is important for the development of solid-state gas sensors based on DLC coatings.

  18. Microstructure of vapor deposited coatings on curved substrates

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, Theron M.; Zhao, Hengbei; Wadley, Haydn N. G., E-mail: haydn@virginia.edu [Department of Materials Science and Engineering, University of Virginia, 395 McCormick Rd., P.O. Box 400745, Charlottesville, Virginia 22904 (United States)

    2015-09-15

    Thermal barrier coating systems consisting of a metallic bond coat and ceramic over layer are widely used to extend the life of gas turbine engine components. They are applied using either high-vacuum physical vapor deposition techniques in which vapor atoms rarely experience scattering collisions during propagation to a substrate, or by gas jet assisted (low-vacuum) vapor deposition techniques that utilize scattering from streamlines to enable non-line-of-sight deposition. Both approaches require substrate motion to coat a substrate of complex shape. Here, direct simulation Monte Carlo and kinetic Monte Carlo simulation methods are combined to simulate the deposition of a nickel coating over the concave and convex surfaces of a model airfoil, and the simulation results are compared with those from experimental depositions. The simulation method successfully predicted variations in coating thickness, columnar growth angle, and porosity during both stationary and substrate rotated deposition. It was then used to investigate a wide range of vapor deposition conditions spanning high-vacuum physical vapor deposition to low-vacuum gas jet assisted vapor deposition. The average coating thickness was found to increase initially with gas pressure reaching a maximum at a chamber pressure of 8–10 Pa, but the best coating thickness uniformity was achieved under high vacuum deposition conditions. However, high vacuum conditions increased the variation in the coatings pore volume fraction over the surface of the airfoil. The simulation approach was combined with an optimization algorithm and used to investigate novel deposition concepts to tailor the local coating thickness.

  19. Microstructure of vapor deposited coatings on curved substrates

    International Nuclear Information System (INIS)

    Rodgers, Theron M.; Zhao, Hengbei; Wadley, Haydn N. G.

    2015-01-01

    Thermal barrier coating systems consisting of a metallic bond coat and ceramic over layer are widely used to extend the life of gas turbine engine components. They are applied using either high-vacuum physical vapor deposition techniques in which vapor atoms rarely experience scattering collisions during propagation to a substrate, or by gas jet assisted (low-vacuum) vapor deposition techniques that utilize scattering from streamlines to enable non-line-of-sight deposition. Both approaches require substrate motion to coat a substrate of complex shape. Here, direct simulation Monte Carlo and kinetic Monte Carlo simulation methods are combined to simulate the deposition of a nickel coating over the concave and convex surfaces of a model airfoil, and the simulation results are compared with those from experimental depositions. The simulation method successfully predicted variations in coating thickness, columnar growth angle, and porosity during both stationary and substrate rotated deposition. It was then used to investigate a wide range of vapor deposition conditions spanning high-vacuum physical vapor deposition to low-vacuum gas jet assisted vapor deposition. The average coating thickness was found to increase initially with gas pressure reaching a maximum at a chamber pressure of 8–10 Pa, but the best coating thickness uniformity was achieved under high vacuum deposition conditions. However, high vacuum conditions increased the variation in the coatings pore volume fraction over the surface of the airfoil. The simulation approach was combined with an optimization algorithm and used to investigate novel deposition concepts to tailor the local coating thickness

  20. The Influence of Chemical Alloying on the High Temperature Wear Resistance of H-Free DLC Coatings

    NARCIS (Netherlands)

    Galvan, D.; Pei, Y.T.; Hosson, J.T.M. De; Cavaleiro, A.; Chandra, T; Tsuzaki, K; Militzer, M; Ravindran, C

    2007-01-01

    A commercial RF-sputtering deposition rig was employed to deposit H-free diamond-like carbon (DLC) coatings. The influence of alloying elements such as Ti and Si on the structure, mechanical and tribological properties of the coatings was investigated. The coating was observed in cross section and

  1. Nanostructured Diamond-Like Carbon Films Grown by Off-Axis Pulsed Laser Deposition

    Directory of Open Access Journals (Sweden)

    Seong Shan Yap

    2015-01-01

    Full Text Available Nanostructured diamond-like carbon (DLC films instead of the ultrasmooth film were obtained by pulsed laser ablation of pyrolytic graphite. Deposition was performed at room temperature in vacuum with substrates placed at off-axis position. The configuration utilized high density plasma plume arriving at low effective angle for the formation of nanostructured DLC. Nanostructures with maximum size of 50 nm were deposited as compared to the ultrasmooth DLC films obtained in a conventional deposition. The Raman spectra of the films confirmed that the films were diamond-like/amorphous in nature. Although grown at an angle, ion energy of >35 eV was obtained at the off-axis position. This was proposed to be responsible for subplantation growth of sp3 hybridized carbon. The condensation of energetic clusters and oblique angle deposition correspondingly gave rise to the formation of nanostructured DLC in this study.

  2. Antithrombogenicity of Fluorinated Diamond-Like Carbon Films Coated Nano Porous Polyethersulfone (PES) Membrane

    Science.gov (United States)

    Prihandana, Gunawan S.; Sanada, Ippei; Ito, Hikaru; Noborisaka, Mayui; Kanno, Yoshihiko; Suzuki, Tetsuya; Miki, Norihisa

    2013-01-01

    A nano porous polyethersulfone (PES) membrane is widely used for aspects of nanofiltration, such as purification, fractionation and dialysis. However, the low-blood-compatibility characteristic of PES membrane causes platelets and blood cells to stick to the surface of the membrane and degrades ions diffusion through membrane, which further limits its application for dialysis systems. In this study, we deposited the fluorinated-diamond-like-carbon (F-DLC) onto the finger like structure layer of the PES membrane. By doing this, we have the F-DLC films coating the membrane surface without sacrificing the membrane permeability. In addition, we examined antithrombogenicity of the F-DLC/PES membranes using a microfluidic device, and experimentally found that F-DLC drastically reduced the amount of blood cells attached to the surface. We have also conducted long-term experiments for 24 days and the diffusion characteristics were found to be deteriorated due to fouling without any surface modification. On the other hand, the membranes coated by F-DLC film gave a consistent diffusion coefficient of ions transfer through a membrane porous. Therefore, F-DLC films can be a great candidate to improve the antithrombogenic characteristics of the membrane surfaces in hemodialysis systems. PMID:28788333

  3. Impact of the difference in power frequency on diamond-like carbon thin film coating over 3-dimensional objects

    Energy Technology Data Exchange (ETDEWEB)

    Nakaya, Masaki, E-mail: m-nakaya@kirin.co.jp [Packaging Technology Development Center, Technology Development Department, Kirin Brewery Co., Ltd., 1-17-1 Namamugi, Tsurumi-ku, Yokohama, Kanagawa 230-8682 (Japan); Shimizu, Mari [Packaging Technology Development Center, Technology Development Department, Kirin Brewery Co., Ltd., 1-17-1 Namamugi, Tsurumi-ku, Yokohama, Kanagawa 230-8682 (Japan); Uedono, Akira [Division of Applied Physics, Faculty of Pure and Applied Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan)

    2014-08-01

    With a type of capacitatively coupled plasma enhanced chemical vapor deposition (PECVD) technique, where two specially designed electrodes face to each other, the inner surface of hollow 3-dimensional objects such as poly(ethylene terephthalate) (PET) bottles can be coated with diamond-like carbon (DLC) thin film. DLC-coated PET bottles obtained with this technique have an enhanced gas barrier property, and therefore are applicable to industrial use such as for the extension of the shelf-life of contents sensitive to gas permeation. In this paper, the impact of power frequency ranging from 2.5 to 13.56 MHz was studied in order to research the behavior of plasma inside PET bottles and resultant properties. Different power frequency turned out to be influential on gas barrier property, the overall and distribution of tint, and adhesion between DLC and PET substrate. In addition, positron annihilation turned out to be powerful tool for the comparison of different coating conditions because it clarifies the homogeneity of DLC thin films through providing information on overall structure and thickness of them. These findings can be used for the optimization not only in the beverage PET bottle application, but also in other capacitatively coupled PECVD devices. - Highlights: • We demonstrated an effective methodology for the homogeneity of thin films. • We described the influence of power frequency on plasma and resultant thin film. • Diamond-like carbon coated on poly(ethylene terephthalate) bottles was used. • Different frequency provided homogenous thin films based on the above methodology. • For the industrial performance of the bottles, optimization was found at 6 MHz.

  4. Impact of the difference in power frequency on diamond-like carbon thin film coating over 3-dimensional objects

    International Nuclear Information System (INIS)

    Nakaya, Masaki; Shimizu, Mari; Uedono, Akira

    2014-01-01

    With a type of capacitatively coupled plasma enhanced chemical vapor deposition (PECVD) technique, where two specially designed electrodes face to each other, the inner surface of hollow 3-dimensional objects such as poly(ethylene terephthalate) (PET) bottles can be coated with diamond-like carbon (DLC) thin film. DLC-coated PET bottles obtained with this technique have an enhanced gas barrier property, and therefore are applicable to industrial use such as for the extension of the shelf-life of contents sensitive to gas permeation. In this paper, the impact of power frequency ranging from 2.5 to 13.56 MHz was studied in order to research the behavior of plasma inside PET bottles and resultant properties. Different power frequency turned out to be influential on gas barrier property, the overall and distribution of tint, and adhesion between DLC and PET substrate. In addition, positron annihilation turned out to be powerful tool for the comparison of different coating conditions because it clarifies the homogeneity of DLC thin films through providing information on overall structure and thickness of them. These findings can be used for the optimization not only in the beverage PET bottle application, but also in other capacitatively coupled PECVD devices. - Highlights: • We demonstrated an effective methodology for the homogeneity of thin films. • We described the influence of power frequency on plasma and resultant thin film. • Diamond-like carbon coated on poly(ethylene terephthalate) bottles was used. • Different frequency provided homogenous thin films based on the above methodology. • For the industrial performance of the bottles, optimization was found at 6 MHz

  5. Oxygen Barrier Coating Deposited by Novel Plasma-enhanced Chemical Vapor Deposition

    DEFF Research Database (Denmark)

    Jiang, Juan; Benter, M.; Taboryski, Rafael Jozef

    2010-01-01

    We report the use of a novel plasma-enhanced chemical vapor deposition chamber with coaxial electrode geometry for the SiOx deposition. This novel plasma setup exploits the diffusion of electrons through the inner most electrode to the interior samples space as the major energy source. This confi......We report the use of a novel plasma-enhanced chemical vapor deposition chamber with coaxial electrode geometry for the SiOx deposition. This novel plasma setup exploits the diffusion of electrons through the inner most electrode to the interior samples space as the major energy source...... effect of single-layer coatings deposited under different reaction conditions was studied. The coating thickness and the carbon content in the coatings were found to be the critical parameters for the barrier property. The novel barrier coating was applied on different polymeric materials...

  6. Deodorisation effect of diamond-like carbon/titanium dioxide multilayer thin films deposited onto polypropylene

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, K., E-mail: ozeki@mx.ibaraki.ac.jp [Department of Mechanical Engineering, Ibaraki University, 4-12-1, Nakanarusawa, Hitachi, Ibaraki 316-8511 (Japan); Frontier Research Center for Applied Atomic Sciences, 162-1 Shirakata, Toukai, Ibaraki 319-1106 (Japan); Hirakuri, K.K. [Applied Systems Engineering, Graduate School of Science and Engineering, Tokyo Denki University, Ishizaka, Hatoyama, Hiki, Saitama 350-0394 (Japan); Masuzawa, T. [Department of Mechanical Engineering, Ibaraki University, 4-12-1, Nakanarusawa, Hitachi, Ibaraki 316-8511 (Japan)

    2011-04-15

    Many types of plastic containers have been used for the storage of food. In the present study, diamond-like carbon (DLC)/titanium oxide (TiO{sub 2}) multilayer thin films were deposited on polypropylene (PP) to prevent flavour retention and to remove flavour in plastic containers. For the flavour removal test, two types of multilayer films were prepared, DLC/TiO{sub 2} films and DLC/TiO{sub 2}/DLC films. The residual gas concentration of acetaldehyde, ethylene, and turmeric compounds in bottle including the DLC/TiO{sub 2}-coated and the DLC/TiO{sub 2}/DLC-coated PP plates were measured after UV radiation, and the amount of adsorbed compounds to the plates was determined. The percentages of residual gas for acetaldehyde, ethylene, and turmeric with the DLC/TiO{sub 2} coated plates were 0.8%, 65.2% and 75.0% after 40 h of UV radiation, respectively. For the DLC/TiO{sub 2}/DLC film, the percentages of residual gas for acetaldehyde, ethylene and turmeric decreased to 34.9%, 76.0% and 85.3% after 40 h of UV radiation, respectively. The DLC/TiO{sub 2}/DLC film had a photocatalytic effect even though the TiO{sub 2} film was covered with the DLC film.

  7. Deodorisation effect of diamond-like carbon/titanium dioxide multilayer thin films deposited onto polypropylene

    International Nuclear Information System (INIS)

    Ozeki, K.; Hirakuri, K.K.; Masuzawa, T.

    2011-01-01

    Many types of plastic containers have been used for the storage of food. In the present study, diamond-like carbon (DLC)/titanium oxide (TiO 2 ) multilayer thin films were deposited on polypropylene (PP) to prevent flavour retention and to remove flavour in plastic containers. For the flavour removal test, two types of multilayer films were prepared, DLC/TiO 2 films and DLC/TiO 2 /DLC films. The residual gas concentration of acetaldehyde, ethylene, and turmeric compounds in bottle including the DLC/TiO 2 -coated and the DLC/TiO 2 /DLC-coated PP plates were measured after UV radiation, and the amount of adsorbed compounds to the plates was determined. The percentages of residual gas for acetaldehyde, ethylene, and turmeric with the DLC/TiO 2 coated plates were 0.8%, 65.2% and 75.0% after 40 h of UV radiation, respectively. For the DLC/TiO 2 /DLC film, the percentages of residual gas for acetaldehyde, ethylene and turmeric decreased to 34.9%, 76.0% and 85.3% after 40 h of UV radiation, respectively. The DLC/TiO 2 /DLC film had a photocatalytic effect even though the TiO 2 film was covered with the DLC film.

  8. Multilayer coatings containing diamond and other hard materials on hardmetal substrates

    International Nuclear Information System (INIS)

    Koepf, A.; Haubner, R.; Lux, B.

    2001-01-01

    In order to improve the wear resistance of hardmetal cutting tools, coatings of hard materials were established. Especially the production of multilayer coatings, which combine useful properties of different materials was a topic of industrial and academic research. The present work examined the possibilities of combining diamond as basic layer with protective CVD layers of TiC, TiN, Ti(C,N) and Al 2 O 3 . All these combinations could be realized and some showed quite good adherence under strain, which offers possibilities for technical applications. (author)

  9. Panel 1 - comparative evaluation of deposition technologies

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, G.R.; Stodolsky, F. [Argonne National Lab., IL (United States); Benson, D.K.; Pitts, R.J. [National Renewable Energy Lab., Golden, CO (United States); Bhat, D.G. [GTE Valenite Corp., Troy, MI (United States); Yulin Chen [Allison Gas Turbine Division, GM, Indianapolis, IN (United States); Gat, R.; Sunkara, M.K. [Case Western Reserve Univ., Cleveland, OH (United States); Kelly, M. [Stanford Univ., CA (United States); Lawler, J.E. [Univ. of Wisconsin, Madison (United States); Nagle, D.C. [Martin Marietta Labs., Baltimore, MD (United States); Outka, D. [Sandia National Laboratories, Livermore, CA (United States); Revankar, G.S. [Deere & Co., Moline, IL (United States); Subramaniam, V.V. [Ohio State Univ., Columbus (United States); Wilbur, P.J. [Colorado State Univ., Fort Collins (United States); Mingshow Wong [Northwestern Univ., Evanston, IL (United States); Woolam, W.E. [Southwest Research Inst., Arlington, VA (United States)

    1993-01-01

    This working group attempted to evaluate/compare the different types of deposition techniques currently under investigation for depositing diamond and diamond-like carbon films. A table lists the broad types of techniques that were considered for depositing diamond and diamond-like carbon films. After some discussion, it was agreed that any evaluation of the various techniques would be dependent on the end application. Thus the next action was to list the different areas where diamond and DLC films could find applications in transportation. These application areas are listed in a table. The table intentionally does not go into great detail on applications because that subject is dealt with specifically by Panel No. 4 - Applications To Transportation. The next action concentrated on identifying critical issues or limitations that need to be considered in evaluating the different processes. An attempt was then made to rank different broad categories of deposition techniques currently available or under development based on the four application areas and the limitations. These rankings/evaluations are given for diamond and DLC techniques. Finally, the working group tried to identify critical development and research issues that need to be incorporated into developing a long-term program that focuses on diamond/DLC coatings for transportation needs. 5 tabs.

  10. Vertically aligned carbon nanotubes/diamond double-layered structure for improved field electron emission stability

    Energy Technology Data Exchange (ETDEWEB)

    Yang, L., E-mail: qiaoqin.yang@mail.usask.ca; Yang, Q.; Zhang, C.; Li, Y.S.

    2013-12-31

    A double-layered nanostructure consisting of a layer of vertically aligned Carbon Nanotubes (CNTs) and a layer of diamond beneath has been synthesized on silicon substrate by Hot Filament Chemical Vapor Deposition. The synthesis was achieved by first depositing a layer of diamond on silicon and then depositing a top layer of vertically aligned CNTs by applying a negative bias on the substrate holder. The growth of CNTs was catalyzed by a thin layer of spin-coated iron nitride. The surface morphology and structure of the CNTs/diamond double-layered structure were characterized by Scanning Electron Microscope, Energy Dispersive X-ray spectrum, and Raman Spectroscopy. Their field electron emission (FEE) properties were measured by KEITHLEY 237 high voltage measurement unit, showing much higher FEE current stability than single layered CNTs. - Highlights: • A new double-layered nanostructure consisting of a layer of vertically aligned CNTs and a layer of diamond beneath has been synthesized by hot filament chemical vapor deposition. • This double-layered structure exhibits superior field electron emission stability. • The improvement of emission stability is due to the combination of the unique properties of diamond and CNTs.

  11. INFLUENCE OF THE SILICON INTERLAYER ON DIAMOND-LIKE CARBON FILMS DEPOSITED ON GLASS SUBSTRATES

    Directory of Open Access Journals (Sweden)

    Deiler Antonio Lima Oliveira

    2012-06-01

    Full Text Available Diamond-like carbon (DLC films as a hard protective coating have achieved great success in a diversity of technological applications. However, adhesion of DLC films to substrates can restrict their applications. The influence of a silicon interlayer in order to improve DLC adhesion on glass substrates was investigated. Amorphous silicon interlayer and DLC films were deposited using plasma enhanced chemical vapor deposition from silane and methane, respectively. The bonding structure, transmittance, refraction index, and adherence of the films were also evaluated regarding the thickness of the silicon interlayer. Raman scattering spectroscopy did not show any substantial difference in DLC structure due to the interlayer thickness of the silicon. Optical measurements showed a sharp decrease of transmittance in the ultra-violet region caused by the fundamental absorption of the light. In addition, the absorption edge of transmittance shifted toward longer wavelength side in the ultra-violet region as the thickness of the silicon interlayer increased. The tribological results showed an increase of DLC adherence as the silicon interlayer increased, which was characterized by less cracks around the grooves.

  12. Strain-induced ordered structure of titanium carbide during depositing diamond on Ti alloy substrate

    Energy Technology Data Exchange (ETDEWEB)

    Li, X.J., E-mail: lixj@alum.imr.ac.cn [College of Material Science and Engineering, Key Laboratory of Advanced Structural Materials, Ministry of Education, Changchun University of Technology, Changchun, 130012 (China); He, L.L., E-mail: llhe@imr.ac.cn [Shenyang National Lab of Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Li, Y.S. [Department of Mechanical Engineering, University of Saskatchewan, Saskatoon S7N 5A9, SK (Canada); Plasma Physics Laboratory, University of Saskatchewan, Saskatoon, SK S7N 5E2 (Canada); Yang, Q. [Department of Mechanical Engineering, University of Saskatchewan, Saskatoon S7N 5A9, SK (Canada); Hirose, A. [Plasma Physics Laboratory, University of Saskatchewan, Saskatoon, SK S7N 5E2 (Canada)

    2017-01-15

    During the deposition of diamond films on Ti alloy substrates, titanium carbide is a common precipitated phase, preferentially formed at the interfacial region. However, in this case, the precipitation of an ordered structure of titanium carbide has not been reported. In our work, a long periodic ordered structure of TiC has been observed at the deposited diamond film/Ti alloy interface by high resolution transmission electron microscopy (HRTEM). The long periodic ordered structure is identified as 6H-type. The formation mechanism is revealed by comparative studies on the different structures of TiC precipitated under different diamond deposition conditions in terms of deposition time, atmosphere and temperature. A large number of carbon vacancies in the interfacial precipitated TiC phase are verified through electron energy loss spectroscopy (EELS) quantification analysis. However, an ordered arrangement of these carbon vacancies occurs only when the interfacial stress is large enough to induce the precipitation of 6H-type TiC. The supplementary analysis by X-ray diffraction (XRD) further confirms that additional diffraction peaks presented in the XRD patterns are corresponding to the precipitation of 6H-type TiC. - Highlights: •Different structures of TiC are observed during deposited diamond on Ti alloy. •One is common NaCl structure, the other is periodic structure. •The periodic structure is identified as 6H-type by HRTEM. •Carbon vacancies are verified to always exist in the TiC phase. •The precipitation of 6H-type TiC is mainly affected by interfacial stress.

  13. Strain-induced ordered structure of titanium carbide during depositing diamond on Ti alloy substrate

    International Nuclear Information System (INIS)

    Li, X.J.; He, L.L.; Li, Y.S.; Yang, Q.; Hirose, A.

    2017-01-01

    During the deposition of diamond films on Ti alloy substrates, titanium carbide is a common precipitated phase, preferentially formed at the interfacial region. However, in this case, the precipitation of an ordered structure of titanium carbide has not been reported. In our work, a long periodic ordered structure of TiC has been observed at the deposited diamond film/Ti alloy interface by high resolution transmission electron microscopy (HRTEM). The long periodic ordered structure is identified as 6H-type. The formation mechanism is revealed by comparative studies on the different structures of TiC precipitated under different diamond deposition conditions in terms of deposition time, atmosphere and temperature. A large number of carbon vacancies in the interfacial precipitated TiC phase are verified through electron energy loss spectroscopy (EELS) quantification analysis. However, an ordered arrangement of these carbon vacancies occurs only when the interfacial stress is large enough to induce the precipitation of 6H-type TiC. The supplementary analysis by X-ray diffraction (XRD) further confirms that additional diffraction peaks presented in the XRD patterns are corresponding to the precipitation of 6H-type TiC. - Highlights: •Different structures of TiC are observed during deposited diamond on Ti alloy. •One is common NaCl structure, the other is periodic structure. •The periodic structure is identified as 6H-type by HRTEM. •Carbon vacancies are verified to always exist in the TiC phase. •The precipitation of 6H-type TiC is mainly affected by interfacial stress.

  14. Wear resistance of DLC coating deposited on pretreated AISI 4140 steel

    Energy Technology Data Exchange (ETDEWEB)

    Podgornik, B.; Vizintin, J. [Ljubljana Univ. (Slovenia). Centre of Tribology and Technical Diagnostics; Ronkainen, H.; Holmberg, K. [VTT Manufacturing Technology (Finland). Operational Reliability

    2000-07-01

    In the last few years, the application of nitrided steels as substrates for hard coatings has been increasingly reported. Diamond-like carbon (DLC) coatings, in particular, have attracted significant attention owing to their desirable tribological properties. The aim of the present study was to investigate the possibilities of using hard DLC coatings on softer substrates, such as AISI 4140 steel. (orig.)

  15. Diamond films on stainless steel substrates with an interlayer applied by laser cladding

    Energy Technology Data Exchange (ETDEWEB)

    Contin, Andre; Alves, Kenya Aparecida; Damm, Djoille Denner; Trava-Airoldi, Vladimir Jesus; Corat, Evaldo Jose, E-mail: andrecontin@yahoo.com.br [Instituto Nacional de Pesquisas Espaciais (LAS/INPE), Sao Jose dos Campos, SP (Brazil). Laboratorio Associado de Sensores e Materiais; Campos, Raonei Alves [Universidade Federal do Sul e Sudeste do Para (UNIFESSPA), Maraba, PA (Brazil); Vasconcelos, Getulio de [Instituto de Estudos Avancados (DedALO/IEAv), Sao Jose dos Campos, SP (Brazil). Laboratorio de Desenvolvimento de Aplicacoes de Lasers e Optica

    2017-03-15

    The objective of this work is the Hot Filament Chemical Vapor Deposition (HFCVD) of diamond films on stainless steel substrates using a new technique for intermediate barrier forming, made by laser cladding process. In this technique, a powder layer is irradiated by a laser beam to melt the powder layer and the substrate surface layer to create the interlayer. The control of the laser beam parameters allows creating homogeneous coating layers, in rather large area in few seconds. In this work, the silicon carbide powder (SiC) was used to create an intermediate layer. Before the diamond growth, the samples were subjected to the seeding process with diamond powder. The diamond deposition was performed using Hot-Filament CVD reactor and the characterizations were Scanning Electron Microscopy, X-ray diffraction, Raman Scattering Spectroscopy and Scratch Test. (author)

  16. Diamond-based materials for biomedical applications

    CERN Document Server

    Narayan, Roger

    2013-01-01

    Carbon is light-weight, strong, conductive and able to mimic natural materials within the body, making it ideal for many uses within biomedicine. Consequently a great deal of research and funding is being put into this interesting material with a view to increasing the variety of medical applications for which it is suitable. Diamond-based materials for biomedical applications presents readers with the fundamental principles and novel applications of this versatile material. Part one provides a clear introduction to diamond based materials for medical applications. Functionalization of diamond particles and surfaces is discussed, followed by biotribology and biological behaviour of nanocrystalline diamond coatings, and blood compatibility of diamond-like carbon coatings. Part two then goes on to review biomedical applications of diamond based materials, beginning with nanostructured diamond coatings for orthopaedic applications. Topics explored include ultrananocrystalline diamond for neural and ophthalmologi...

  17. Analysis of diamond-like carbon and Ti/MoS2 coatings on Ti-6Al-4V substrates for applicability to turbine engine applications

    International Nuclear Information System (INIS)

    Wu, L.; Holloway, B.C.; Kalil, C.; Manos, D.M.

    2000-01-01

    Ti-6Al-4V substrates have been coated by diamond-like carbon (DLC) films, with no surface pretreatment, and have been coated by Ti/MoS 2 films, with a simple surface pre-cleaning. The DLC films were deposited by planar coil r.f. inductively-coupled plasma-enhanced chemical vapor deposition (r.f. ICPECVD); the Ti/MoS 2 films were deposited by magnetron sputtering. Both the DLC and Ti/MoS 2 films were characterized by pull tests, hardness tests, scanning electron microscopy (SEM), and wear tests (pin-on-disk and block-on-ring) to compare their adhesion, hardness, surface topology, and wear properties to plasma-sprayed Cu-Ni-In coating currently used for turbine engine applications. The DLC films were easily characterized by their optical properties because they were highly transparent. We used variable-angle spectroscopic ellipsometry (VASE) to characterize thickness and to unequivocally extract real and complex index of refraction, providing a rapid assessment of film quality. Thicker coatings yielded the largest hardness values. The DLC coatings did not require abrasive pretreatment or the formation of bond-layers to ensure good adhesion to the substrate. Simple surface pre-cleaning was also adequate to form well-adhered Ti/MoS 2 on Ti-6Al-4V. The results show that the DLC and Ti/MoS 2 coatings are both much better fretting- and wear-resistant coatings than plasma-sprayed Cu-Ni-In. Both show excellent adhesion to the substrates, less surface roughness, harder surfaces, and more wear resistance than the Cu-Ni-In films. (orig.)

  18. Electrochemical Evaluation of Si-Incorporated Diamond-Like Carbon (DLC) Coatings Deposited on STS 316L and Ti Alloy for Biomedical Applications

    International Nuclear Information System (INIS)

    Kim, Jung Gu; Lee, Kwang Ryeol; Kim, Young Sik; Hwang, Woon Suk

    2007-01-01

    DLC coatings have been deposited onto substrate of STS 316L and Ti alloy using r.f. PACVD (plasma-assisted chemical vapor deposition) with a mixture of C 6 H 6 and SiH 4 as the process gases. Corrosion performance of DLC coatings was investigated by electrochemical techniques (potentiodynamic polarization test and electrochemical impedance spectroscopy) and surface analysis (scanning electron microscopy). the electrolyte used in this test was a 0.89% NaCl solution of pH 7.4 at temperature 37 .deg. C. The porosity and protective efficiency of DLC coatings were obtained using potentiodynamic polarization test. Moreover, the delamination area and volume fraction of water uptake of DLC coatings ass a function of immersion time were calculated using electrochemical impedance spectroscopy. This study provides the reliable and quantitative data for assessment of the effect of substrate on corrosion performance of Si-DLC coatings. the results showed that Si-DLC coating on Ti alloy could improve corrosion resistance more than that on STS 316L in the simulated body fluid environment. This could be attributed to the formation of a dense and low-porosity coating, which impedes the penetration of water and ions

  19. Deposition characteristics of titanium coating deposited on SiC fiber by cold-wall chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Xian, E-mail: luo_shenfan@hotmail.com; Wu, Shuai; Yang, Yan-qing; Jin, Na; Liu, Shuai; Huang, Bin

    2016-12-01

    The deposition characteristics of titanium coating on SiC fiber using TiCl{sub 4}-H{sub 2}-Ar gas mixture in a cold-wall chemical vapor deposition were studied by the combination of thermodynamic analysis and experimental studies. The thermodynamic analysis of the reactions in the TiCl{sub 4}-H{sub 2}-Ar system indicates that TiCl{sub 4} transforms to titanium as the following paths: TiCl{sub 4} → TiCl{sub 3} → Ti, or TiCl{sub 4} → TiCl{sub 3} → TiCl{sub 2} → Ti. The experimental results show that typical deposited coating contains two distinct layers: a TiC reaction layer close to SiC fiber and titanium coating which has an atomic percentage of titanium more than 70% and that of carbon lower than 30%. The results illustrate that a carbon diffusion barrier coating needs to be deposited if pure titanium is to be prepared. The deposition rate increases with the increase of temperature, but higher temperature has a negative effect on the surface uniformity of titanium coating. In addition, appropriate argon gas flow rate has a positive effect on smoothing the surface morphology of the coating. - Highlights: • Both thermodynamic analysis and experimental studies were adopted in this work. • The transformation paths of TiCl{sub 4} to Ti is: TiCl{sub 4} → TiCl{sub 3} → Ti, or TiCl{sub 4} → TiCl{sub 3} → TiCl{sub 2} → Ti. • Typical deposited Ti coating on SiC fiber contained two distinct layers. • Deposition temperature is important on deposition rate and morphologies. • Appropriate argon gas flow rate has a positive effect on smoothing of the coating.

  20. Spray-loading: A cryogenic deposition method for diamond anvil cell

    Science.gov (United States)

    Scelta, Demetrio; Ceppatelli, Matteo; Ballerini, Riccardo; Hajeb, Ahmed; Peruzzini, Maurizio; Bini, Roberto

    2018-05-01

    An efficient loading technique has been developed for flammable, toxic, or explosive gases which can be condensed at liquid nitrogen temperature and ambient pressure in membrane diamond anvil cells (DACs). This cryogenic technique consists in a deposition of small quantities of the desired gas directly into the sample chamber. The deposition is performed using a capillary that reaches the space between the diamond anvils. The DAC is kept under inert gas overpressure during the whole process, in order to avoid contamination from atmospheric O2, CO2, and H2O. This technique provides significant advantages over standard cryo-loading and gas-loading when the condensation of dangerous samples at liquid nitrogen temperature raises safety concerns because it allows dealing with minimum quantities of condensed gases. The whole procedure is particularly fast and efficient. The "spray-loading" has been successfully used in our laboratory to load several samples including acetylene, ammonia, ethylene, and carbon dioxide/water or red phosphorus/NH3 mixtures.

  1. Thermoluminescence characterisation of chemical vapour deposited diamond films

    CERN Document Server

    Mazzocchi, S; Bucciolini, M; Cuttone, G; Pini, S; Sabini, M G; Sciortino, S

    2002-01-01

    The thermoluminescence (TL) characteristics of a set of six chemical vapour deposited diamond films have been studied with regard to their use as off-line dosimeters in radiotherapy. The structural characterisation has been performed by means of Raman spectroscopy. Their TL responses have been tested with radiotherapy beams ( sup 6 sup 0 Co photons, photons and electrons from a linear accelerator (Linac), 26 MeV protons from a TANDEM accelerator) in the dose range 0.1-7 Gy. The dosimetric characterisation has yielded a very good reproducibility, a very low dependence of the TL response on the type of particle and independence of the radiation energy. The TL signal is not influenced by the dose rate and exhibits a very low thermal fading. Moreover, the sensitivity of the diamond samples compares favourably with that of standard TLD100 dosimeters.

  2. Room temperature diamond-like carbon coatings produced by low energy ion implantation

    Energy Technology Data Exchange (ETDEWEB)

    Markwitz, A., E-mail: a.markwitz@gns.cri.nz [Department for Ion Beam Technologies, GNS Science, 30 Gracefield Road, Lower Hutt (New Zealand); The MacDiarmid Institute for Advanced Materials and Nanotechnology (New Zealand); Mohr, B.; Leveneur, J. [Department for Ion Beam Technologies, GNS Science, 30 Gracefield Road, Lower Hutt (New Zealand)

    2014-07-15

    Nanometre-smooth diamond-like carbon coatings (DLC) were produced at room temperature with ion implantation using 6 kV C{sub 3}H{sub y}{sup +} ion beams. Ion beam analysis measurements showed that the coatings contain no heavy Z impurities at the level of 100 ppm, have a homogeneous stoichiometry in depth and a hydrogen concentration of typically 25 at.%. High resolution TEM analysis showed high quality and atomically flat amorphous coatings on wafer silicon. Combined TEM and RBS analysis gave a coating density of 3.25 g cm{sup −3}. Raman spectroscopy was performed to probe for sp{sup 2}/sp{sup 3} bonds in the coatings. The results indicate that low energy ion implantation with 6 kV produces hydrogenated amorphous carbon coatings with a sp{sup 3} content of about 20%. Results highlight the opportunity of developing room temperature DLC coatings with ion beam technology for industrial applications.

  3. Antithrombogenicity of Fluorinated Diamond-Like Carbon Films Coated Nano Porous Polyethersulfone (PES Membrane

    Directory of Open Access Journals (Sweden)

    Norihisa Miki

    2013-09-01

    Full Text Available A nano porous polyethersulfone (PES membrane is widely used for aspects of nanofiltration, such as purification, fractionation and dialysis. However, the low-blood-compatibility characteristic of PES membrane causes platelets and blood cells to stick to the surface of the membrane and degrades ions diffusion through membrane, which further limits its application for dialysis systems. In this study, we deposited the fluorinated-diamond-like-carbon (F-DLC onto the finger like structure layer of the PES membrane. By doing this, we have the F-DLC films coating the membrane surface without sacrificing the membrane permeability. In addition, we examined antithrombogenicity of the F-DLC/PES membranes using a microfluidic device, and experimentally found that F-DLC drastically reduced the amount of blood cells attached to the surface. We have also conducted long-term experiments for 24 days and the diffusion characteristics were found to be deteriorated due to fouling without any surface modification. On the other hand, the membranes coated by F-DLC film gave a consistent diffusion coefficient of ions transfer through a membrane porous. Therefore, F-DLC films can be a great candidate to improve the antithrombogenic characteristics of the membrane surfaces in hemodialysis systems.

  4. CVD of alternated microcrystalline (MCD) and nanocrystalline (NCD) diamond films on WC-TIC-CO substrates

    International Nuclear Information System (INIS)

    Campos, Raonei Alves; Contin, Andre; Trava-Airoldi, Vladimir J.; Corat, Evaldo Jose; Barquete, Danilo Maciel

    2010-01-01

    CVD Diamond coating of WC-TiC-Co cutting tools has been an alternative to increase tool lifetime. Experiments have shown that residual stresses produced during films growth on WC-TiC-Co substrates significantly increases with increasing film thickness up to 20 μm and usually leads to film delamination. In this work alternated micro- and nanocrystalline CVD diamond films have been used to relax interface stresses and to increase diamond coatings performance. WC-TiC-Co substrates have been submitted to a boronizing thermal diffusion treatment prior to CVD diamond films growth. After reactive heat treatment samples were submitted to chemical etching in acid and alkaline solution. The diamond films deposition was performed using HFCVD reactor with different gas concentrations for microcrystalline (MCD) and nano-crystalline (NCD) films growth. As a result, we present the improvement of diamond films adherence on WC-TiC-Co, evaluated by indentation and machining tests. Samples were characterized by Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) for qualitative analysis of diamond films. X-ray Diffraction (XRD) was used for phases identification after boronizing process. Diamond film compressive residual stresses were analyzed by Raman Scattering Spectroscopy (RSS). (author)

  5. Adhesive bonding and brazing of nanocrystalline diamond foil onto different substrate materials

    Science.gov (United States)

    Lodes, Matthias A.; Sailer, Stefan; Rosiwal, Stefan M.; Singer, Robert F.

    2013-10-01

    Diamond coatings are used in heavily stressed industrial applications to reduce friction and wear. Hot-filament chemical vapour deposition (HFCVD) is the favourable coating method, as it allows a coating of large surface areas with high homogeneity. Due to the high temperatures occurring in this CVD-process, the selection of substrate materials is limited. With the desire to coat light materials, steels and polymers a new approach has been developed. First, by using temperature-stable templates in the HFCVD and stripping off the diamond layer afterwards, a flexible, up to 150 μm thick and free standing nanocrystalline diamond foil (NCDF) can be produced. Afterwards, these NCDF can be applied on technical components through bonding and brazing, allowing any material as substrate. This two-step process offers the possibility to join a diamond layer on any desired surface. With a modified scratch test and Rockwell indentation testing the adhesion strength of NCDF on aluminium and steel is analysed. The results show that sufficient adhesion strength is reached both on steel and aluminium. The thermal stress in the substrates is very low and if failure occurs, cracks grow undercritically. Adhesion strength is even higher for the brazed samples, but here crack growth is critical, delaminating the diamond layer to some extent. In comparison to a sample directly coated with diamond, using a high-temperature CVD interlayer, the brazed as well as the adhesively bonded samples show very good performance, proving their competitiveness. A high support of the bonding layer could be identified as crucial, though in some cases a lower stiffness of the latter might be acceptable considering the possibility to completely avoid thermal stresses which occur during joining at higher temperatures.

  6. Tribological performance of hard carbon coatings on 440C bearing steel

    Energy Technology Data Exchange (ETDEWEB)

    Kustas, F M; Misra, M S; Shepard, D F; Froechtenigt, J F [Martin Marietta Astronautics Group, Denver, CO (United States)

    1991-11-01

    Hard carbon coatings such as amorphous carbon, diamond and diamond-like carbon have received considerable attention for tribological applications owing to their high hardness, high modulus and desirable surface properties. Unfortunately, most of the deposition techniques induce high substrate temperatures that would temper traditional bearing steels and reduce the substrate load-carrying capability. Therefore, to effectively use these desirable coatings, a lower temperature deposition technique is required. Ion beam deposition can provide essentially ambient temperature conditions, accurate control of process parameters and good coating-substrate adhesion. To use these attributes, a test program was initiated to deposit mass-analyzed, high purity C{sup +} and CH{sub 4}{sup +} ions on molybdenum and 440C bearing steel for subsequent characterization by Raman spectroscopy and friction-wear tests. Results for a coating deposited from a carbon monoxide source showed an amorphous carbon-microcrystalline graphtie structure which exhibited very high microhardness and a three fold reduction in coefficient of friction for unlubricated tests compared to untreated 440C steel. In addition, incrementally increasing the applied load (by up to a factor of 5) resulted in progressively lower coefficients of friction, which conforms to solid lubrication theory. End-of-travel wear debris and some limited coating delamination were observed within thinner areas of the coating. Therefore an amorphous carbon-graphite coating applied to 440C steel at ambient temperature exhibits solid lubricating film characteristics with high load-carrying capability. (orig.).

  7. Magnetron reactively sputtered Ti-DLC coatings on HNBR rubber : The influence of substrate bias

    NARCIS (Netherlands)

    Bui, X.L.; Pei, Y.T.; Hosson, J.Th.M. De

    2008-01-01

    In this study, Ti-containing diamond-like carbon (Ti-DLC) coatings have been deposited on HNBR (hydrogenated nitrile butadiene) rubber and also on Si wafer as reference via unbalanced magnetroli reactive sputtering from a Ti target in C2H2/Ar plasma. The deposition rates of coatings on rubber and Si

  8. Low-temperature synthesis of diamond films by photoemission-assisted plasma-enhanced chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Kawata, Mayuri, E-mail: kawata@mail.tagen.tohoku.ac.jp; Ojiro, Yoshihiro; Ogawa, Shuichi; Takakuwa, Yuji [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Masuzawa, Tomoaki; Okano, Ken [International Christian University, 3-10-2 Osawa, Mitaka 181-8585 (Japan)

    2014-03-15

    Photoemission-assisted plasma-enhanced chemical vapor deposition (PA-PECVD), a process in which photoelectrons emitted from a substrate irradiated with ultraviolet light are utilized as a trigger for DC discharge, was investigated in this study; specifically, the DC discharge characteristics of PA-PECVD were examined for an Si substrate deposited in advance through hot-filament chemical vapor deposition with a nitrogen-doped diamond layer of thickness ∼1 μm. Using a commercially available Xe excimer lamp (hν = 7.2 eV) to illuminate the diamond surface with and without hydrogen termination, the photocurrents were found to be 3.17 × 10{sup 12} and 2.11 × 10{sup 11} electrons/cm{sup 2}/s, respectively. The 15-fold increase in photocurrent was ascribed to negative electron affinity (NEA) caused by hydrogen termination on the diamond surfaces. The DC discharge characteristics revealed that a transition bias voltage from a Townsend-to-glow discharge was considerably decreased because of NEA (from 490 to 373 V for H{sub 2} gas and from 330 to 200 V for Ar gas), enabling a reduction in electric power consumption needed to synthesize diamond films through PA-PECVD. In fact, the authors have succeeded in growing high-quality diamond films of area 2.0 cm{sup 2} at 540 °C with a discharge power of only 1.8 W, plasma voltage of 156.4 V, and discharge current of 11.7 mA under the glow discharge of CH{sub 4}/H{sub 2}/Ar mixed gases. In addition to having only negligible amounts of graphite and amorphous carbon, the diamond films exhibit a relatively high diamond growth rate of 0.5 μm/h at temperatures as low as 540 °C, which is attributed to Ar{sup +} ions impinging on the diamond surface, and causing the removal of hydrogen atoms from the surface through sputtering. This process leads to enhanced CH{sub x} radical adsorption, because the sample was applied with a negative potential to accelerate photoelectrons in PA-PECVD.

  9. Biocompatible Silver-containing a-C:H and a-C coatings: AComparative Study

    Energy Technology Data Exchange (ETDEWEB)

    Endrino, Jose Luis; Allen, Matthew; Escobar Galindo, Ramon; Zhang, Hanshen; Anders, Andre; Albella, Jose Maria

    2007-04-01

    Hydrogenated diamond-like-carbon (a-C:H) and hydrogen-free amorphous carbon (a-C) coatings are known to be biocompatible and have good chemical inertness. For this reason, both of these materials are strong candidates to be used as a matrix that embeds metallic elements with antimicrobial effect. In this comparative study, we have incorporated silver into diamond-like carbon (DLC) coatings by plasma based ion implantation and deposition (PBII&D) using methane (CH4) plasma and simultaneously depositing Ag from a pulsed cathodic arc source. In addition, we have grown amorphous carbon - silver composite coatings using a dual-cathode pulsed filtered cathodic-arc (FCA) source. The silver atomic content of the deposited samples was analyzed using glow discharge optical spectroscopy (GDOES). In both cases, the arc pulse frequency of the silver cathode was adjusted in order to obtain samples with approximately 5 at.% of Ag. Surface hardness of the deposited films was analyzed using the nanoindentation technique. Cell viability for both a-C:H/Ag and a-C:/Ag samples deposited on 24-well tissue culture plates has been evaluated.

  10. Diamond Synthesis Employing Nanoparticle Seeds

    Science.gov (United States)

    Uppireddi, Kishore (Inventor); Morell, Gerardo (Inventor); Weiner, Brad R. (Inventor)

    2014-01-01

    Iron nanoparticles were employed to induce the synthesis of diamond on molybdenum, silicon, and quartz substrates. Diamond films were grown using conventional conditions for diamond synthesis by hot filament chemical vapor deposition, except that dispersed iron oxide nanoparticles replaced the seeding. This approach to diamond induction can be combined with dip pen nanolithography for the selective deposition of diamond and diamond patterning while avoiding surface damage associated to diamond-seeding methods.

  11. Electrophoretic deposition of composite hydroxyapatite-chitosan coatings

    International Nuclear Information System (INIS)

    Pang Xin; Zhitomirsky, Igor

    2007-01-01

    Cathodic electrophoretic deposition has been utilized for the fabrication of composite hydroxyapatite-chitosan coatings on 316L stainless steel substrates. The addition of chitosan to the hydroxyapatite suspensions promoted the electrophoretic deposition of the hydroxyapatite nanoparticles and resulted in the formation of composite coatings. The obtained coatings were investigated by X-ray diffraction, thermogravimetric and differential thermal analysis, scanning and transmission electron microscopy, potentiodynamic polarization measurements, and electrochemical impedance spectroscopy. It was shown that the deposit composition can be changed by a variation of the chitosan or hydroxyapatite concentration in the solutions. Experimental conditions were developed for the fabrication of hydroxyapatite-chitosan nanocomposites containing 40.9-89.8 wt.% hydroxyapatite. The method enabled the formation of adherent and uniform coatings of thicknesses up to 60 μm. X-ray studies revealed that the preferred orientation of the hydroxyapatite nanoparticles in the chitosan matrix increases with decreasing hydroxyapatite content in the composite coatings. The obtained coatings provided the corrosion protection for the 316L stainless steel substrates

  12. Flexible diamond-like carbon thin film coated on rubbers: fundamentals and applications

    NARCIS (Netherlands)

    Pei, Yutao

    2015-01-01

    Dynamic rubber seals are the major source of friction in lubrication systems and bearings, which may take up to 70% of the total friction. Our solution is to coat rubbers with flexible diamond-like carbon (DLC) thin film by which the coefficient of friction is reduced from above 1.5 to below 0.15.

  13. Designing 3D Multihierarchical Heteronanostructures for High-Performance On-Chip Hybrid Supercapacitors: Poly(3,4-(ethylenedioxy)thiophene)-Coated Diamond/Silicon Nanowire Electrodes in an Aprotic Ionic Liquid.

    Science.gov (United States)

    Aradilla, David; Gao, Fang; Lewes-Malandrakis, Georgia; Müller-Sebert, Wolfgang; Gentile, Pascal; Boniface, Maxime; Aldakov, Dmitry; Iliev, Boyan; Schubert, Thomas J S; Nebel, Christoph E; Bidan, Gérard

    2016-07-20

    A versatile and robust hierarchically multifunctionalized nanostructured material made of poly(3,4-(ethylenedioxy)thiophene) (PEDOT)-coated diamond@silicon nanowires has been demonstrated to be an excellent capacitive electrode for supercapacitor devices. Thus, the electrochemical deposition of nanometric PEDOT films on diamond-coated silicon nanowire (SiNW) electrodes using N-methyl-N-propylpyrrolidinium bis((trifluoromethyl)sulfonyl)imide ionic liquid displayed a specific capacitance value of 140 F g(-1) at a scan rate of 1 mV s(-1). The as-grown functionalized electrodes were evaluated in a symmetric planar microsupercapacitor using butyltrimethylammonium bis((trifluoromethyl)sulfonyl)imide aprotic ionic liquid as the electrolyte. The device exhibited extraordinary energy and power density values of 26 mJ cm(-2) and 1.3 mW cm(-2) within a large voltage cell of 2.5 V, respectively. In addition, the system was able to retain 80% of its initial capacitance after 15 000 galvanostatic charge-discharge cycles at a high current density of 1 mA cm(-2) while maintaining a Coulombic efficiency around 100%. Therefore, this multifunctionalized hybrid device represents one of the best electrochemical performances concerning coated SiNW electrodes for a high-energy advanced on-chip supercapacitor.

  14. FY 2000 report on the results of the regional consortium R and D project - Regional new technology creation R and D. First year report. Functional molds with highly polished diamond coatings; 2000 nendo chiiki consortium kenkyu kaihatsu jigyo - chiiki shingijutsu soshutsu kenkyu kaihatsu. Kyomen diamond maku wo yusuru kokino kanagata (shonendo) seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    The development was proceeded with of the technology to form the uniform diamond coating on mold with the complicated shape and also to highly polish it by a new chemical polishing method. The new chemical polishing method is a method using TiAlX intermetallic compounds as grindstone. Reaction with each other of Ti and C by frictional heat expedites diamond polishing. 1) development of the controlling technology of diamond coating interface; 2) development of the 3-D diamond polishing system; 3) demonstrative test on diamond coating; 4) study of a possibility of the commercialization. 1) was divided into the development of the controlling technology of diamond coating interface and the survey of super-hard alloys suitable for diamond coating formation. In the latter, it was found out that the highly Co containing particular WC super-hard alloys were bad in adhesiveness to diamond coating. Therefore, studies were made on the manufacturing of super-hard alloys which use coarse WC only near the surface and does not have much Co and on the use of SiC excellent in adhesiveness both to super-hard alloys and diamond for intermediate layer. (NEDO)

  15. Plasma sprayed and electrospark deposited zirconium metal diffusion barrier coatings

    International Nuclear Information System (INIS)

    Hollis, Kendall J.; Pena, Maria I.

    2010-01-01

    Zirconium metal coatings applied by plasma spraying and electrospark deposition (ESD) have been investigated for use as diffusion barrier coatings on low enrichment uranium fuel for research nuclear reactors. The coatings have been applied to both stainless steel as a surrogate and to simulated nuclear fuel uranium-molybdenum alloy substrates. Deposition parameter development accompanied by coating characterization has been performed. The structure of the plasma sprayed coating was shown to vary with transferred arc current during deposition. The structure of ESD coatings was shown to vary with the capacitance of the deposition equipment.

  16. Investigation of the nucleation process of chemical vapour deposited diamond films

    International Nuclear Information System (INIS)

    Katai, S.

    2001-01-01

    The primary aim of this work was to contribute to the understanding of the bias enhanced nucleation (BEN) process during the chemical vapour deposition (CVD) of diamond on silicon. The investigation of both the gas phase environment above the substrate surface, by in situ mass selective energy analysis of ions, and of the surface composition and structure by in vacuo surface analytic methods (XPS, EELS) have been carried out. In both cases, the implementation of these measurements required the development and construction of special experimental apparatus as well. The secondary aim of this work was to give orientation to our long term goal of growing diamond films with improved quality. For this reason, (1) contaminant levels at the diamond-silicon interface after growth were studied by SIMS, (2) the internal stress distribution of highly oriented free-standing diamond films were studied by Raman spectroscopy, and (3) an attempt was made to produce spatially regular oriented nuclei formation by nucleating on a pattern created by laser treatment on silicon substrates. (orig.)

  17. Diamond pixel modules

    International Nuclear Information System (INIS)

    Asner, D.; Barbero, M.; Bellini, V.; Belyaev, V.; Brom, J-M.; Bruzzi, M.; Chren, D.; Cindro, V.; Claus, G.; Cristinziani, M.; Costa, S.; D'Alessandro, R.; Boer, W. de; Dobos, D.; Dolenc, I.; Dulinski, W.; Duris, J.; Eremin, V.; Eusebi, R.; Frais-Koelbl, H.

    2011-01-01

    With the commissioning of the LHC in 2010 and upgrades expected in 2015, ATLAS and CMS are planning to upgrade their innermost tracking layers with radiation hard technologies. Chemical Vapor Deposition diamond has been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle, CDF and all LHC experiments. This material is now being considered as a sensor material for use very close to the interaction region where the most extreme radiation conditions exist. Recently the RD42 collaboration constructed, irradiated and tested polycrystalline and single-crystal chemical vapor deposition diamond sensors to the highest fluences expected at the super-LHC. We present beam test results of chemical vapor deposition diamond up to fluences of 1.8x10 16 protons/cm 2 illustrating that both polycrystalline and single-crystal chemical vapor deposition diamonds follow a single damage curve. We also present beam test results of irradiated complete diamond pixel modules.

  18. Diamond pixel modules

    Energy Technology Data Exchange (ETDEWEB)

    Asner, D. [Carleton University, Ottawa (Canada); Barbero, M. [Universitaet Bonn (Germany); Bellini, V. [INFN/University of Catania (Italy); Belyaev, V. [MEPHI Institute, Moscow (Russian Federation); Brom, J-M. [IPHC, Strasbourg (France); Bruzzi, M. [INFN/University of Florence (Italy); Chren, D. [Czech Technical University, Prague (Czech Republic); Cindro, V. [Jozef Stefan Institute, Ljubljana (Slovenia); Claus, G. [IPHC, Strasbourg (France); Cristinziani, M. [Universitaet Bonn (Germany); Costa, S. [INFN/University of Catania (Italy); D' Alessandro, R. [Department of Energetics/INFN Florence (Italy); Boer, W. de [Universitaet Karlsruhe, Karlsruhe (Germany); Dobos, D. [CERN, Geneva (Switzerland); Dolenc, I. [Jozef Stefan Institute, Ljubljana (Slovenia); Dulinski, W. [IPHC, Strasbourg (France); Duris, J. [UCLA, Los Angeles, CA (United States); Eremin, V. [Ioffe Institute, St. Petersburg (Russian Federation); Eusebi, R. [FNAL, Batavia (United States); Frais-Koelbl, H. [Fachhochschule fuer Wirtschaft und Technik, Wiener Neustadt (Austria)

    2011-04-21

    With the commissioning of the LHC in 2010 and upgrades expected in 2015, ATLAS and CMS are planning to upgrade their innermost tracking layers with radiation hard technologies. Chemical Vapor Deposition diamond has been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle, CDF and all LHC experiments. This material is now being considered as a sensor material for use very close to the interaction region where the most extreme radiation conditions exist. Recently the RD42 collaboration constructed, irradiated and tested polycrystalline and single-crystal chemical vapor deposition diamond sensors to the highest fluences expected at the super-LHC. We present beam test results of chemical vapor deposition diamond up to fluences of 1.8x10{sup 16} protons/cm{sup 2} illustrating that both polycrystalline and single-crystal chemical vapor deposition diamonds follow a single damage curve. We also present beam test results of irradiated complete diamond pixel modules.

  19. Structure and properties of diamond and diamond-like films

    Energy Technology Data Exchange (ETDEWEB)

    Clausing, R.E. [Oak Ridge National Lab., TN (United States)

    1993-01-01

    This section is broken into four parts: (1) introduction, (2) natural IIa diamond, (3) importance of structure and composition, and (4) control of structure and properties. Conclusions of this discussion are that properties of chemical vapor deposited diamond films can compare favorably with natural diamond, that properties are anisotropic and are a strong function of structure and crystal perfection, that crystal perfection and morphology are functions of growth conditions and can be controlled, and that the manipulation of texture and thereby surface morphology and internal crystal perfection is an important step in optimizing chemically deposited diamond films for applications.

  20. Influence of deposition parameters on morphological properties of biomedical calcium phosphate coatings prepared using electrostatic spray deposition

    International Nuclear Information System (INIS)

    Leeuwenburgh, S.C.G.; Wolke, J.G.C.; Schoonman, J.; Jansen, J.A.

    2005-01-01

    In order to deposit biomedical calcium phosphate (CaP) coatings with a defined surface morphology, the electrostatic spray deposition (ESD) technique was used since this technique offers the possibility to deposit ceramic coatings with a variety of surface morphologies. A scanning electron microscopical study was performed in order to investigate the influence of several deposition parameters on the final morphology of the deposited coatings. The chemical characteristics of the coatings were studied by means of X-ray diffraction and Fourier-transform infrared spectroscopy. Regarding the chemical coating properties, the results showed that the coatings can be described as crystalline carbonate apatite coatings, a crystal phase which is similar to the mineral phase of bone and teeth. The morphology of CaP coatings, deposited using the ESD technique, was strongly dependent on the deposition parameters. By changing the nozzle-to-substrate distance, the precursor liquid flow rate and the deposition temperature, coating morphologies were deposited, which varied from dense to highly porous, reticular morphologies. The formation of various morphologies was the result of an equilibrium between the relative rates of CaP solute precipitation/reaction, solvent evaporation and droplet spreading onto the substrate surface

  1. Thermally stable diamond brazing

    Science.gov (United States)

    Radtke, Robert P [Kingwood, TX

    2009-02-10

    A cutting element and a method for forming a cutting element is described and shown. The cutting element includes a substrate, a TSP diamond layer, a metal interlayer between the substrate and the diamond layer, and a braze joint securing the diamond layer to the substrate. The thickness of the metal interlayer is determined according to a formula. The formula takes into account the thickness and modulus of elasticity of the metal interlayer and the thickness of the TSP diamond. This prevents the use of a too thin or too thick metal interlayer. A metal interlayer that is too thin is not capable of absorbing enough energy to prevent the TSP diamond from fracturing. A metal interlayer that is too thick may allow the TSP diamond to fracture by reason of bending stress. A coating may be provided between the TSP diamond layer and the metal interlayer. This coating serves as a thermal barrier and to control residual thermal stress.

  2. Surface coatings deposited by CVD and PVD

    International Nuclear Information System (INIS)

    Gabriel, H.M.

    1982-01-01

    The demand for wear and corrosion protective coatings is increasing due to economic facts. Deposition processes in gas atmospheres like the CVD and PVD processes attained a tremendous importance especially in the field of the deposition of thin hard refractory and ceramic coatings. CVD and PVD processes are reviewed in detail. Some examples of coating installations are shown and numerous applications are given to demonstrate the present state of the art. (orig.) [de

  3. Non-Lubricated Diamond-Coated Bearings Reinforced by Carbon Fibers to Work in Lunar Dust, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — In Phase I, we made prototype sliding bearings from functionally-graded, diamond-coated carbon-fiber reinforced composite. In dry-sliding experiments, the friction...

  4. Structure and Properties of Diamond-Like Carbon Films Deposited by PACVD Technique on Light Alloys

    Directory of Open Access Journals (Sweden)

    Tański T.

    2016-09-01

    Full Text Available The investigations presented in this paper describe surface treatment performed on samples of heat-treated cast magnesium and aluminium alloy. The structure and chemical composition as well as the functional and mechanical properties of the obtained gradient/monolithic films were analysed by high resolution transmission electron microscopy and scanning electron microscopy, Raman spectroscopy, the ball-on-disk tribotester and scratch testing. Moreover, investigation of the electrochemical corrosion behaviour of the samples was carried out by means of potentiodynamic polarisation curves in 1-M NaCl solution. The coatings produced by chemical vapour deposition did not reveal any delamination or defects and they adhere closely to the substrate. The coating thickness was in a range of up to 2.5 microns. Investigations using Raman spectra of the DLC films confirmed a multiphase character of the diamond-like carbon layer, revealing the sp2 and sp3 electron hybridisation responsible for both the hardness and the friction coefficient. The best wear resistance test results were obtained for the magnesium alloy substrate - AZ61, for which the measured value of the friction path length was equal to 630 m.

  5. Electrophoretic deposition of zinc-substituted hydroxyapatite coatings.

    Science.gov (United States)

    Sun, Guangfei; Ma, Jun; Zhang, Shengmin

    2014-06-01

    Zinc-substituted hydroxyapatite nanoparticles synthesized by the co-precipitation method were used to coat stainless steel plates by electrophoretic deposition in n-butanol with triethanolamine as a dispersant. The effect of zinc concentration in the synthesis on the morphology and microstructure of coatings was investigated. It is found that the deposition current densities significantly increase with the increasing zinc concentration. The zinc-substituted hydroxyapatite coatings were analyzed by X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy. It is inferred that hydroxyapatite and triethanolamine predominate in the chemical composition of coatings. With the increasing Zn/Ca ratios, the contents of triethanolamine decrease in the final products. The triethanolamine can be burnt out by heat treatment. The tests of adhesive strength have confirmed good adhesion between the coatings and substrates. The formation of new apatite layer on the coatings has been observed after 7days of immersion in a simulated body fluid. In summary, the results show that dense, uniform zinc-substituted hydroxyapatite coatings are obtained by electrophoretic deposition when the Zn/Ca ratio reaches 5%. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Beam Tests of Diamond-Like Carbon Coating for Mitigation of Electron Cloud

    Energy Technology Data Exchange (ETDEWEB)

    Eldred, Jeffrey [Fermilab; Backfish, Michael [Fermilab; Kato, Shigeki [KEK, Tsukuba; Tan, Cheng-Yang [Fermilab; Zwaska, Robert [Fermilab

    2017-05-01

    Electron cloud beam instabilities are an important consideration in virtually all high-energy particle accelerators and could pose a formidable challenge to forthcoming high-intensity accelerator upgrades. Our results evaluate the efficacy of a diamond-like carbon (DLC) coating for the mitigation of electron in the Fermilab Main Injector. The interior surface of the beampipe conditions in response to electron bombardment from the electron cloud and we track the change in electron cloud flux over time in the DLC coated beampipe and uncoated stainless steel beampipe. The electron flux is measured by retarding field analyzers placed in a field-free region of the Main Injector. We find the DLC coating reduces the electron cloud signal to roughly 2\\% of that measured in the uncoated stainless steel beampipe.

  7. Adhesion enhancement of diamond-like carbon thin films on Ti alloys by incorporation of nanodiamond particles

    International Nuclear Information System (INIS)

    Zhang, C.Z.; Tang, Y.; Li, Y.S.; Yang, Q.

    2013-01-01

    Coating adherent diamond-like carbon (DLC) thin films directly on Ti alloys is technologically difficult. This research incorporates nanodiamond particles to form a diamond/DLC composite interlayer to enhance the adhesion of DLC thin films on Ti6Al4V substrates. Initially, nanodiamond particles were deposited on Ti6Al4V substrates by microwave plasma enhanced chemical vapor deposition from a methane–hydrogen gas mixture. A DLC thin film was then deposited, on top of the nanodiamond particles, by direct ion beam deposition. Scanning electron microscopy, Atomic force microscopy, X-ray Diffraction and Raman spectroscopy were used to characterize the microstructure and chemical bonding of the deposited particles and films, and Rockwell indentation testing was used to evaluate the adhesion of the deposited films. The results indicate that the pre-deposited nanodiamond particles significantly enhance the interfacial adhesion between the DLC thin film and the Ti6Al4V substrate, possibly by enhanced interfacial bonding, mechanical interlocking, and stress relief. - Highlights: ► Nanodiamond particles were deposited on Ti6Al4V before DLC deposition. ► Diamond/DLC composite film was formed by incorporation of nanodiamond particles. ► Greatly enhanced adhesion of diamond/DLC composite film on Ti6Al4V was achieved. ► Enhanced adhesion is by increased interfacial bonding and mechanical interlocking

  8. Adhesion enhancement of diamond-like carbon thin films on Ti alloys by incorporation of nanodiamond particles

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, C.Z.; Tang, Y. [Department of Mechanical Engineering, University of Saskatchewan, 57 Campus Drive, Saskatoon, SK, Canada S7N 5A9 (Canada); Li, Y.S. [Plasma Physics Laboratory, University of Saskatchewan, 116 Science Place, Saskatoon, SK, Canada S7N 5E2 (Canada); Yang, Q., E-mail: qiaoqin.yang@usask.ca [Department of Mechanical Engineering, University of Saskatchewan, 57 Campus Drive, Saskatoon, SK, Canada S7N 5A9 (Canada)

    2013-01-01

    Coating adherent diamond-like carbon (DLC) thin films directly on Ti alloys is technologically difficult. This research incorporates nanodiamond particles to form a diamond/DLC composite interlayer to enhance the adhesion of DLC thin films on Ti6Al4V substrates. Initially, nanodiamond particles were deposited on Ti6Al4V substrates by microwave plasma enhanced chemical vapor deposition from a methane–hydrogen gas mixture. A DLC thin film was then deposited, on top of the nanodiamond particles, by direct ion beam deposition. Scanning electron microscopy, Atomic force microscopy, X-ray Diffraction and Raman spectroscopy were used to characterize the microstructure and chemical bonding of the deposited particles and films, and Rockwell indentation testing was used to evaluate the adhesion of the deposited films. The results indicate that the pre-deposited nanodiamond particles significantly enhance the interfacial adhesion between the DLC thin film and the Ti6Al4V substrate, possibly by enhanced interfacial bonding, mechanical interlocking, and stress relief. - Highlights: ► Nanodiamond particles were deposited on Ti6Al4V before DLC deposition. ► Diamond/DLC composite film was formed by incorporation of nanodiamond particles. ► Greatly enhanced adhesion of diamond/DLC composite film on Ti6Al4V was achieved. ► Enhanced adhesion is by increased interfacial bonding and mechanical interlocking.

  9. Characterization of chemical vapour deposited diamond films: correlation between hydrogen incorporation and film morphology and quality

    International Nuclear Information System (INIS)

    Tang, C J; Neves, A J; Carmo, M C

    2005-01-01

    In order to tailor diamond synthesized through chemical vapour deposition (CVD) for different applications, many diamond films of different colours and variable quality were deposited by a 5 kW microwave plasma CVD reactor under different growth conditions. The morphology, quality and hydrogen incorporation of these films were characterized using scanning electron microscopy (SEM), Raman and Fourier-transform infrared (FTIR) spectroscopy, respectively. From this study, a general trend between hydrogen incorporation and film colour, morphology and quality was found. That is, as the films sorted by colour gradually become darker, ranging from white through grey to black, high magnification SEM images illustrate that the smoothness of the well defined crystalline facet gradually decreases and second nucleation starts to appear on it, indicating gradual degradation of the crystalline quality. Correspondingly, Raman spectra evidence that the diamond Raman peak at 1332 cm -1 becomes broader and the non-diamond carbon band around 1500 cm -1 starts to appear and becomes stronger, confirming increase of the non-diamond component and decrease of the phase purity of the film, while FTIR spectra show that the CH stretching band and the two CVD diamond specific peaks around 2830 cm -1 rise rapidly, and this indicates that the total amount of hydrogen incorporated into the film increases significantly

  10. Mo doped DLC nanocomposite coatings with improved mechanical and blood compatibility properties

    Energy Technology Data Exchange (ETDEWEB)

    Tang, X.S. [School of Physics Science and Technology, Zhanjiang Normal University, Zhanjiang 524048 (China); Development Center for New Materials Engineering and Technology in Universities of Guangdong, Zhanjiang 524048 (China); Wang, H.J.; Feng, L. [School of Physics Science and Technology, Zhanjiang Normal University, Zhanjiang 524048 (China); Shao, L.X. [School of Physics Science and Technology, Zhanjiang Normal University, Zhanjiang 524048 (China); Development Center for New Materials Engineering and Technology in Universities of Guangdong, Zhanjiang 524048 (China); Zou, C.W., E-mail: qingyihaiyanas@163.com [School of Physics Science and Technology, Zhanjiang Normal University, Zhanjiang 524048 (China); Development Center for New Materials Engineering and Technology in Universities of Guangdong, Zhanjiang 524048 (China)

    2014-08-30

    Highlights: • Mo doped diamond like carbon coatings were deposited by magnetron sputtering. • The blood compatibility of Mo-DLC coatings was observed through platelet adhesion. • The amount of thrombus on the Mo-DLC is much less than that of pyrolytic carbon. - Abstract: Mo (molybdenum) doped diamond like carbon (Mo-DLC) coatings with improved mechanical and blood compatibility properties were deposited by closed field unbalanced magnetron sputtering. The undoped and Mo-doped DLC coatings were analyzed by various characterization techniques such as Raman spectra, Atomic force microscopy, and temperature-dependent frictional wear testing. The results showed that the Mo-DLC coating with low Mo concentration was a effective protective coating with reduced residual stress and increased cohesive strength, and kept good wear resistance at the ambient temperature of 500 °C. The blood compatibility of Mo-DLC coatings was investigated by platelet adhesion. The results showed that the amount of thrombus on the Mo-DLC nanocomposite coatings was much less than that of thrombus on pyrolytic carbon films. The Mo-DLC nanocomposite coatings would be a new kind of promising materials applied to artificial heart valve and endovascula stent.

  11. Mo doped DLC nanocomposite coatings with improved mechanical and blood compatibility properties

    International Nuclear Information System (INIS)

    Tang, X.S.; Wang, H.J.; Feng, L.; Shao, L.X.; Zou, C.W.

    2014-01-01

    Highlights: • Mo doped diamond like carbon coatings were deposited by magnetron sputtering. • The blood compatibility of Mo-DLC coatings was observed through platelet adhesion. • The amount of thrombus on the Mo-DLC is much less than that of pyrolytic carbon. - Abstract: Mo (molybdenum) doped diamond like carbon (Mo-DLC) coatings with improved mechanical and blood compatibility properties were deposited by closed field unbalanced magnetron sputtering. The undoped and Mo-doped DLC coatings were analyzed by various characterization techniques such as Raman spectra, Atomic force microscopy, and temperature-dependent frictional wear testing. The results showed that the Mo-DLC coating with low Mo concentration was a effective protective coating with reduced residual stress and increased cohesive strength, and kept good wear resistance at the ambient temperature of 500 °C. The blood compatibility of Mo-DLC coatings was investigated by platelet adhesion. The results showed that the amount of thrombus on the Mo-DLC nanocomposite coatings was much less than that of thrombus on pyrolytic carbon films. The Mo-DLC nanocomposite coatings would be a new kind of promising materials applied to artificial heart valve and endovascula stent

  12. Post-deposition treatments of plasma-sprayed YBaCuO coatings deposited on nickel

    Energy Technology Data Exchange (ETDEWEB)

    Dube, D; Lambert, P; Arsenault, B; Champagne, B [National Research Council of Canada, Boucherville, PQ (Canada)

    1990-12-15

    As-sprayed YBaCuO coatings do not exhibit superconductivity because of the non-equilibrium solidification conditions of molten particles on the substrate and to the deposit's loss of oxygen. Therefore post-deposition treatments are required to restore the superconductivity. In this study, post-deposition treatments were carried out on thick YBaCuO coatings (200 {mu}m) deposited on cold nickel substrates to modify their microstructure, to restore the oxygen content and to improve their superconducting properties. These treatments consist in heating the coatings at various temperatures above 950deg C followed by controlled solidification cycles. The effect of these treatments on the microstructure of the coatings was assessed and the interaction between the coatings and the nickel substrate was also examined. Solidification cycles including a low cooling rate near the non-congruent melting temperature of YBa{sub 2}Cu{sub 3}O{sub x} and involving a temperature gradient were carried out to create a texture. (orig.).

  13. Nucleation and adhesion of diamond films on Co cemented tungsten carbide

    Energy Technology Data Exchange (ETDEWEB)

    Polini, R.; Santarelli, M.; Traversa, E.

    1999-12-01

    Diamond deposits were grown using hot filament chemical vapor deposition (CVD) on pretreated Co cemented tungsten carbide (WC-Co) substrates with an average grain size of 6 {micro}m. Depositions were performed with 0.5 or 1.0% methane concentration and with substrate temperatures ranging from 750 to 1,000 C. Diamond nucleation densities were measured by scanning electron microscopy. Scratched and bias-enhanced nucleation pretreated substrates showed the larger nucleation densities. Etching of the WC performed by Murakami's reagent, followed by surface-Co dissolution (MP pretreatment), led to a roughened but scarcely nucleating surface. The performance of a scratching prior to the MP pretreatment allowed one to increase the nucleation density, due scratching-induced defects, confined in the outermost layer of WC grains, which act as nucleation sites. Smaller nucleation densities were observed with increasing the substrate temperature and reducing the methane concentration, confirming that diamond nucleates via a heterogeneous process. The adhesion of continuous films was evaluated by the reciprocal of the slope of crack radius-indentation load functions. The substrate pretreatments mainly affected the film adhesion, while the influence of CVD process conditions was minor. The two main factors that improve the diamond film adhesion are the coating-substrate contact area and the surface-Co removal.

  14. Single crystal diamond detectors grown by chemical vapor deposition

    International Nuclear Information System (INIS)

    Tuve, C.; Angelone, M.; Bellini, V.; Balducci, A.; Donato, M.G.; Faggio, G.; Marinelli, M.; Messina, G.; Milani, E.; Morgada, M.E.; Pillon, M.; Potenza, R.; Pucella, G.; Russo, G.; Santangelo, S.; Scoccia, M.; Sutera, C.; Tucciarone, A.; Verona-Rinati, G.

    2007-01-01

    The detection properties of heteropitaxial (polycrystalline, pCVD) and homoepitaxial (single crystal, scCVD) diamond films grown by microwave chemical vapor deposition (CVD) in the Laboratories of Roma 'Tor Vergata' University are reported. The pCVD diamond detectors were tested with α-particles from different sources and 12 C ions produced by 15MV Tandem accelerator at Southern National Laboratories (LNS) in Catania (Italy). pCVDs were also used to monitor 14MeV neutrons produced by the D-T plasma at Joint European Torus (JET), Culham, U.K. The limit of pCVDs is the poor energy resolution. To overcome this problem, we developed scCVD diamonds using the same reactor parameters that optimized pCVD diamonds. scCVD were grown on a low cost (100) HPHT single crystal substrate. A detector 110μm thick was tested under α-particles and under 14MeV neutron irradiation. The charge collection efficiency spectrum measured under irradiation with a triple α-particle source shows three clearly resolved peaks, with an energy resolution of about 1.1%. The measured spectra under neutron irradiation show a well separated C(n,α 0 ) 9 Be12 reaction peak with an energy spread of 0.5MeV for 14.8MeV neutrons and 0.3MeV for 14.1MeV neutrons, which are fully compatible with the energy spread of the incident neutron beams

  15. Selective area deposition of diamond films on AlGaN/GaN heterostructures

    Czech Academy of Sciences Publication Activity Database

    Ižák, Tibor; Babchenko, Oleg; Jirásek, Vít; Vanko, G.; Vallo, M.; Vojs, M.; Kromka, Alexander

    2014-01-01

    Roč. 250, č. 12 (2014), 2574-2580 ISSN 0370-1972 R&D Projects: GA ČR(CZ) GP14-16549P Institutional support: RVO:68378271 Keywords : circular high electron mobility transistors * diamond films * GaN substrates * microwave chemical vapor deposition * selective area deposition Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.489, year: 2014

  16. Coating dental implant abutment screws with diamondlike carbon doped with diamond nanoparticles: the effect on maintaining torque after mechanical cycling.

    Science.gov (United States)

    Lepesqueur, Laura Soares; de Figueiredo, Viviane Maria Gonçalves; Ferreira, Leandro Lameirão; Sobrinho, Argemiro Soares da Silva; Massi, Marcos; Bottino, Marco Antônio; Nogueira Junior, Lafayette

    2015-01-01

    To determine the effect of maintaining torque after mechanical cycling of abutment screws that are coated with diamondlike carbon and coated with diamondlike carbon doped with diamond nanoparticles, with external and internal hex connections. Sixty implants were divided into six groups according to the type of connection (external or internal hex) and the type of abutment screw (uncoated, coated with diamondlike carbon, and coated with diamondlike carbon doped with diamond nanoparticles). The implants were inserted into polyurethane resin and crowns of nickel chrome were cemented on the implants. The crowns had a hole for access to the screw. The initial torque and the torque after mechanical cycling were measured. The torque values maintained (in percentages) were evaluated. Statistical analysis was performed using one-way analysis of variance and the Tukey test, with a significance level of 5%. The largest torque value was maintained in uncoated screws with external hex connections, a finding that was statistically significant (P = .0001). No statistically significant differences were seen between the groups with and without coating in maintaining torque for screws with internal hex connections (P = .5476). After mechanical cycling, the diamondlike carbon with and without diamond doping on the abutment screws showed no improvement in maintaining torque in external and internal hex connections.

  17. Hydrophilic nano-silica coating agents with platinum and diamond nanoparticles for denture base materials.

    Science.gov (United States)

    Yoshizaki, Taro; Akiba, Norihisa; Inokoshi, Masanao; Shimada, Masayuki; Minakuchi, Shunsuke

    2017-05-31

    Preventing microorganisms from adhering to the denture surface is important for ensuring the systemic health of elderly denture wearers. Silica coating agents provide high hydrophilicity but lack durability. This study investigated solutions to improve the durability of the coating layer, determine an appropriate solid content concentration of SiO 2 in the silica coating agent, and evaluate the effect of adding platinum (Pt) and diamond nanoparticles (ND) to the agent. Five coating agents were prepared with different SiO 2 concentrations with/without Pt and ND additives. The contact angle was measured, and the brush-wear test was performed. Scanning electron microscopy was used to investigate the silica coating layer. The appropriate concentration of SiO 2 was found to be 0.5-0.75 wt%. The coating agents with additives showed significantly high hydrophilicity immediately after coating and after the brush-wear test. The coating agents with/without additives formed a durable coating layer even after the brush-wear test.

  18. Biocompatibility and mechanical properties of diamond-like coatings on cobalt-chromium-molybdenum steel and titanium-aluminum-vanadium biomedical alloys.

    Science.gov (United States)

    Hinüber, C; Kleemann, C; Friederichs, R J; Haubold, L; Scheibe, H J; Schuelke, T; Boehlert, C; Baumann, M J

    2010-11-01

    Diamond-like carbon (DLC) films are favored for wear components because of diamond-like hardness, low friction, low wear, and high corrosion resistance (Schultz et al., Mat-wiss u Werkstofftech 2004;35:924-928; Lappalainen et al., J Biomed Mater Res B Appl Biomater 2003;66B:410-413; Tiainen, Diam Relat Mater 2001;10:153-160). Several studies have demonstrated their inertness, nontoxicity, and the biocompatibility, which has led to interest among manufacturers of surgical implants (Allen et al., J Biomed Mater Res B Appl Biomater 2001;58:319-328; Uzumaki et al., Diam Relat Mater 2006;15:982-988; Hauert, Diam Relat Mater 2003;12:583-589; Grill, Diam Relat Mater 2003;12:166-170). In this study, hydrogen-free amorphous, tetrahedrally bonded DLC films (ta-C) were deposited at low temperatures by physical vapor deposition on medical grade Co28Cr6Mo steel and the titanium alloy Ti6Al4V (Scheibe et al., Surf Coat Tech 1996;85:209-214). The mechanical performance of the ta-C was characterized by measuring its surface roughness, contact angle, adhesion, and wear behavior, whereas the biocompatibility was assessed by osteoblast (OB) attachment and cell viability via Live/Dead assay. There was no statistical difference found in the wettability as measured by contact angle measurements for the ta-C coated and the uncoated samples of either Co28Cr6Mo or Ti6Al4V. Rockwell C indentation and dynamic scratch testing on 2-10 μm thick ta-C films on Co28Cr6Mo substrates showed excellent adhesion with HF1 grade and up to 48 N for the critical load L(C2) during scratch testing. The ta-C coating reduced the wear from 3.5 × 10(-5) mm(3)/Nm for an uncoated control sample (uncoated Co28Cr6Mo against uncoated stainless steel) to 1.1 × 10(-7) mm(3)/Nm (coated Co28Cr6Mo against uncoated stainless steel) in reciprocating pin-on-disk testing. The lowest wear factor of 3.9 × 10(-10) mm(3)/Nm was measured using a ta-C coated steel ball running against a ta-C coated and polished Co28Cr6Mo disk

  19. A Study of Deposition Coatings Formed by Electroformed Metallic Materials.

    Directory of Open Access Journals (Sweden)

    Shoji Hayashi

    Full Text Available Major joining methods of dental casting metal include brazing and laser welding. However, brazing cannot be applied for electroformed metals since heat treatment could affect the fit, and, therefore, laser welding is used for such metals. New methods of joining metals that do not impair the characteristics of electroformed metals should be developed. When new coating is performed on the surface of the base metal, surface treatment is usually performed before re-coating. The effect of surface treatment is clinically evaluated by peeling and flex tests. However, these testing methods are not ideal for deposition coating strength measurement of electroformed metals. There have been no studies on the deposition coating strength and methods to test electroformed metals. We developed a new deposition coating strength test for electroformed metals. The influence of the negative electrolytic method, which is one of the electrochemical surface treatments, on the strength of the deposition coating of electroformed metals was investigated, and the following conclusions were drawn: 1. This process makes it possible to remove residual deposits on the electrodeposited metal surface layer. 2. Cathode electrolysis is a simple and safe method that is capable of improving the surface treatment by adjustments to the current supply method and current intensity. 3. Electrochemical treatment can improve the deposition coating strength compared to the physical or chemical treatment methods. 4. Electro-deposition coating is an innovative technique for the deposition coating of electroformed metal.

  20. Diamond films: Historical perspective

    Energy Technology Data Exchange (ETDEWEB)

    Messier, R. [Pennsylvania State Univ., University Park (United States)

    1993-01-01

    This section is a compilation of notes and published international articles about the development of methods of depositing diamond films. Vapor deposition articles are included from American, Russian, and Japanese publications. The international competition to develop new deposition methodologies is stressed. The current status of chemical vapor deposition of diamond is assessed.

  1. Fabrication of a miniature diamond grinding tool using a hybrid process of micro-EDM and co-deposition

    International Nuclear Information System (INIS)

    Chen, Shun-Tong; Lai, Yun-Cheng; Liu, Ching-Chang

    2008-01-01

    A novel miniature diamond grinding tool usable for the precise micro-grinding of miniature parts is presented. A hybrid process that combines 'micro-EDM' with 'precision co-deposition' is proposed. The metal substrate is micro-EDMed to a 50 µm diameter and micro diamonds with 0–2 µm grains are 'electroformed' on the substrate surface, producing a miniature multilayered grinding tool. Nickel and diamond act as binders and cutters, respectively. A partition plate with an array of drilled holes is designed to ensure good convection in the electroforming solution. The dispersion of diamond grains and displacement of nickel ions are noticeably improved. A miniature funnel mould enables the diamond grains to converge towards the cathode to increase their deposition probability on the substrate, thereby improving their distribution on the substrate surface. A micro ZrO 2 ceramic ferrule is finely ground by the developed grinding tool and then yields a surface roughness of R a = 0.085 µm. The proposed approach is applied during the final machining process

  2. Study of hard diamond-like carbon films deposited in an inductively coupled plasma source

    International Nuclear Information System (INIS)

    Yu Shiji; Ma Tengcai

    2003-01-01

    Chemical vapor deposition of the hard diamond-like carbon (DLC) films was achieved using an inductively coupled plasma source (ICPS). The microscopy, microhardness, deposition rate and structure characteristic of the DLC films were analyzed. It is shown that the ICPS is suitable for the hard DLC film deposition at relatively low substrate negative bias voltage, and the substrate negative bias voltage greatly affects chemical vapor deposition of the DLC film and its quality

  3. High-Current Cold Cathode Employing Diamond and Related Materials

    Energy Technology Data Exchange (ETDEWEB)

    Hirshfield, Jay L. [Omega-P, Inc., New Haven, CT (United States)

    2014-10-22

    The essence of this project was for diamond films to be deposited on cold cathodes to improve their emission properties. Films with varying morphology, composition, and size of the crystals were deposited and the emission properties of the cathodes that utilize such films were studied. The prototype cathodes fabricated by the methods developed during Phase I were tested and evaluated in an actual high-power RF device during Phase II. These high-power tests used the novel active RF pulse compression system and the X-band magnicon test facility at US Naval Research Laboratory. In earlier tests, plasma switches were employed, while tests under this project utilized electron-beam switching. The intense electron beams required in the switches were supplied from cold cathodes embodying diamond films with varying morphology, including uncoated molybdenum cathodes in the preliminary tests. Tests with uncoated molybdenum cathodes produced compressed X-band RF pulses with a peak power of 91 MW, and a maximum power gain of 16.5:1. Tests were also carried out with switches employing diamond coated cathodes. The pulse compressor was based on use of switches employing electron beam triggering to effect mode conversion. In experimental tests, the compressor produced 165 MW in a ~ 20 ns pulse at ~18× power gain and ~ 140 MW at ~ 16× power gain in a 16 ns pulse with a ~ 7 ns flat-top. In these tests, molybdenum blade cathodes with thin diamond coatings demonstrated good reproducible emission uniformity with a 100 kV, 100 ns high voltage pulse. The new compressor does not have the limitations of earlier types of active pulse compressors and can operate at significantly higher electric fields without breakdown.

  4. The effect of ion-beam induced strain on the nucleation density of chemical vapour deposited diamond

    International Nuclear Information System (INIS)

    Weiser, P.S.; Prawer, S.; Nugent, K.W.; Bettiol, A.A.; Kostidis, L.I.; Jamieson, D.N.

    1995-01-01

    The effect of ion implantation on the nucleation of CVD diamond on silicon and diamond substrates has been investigated. The strategy employed is to create laterally confined regions of strain in the substrates by focused MeV implantation of light ions. Raman Microscopy has been employed to obtain spatially resolved maps of the strain in these implanted regions. On diamond substrates a homo-epitaxial CVD diamond film was grown on top of both the implanted and unimplanted regions of the substrate. Raman analysis of the film grown on top of the implanted region revealed it to be under slightly tensile strain as compared to that grown on the unimplanted diamond substrate. The film deposited on the implanted portion of the diamond showed a lower fluorescence background; indicating a lower concentration of incorporated defects. These results suggest that the strain and defects in the diamond substrate material have an important influence on the quality of the homo-epitaxially grown diamond films. 6 refs., 5 figs

  5. Adhesion analysis of polycrystalline diamond films on molybdenum by means of scratch, indentation and sand abrasion testing

    Energy Technology Data Exchange (ETDEWEB)

    Buijnsters, J.G. [Applied Physics, IMM, Department of Applied Physics, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen (Netherlands); Shankar, P. [Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam-603 102 (India); Enckevort, W.J.P. van [Solid State Chemistry, IMM, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen (Netherlands); Schermer, J.J. [Experimental Solid State Physics III, IMM, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen (Netherlands); Meulen, J.J. ter [Applied Physics, IMM, Department of Applied Physics, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen (Netherlands)]. E-mail: htmeulen@sci.kun.nl

    2005-03-01

    Diamond films have been grown by hot-filament chemical vapour deposition (CVD) on molybdenum substrates under different growth conditions. The films grown with increasing substrate temperatures show a higher interconnection of diamond grains, whereas increasing methane concentrations in the 0.5-4.0% range lead to a transition from micro- towards nanocrystalline films. X-ray diffraction analysis shows Mo{sub 2}C interlayer formation. Indentation, scratch and sand erosion tests are used to evaluate the adhesion strength of the diamond films. Using steel ball indenters (diameter 750 {mu}m), indentation and scratch adhesion tests are performed up to final loads of 200 N. Upon indentation, the load values at which diamond film failure such as flaking and detachment is first observed, increase for increasing temperatures in the deposition temperature range of 450-850 deg C. The scratch adhesion tests show critical load values in the range of 16-40 N normal load for films grown for 4 h. In contrast, diamond films grown for 24 h at a methane concentration of 0.5% do not show any failure at all upon scratching up to 75 N. Film failure upon indenting and scratching is also found to decrease for increasing methane concentration in the CVD gas mixture. The sand abrasion tests show significant differences in coating failure for films grown at varying CH{sub 4}/H{sub 2} ratios. In contrast to the other tests, here best coating performance is observed for the films deposited with a methane concentration of 4%.

  6. The study of Zn–Co alloy coatings electrochemically deposited by pulse current

    Directory of Open Access Journals (Sweden)

    Tomić Milorad V.

    2012-01-01

    Full Text Available The electrochemical deposition by pulse current of Zn-Co alloy coatings on steel was examined, with the aim to find out whether pulse plating could produce alloys that could offer a better corrosion protection. The influence of on-time and the average current density on the cathodic current efficiency, coating morphology, surface roughness and corrosion stability in 3% NaCl was examined. At the same Ton/Toff ratio the current efficiency was insignificantly smaller for deposition at higher average current density. It was shown that, depending on the on-time, pulse plating could produce more homogenous alloy coatings with finer morphology, as compared to deposits obtained by direct current. The surface roughness was the greatest for Zn-Co alloy coatings deposited with direct current, as compared with alloy coatings deposited with pulse current, for both examined average current densities. It was also shown that Zn-Co alloy coatings deposited by pulse current could increase the corrosion stability of Zn-Co alloy coatings on steel. Namely, alloy coatings deposited with pulse current showed higher corrosion stability, as compared with alloy coatings deposited with direct current, for almost all examined cathodic times, Ton. Alloy coatings deposited at higher average current density showed greater corrosion stability as compared with coatings deposited by pulse current at smaller average current density. It was shown that deposits obtained with pulse current and cathodic time of 10 ms had the poorest corrosion stability, for both investigated average deposition current density. Among all investigated alloy coatings the highest corrosion stability was obtained for Zn-Co alloy coatings deposited with pulsed current at higher average current density (jav = 4 A dm-2.

  7. Protective silicon coating for nanodiamonds using atomic layer deposition

    International Nuclear Information System (INIS)

    Lu, J.; Wang, Y.H.; Zang, J.B.; Li, Y.N.

    2007-01-01

    Ultrathin silicon coating was deposited on nanodiamonds using atomic layer deposition (ALD) from gaseous monosilane (SiH 4 ). The coating was performed by sequential reaction of SiH 4 saturated adsorption and in situ decomposition. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were utilized to investigate the structural and morphological properties of the coating. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to compare the thermal stability of nanodiamonds before and after silicon coating. The results confirmed that the deposited cubic phase silicon coating was even and continuous. The protective silicon coating could effectively improve the oxidation resistance of nanodiamonds in air flow, which facilitates the applications of nanodiamonds that are commonly hampered by their poor thermal stability

  8. Protective silicon coating for nanodiamonds using atomic layer deposition

    Energy Technology Data Exchange (ETDEWEB)

    Lu, J. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, Hebei 066004 (China); College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei 066004 (China); Wang, Y.H. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, Hebei 066004 (China); College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei 066004 (China); Zang, J.B. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, Hebei 066004 (China) and College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei 066004 (China)]. E-mail: diamondzjb@163.com; Li, Y.N. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao, Hebei 066004 (China); College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei 066004 (China)

    2007-01-30

    Ultrathin silicon coating was deposited on nanodiamonds using atomic layer deposition (ALD) from gaseous monosilane (SiH{sub 4}). The coating was performed by sequential reaction of SiH{sub 4} saturated adsorption and in situ decomposition. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were utilized to investigate the structural and morphological properties of the coating. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to compare the thermal stability of nanodiamonds before and after silicon coating. The results confirmed that the deposited cubic phase silicon coating was even and continuous. The protective silicon coating could effectively improve the oxidation resistance of nanodiamonds in air flow, which facilitates the applications of nanodiamonds that are commonly hampered by their poor thermal stability.

  9. Diamond anvil cells using boron-doped diamond electrodes covered with undoped diamond insulating layer

    Science.gov (United States)

    Matsumoto, Ryo; Yamashita, Aichi; Hara, Hiroshi; Irifune, Tetsuo; Adachi, Shintaro; Takeya, Hiroyuki; Takano, Yoshihiko

    2018-05-01

    Diamond anvil cells using boron-doped metallic diamond electrodes covered with undoped diamond insulating layers have been developed for electrical transport measurements under high pressure. These designed diamonds were grown on a bottom diamond anvil via a nanofabrication process combining microwave plasma-assisted chemical vapor deposition and electron beam lithography. The resistance measurements of a high-quality FeSe superconducting single crystal under high pressure were successfully demonstrated by just putting the sample and gasket on the bottom diamond anvil directly. The superconducting transition temperature of the FeSe single crystal was increased to up to 43 K by applying uniaxial-like pressure.

  10. Microstructure and mechanical properties of diamond films on titanium-aluminum-vanadium alloy

    Science.gov (United States)

    Catledge, Shane Aaron

    The primary focus of this dissertation is the investigation of the processing-structure-property relationships of diamond films deposited on Ti-6Al-4V alloy by microwave plasma chemical vapor deposition (MPCVD). By depositing a well-adhered protective layer of diamond on an alloy component, its hardness, wear-resistance, performance, and overall lifetime could be significantly increased. However, due to the large thermal expansion mismatch between the diamond film and metal (and the corresponding residual stress induced in the film), film adhesion is typically unsatisfactory and often results in immediate delamination after processing. Therefore, it is a major goal of this research to improve adhesion of the diamond film to the alloy substrate. Through the use of innovative processing techniques involving MPCVD deposition conditions and methane (CH4), nitrogen (N2), and hydrogen (H2) chemistry, we have achieved diamond films which consistently adhere to the alloy substrate. In addition, we have discovered that, with the appropriate choice of deposition conditions, the film structure can be tailored to range from highly crystalline, well-faceted diamond to nanocrystalline diamond with extremely low surface roughness (as low as 27 nm). The relationship between processing and structure was studied using in-situ optical emission spectroscopy, micro-Raman spectroscopy, surface profilometry, glancing-angle x-ray diffraction, and scanning electron microscopy. We observe that when nitrogen is added to the H2/CH4 feedgas mixture, a carbon-nitrogen (CN) emission band arises and its relative abundance to the carbon dimer (C2) gas species is shown to have a pronounced influence on the diamond film structure. By appropriate choice of deposition chemistry and conditions, we can tailor the diamond film structure and its corresponding properties. The mechanical properties of interest in this thesis are those relating to the integrity of the film/substrate interface, as well as the

  11. Influence of deposition rate on the properties of tin coatings deposited on tool steels using arc method

    International Nuclear Information System (INIS)

    Akhtar, P.; Abbas, M.

    2007-01-01

    Titanium nitride (TiN) widely used as hard coating material, was coated on tool steels, namely on high-speed steel (HSS) and D2 tool steel by physical vapour deposition method. The study concentrated on cathodic arc physical vapour deposition (CAPVD), a technique used for the deposition of hard coatings for tooling applications, and which has many advantages. The main drawback of this technique, however, is the formation of macrodroplets (MD's) during deposition, resulting in films with rougher morphology. Various standard characterization techniques and equipment, such as electron microscopy, atomic force microscopy, hardness testing machine, scratch tester and pin-on-disc machine, were used to analyze and quantify the following properties and parameters, surface morphology, thickness, hardness, adhesion and coefficient of friction (COF) of the deposited coatings. Surface morphology revealed that the MD's produced during the etching stage, protruded through the thin film, resulting in film with deteriorated surface features. Both coating thickness and indentation loads influenced the hardness of the deposited coatings. The coatings deposited on HSS exhibit better adhesion compared to those on D2 tool steel. Standard deviation indicates that the coating deposited with thickness around 6.7 macro m showed the most stable trend of COF versus sliding distance. (author)

  12. A methodological toolkit for field assessments of artisanally mined alluvial diamond deposits

    Science.gov (United States)

    Chirico, Peter G.; Malpeli, Katherine C.

    2014-01-01

    This toolkit provides a standardized checklist of critical issues relevant to artisanal mining-related field research. An integrated sociophysical geographic approach to collecting data at artisanal mine sites is outlined. The implementation and results of a multistakeholder approach to data collection, carried out in the assessment of Guinea’s artisanally mined diamond deposits, also are summarized. This toolkit, based on recent and successful field campaigns in West Africa, has been developed as a reference document to assist other government agencies or organizations in collecting the data necessary for artisanal diamond mining or similar natural resource assessments.

  13. CVD diamond substrates for electronic devices

    International Nuclear Information System (INIS)

    Holzer, H.

    1996-03-01

    In this study the applicability of chemical vapor deposition (CVD) diamond as a material for heat spreaders was investigated. Economical evaluations on the production of heat spreaders were also performed. For the diamond synthesis the hot-filament and microwave method were used respectively. The deposition parameters were varied in a way that free standing diamond layers with a thickness of 80 to 750 microns and different qualities were obtained. The influence of the deposition parameters on the relevant film properties was investigated and discussed. With both the hot-filament and microwave method it was possible to deposit diamond layers having a thermal conductivity exceeding 1200 W/mK and therefore to reach the quality level for commercial uses. The electrical resistivity was greater than 10 12 Ωcm. The investigation of the optical properties was done by Raman-, IR- and cathodoluminescence spectroscopy. Because of future applications of diamond-aluminium nitride composites as highly efficient heat spreaders diamond deposition an AIN was investigated. An improved substrate pretreatment prior to diamond deposition showed promising results for better performance of such composite heat spreaders. Both free standing layers and diamond-AIN composites could be cut by a CO2 Laser in Order to get an exact size geometry. A reduction of the diamond surface roughness was achieved by etching with manganese powder or cerium. (author)

  14. Dielectric coatings on metal substrates

    International Nuclear Information System (INIS)

    Glaros, S.S.; Baker, P.; Milam, D.

    1976-01-01

    Large aperture, beryllium substrate-based mirrors have been used to focus high intensity pulsed laser beams. Finished surfaces have high reflectivity, low wavefront distortion, and high laser damage thresholds. This paper describes the development of a series of metallic coatings, surface finishing techniques, and dielectric overcoatings to meet specified performance requirements. Beryllium substrates were coated with copper, diamond-machined to within 5 micro-inches to final contour, nickel plated, and abrasively figured to final contour. Bond strengths for several bonding processes are presented. Dielectric overcoatings were deposited on finished multimetallic substrates to increase both reflectivity and the damage thresholds. Coatings were deposited using both high and low temperature processes which induce varying stresses in the finished coating substrate system. Data are presented to show the evolution of wavefront distortion, reflectivity, and damage thresholds throughout the many steps involved in fabrication

  15. Influence of deposition parameters on the refractive index and growth rate of diamond-like carbon films

    International Nuclear Information System (INIS)

    Zhang, G.F.; Zheng, X.; Guo, L.J.; Liu, Z.T.; Xiu, N.K.

    1994-01-01

    In order to use diamond-like carbon (DLC) films as protective and antireflection coatings for IR optical materials exposed to hostile environments, an investigation has been systematically conducted on the influence of the deposition parameters on the refractive index and growth rate of DLC films, which are two of the most important parameters in evaluating optical characteristics of antireflection coatings. The experimental results show that both the refractive index and growth rate of DLC films depend strongly on the negative d.c. bias voltage. The refractive index increases with increasing bias voltage and decreases with increasing partial pressure of the hydrocarbon gas and total flow rate of the mixture. The growth rate increases greatly when the bias voltage is larger than a threshold value. The various parameters which influence the structure and properties of DLC films are interrelated. Fourier transform IR spectroscopy results show that the strength of the C-H stretching absorption band in the range 3300-2850 cm -1 is gradually weakened with increasing negative bias voltage and argon concentration. High energy bombardment of the growing film plays an important role in the structure and hence the properties of DLC films. (orig.)

  16. Influence of load on the dry frictional performance of alkyl acrylate copolymer elastomers coated with diamond-like carbon films

    NARCIS (Netherlands)

    Martinez, D. Martinez; Nohava, Jiri; De Hosson, J. Th. M.

    2015-01-01

    In this work, the influence of applied load on the frictional behavior of alkyl acrylate copolymer elastomers coated with diamond- like carbon films is studied at dry conditions. The performance of two coatings with very different microstructure (patched vs. continuous film) is compared with the

  17. Effect of annealing on field emission properties of nanodiamond coating

    International Nuclear Information System (INIS)

    Zhai, C.X.; Yun, J.N.; Zhao, L.L.; Zhang, Z.Y.; Wang, X.W.; Chen, Y.Y.

    2011-01-01

    Field electron emission of detonation nanodiamond (ND) coated on a titanium substrate by electrophoretic deposition is investigated. It is found that thermal annealing can significantly improve the field emission properties of the ND layer, which can be mainly attributed to the formation of the TiC phase between diamond and Ti. The first-principles calculated results show that the formation of transition layers can lower the interface barrier and enhance the field electron emission of ND coating. Besides, the transformation of diamond to graphite after annealing has been revealed by Raman spectra. This transformation also benefits the electron emission enhancement.

  18. Effect of annealing on field emission properties of nanodiamond coating

    Energy Technology Data Exchange (ETDEWEB)

    Zhai, C.X., E-mail: zhaicatty@126.co [School of Information Science and Technology, Northwest University, Xi' an 710127, Shaanxi (China); Yun, J.N.; Zhao, L.L.; Zhang, Z.Y.; Wang, X.W.; Chen, Y.Y. [School of Information Science and Technology, Northwest University, Xi' an 710127, Shaanxi (China)

    2011-03-01

    Field electron emission of detonation nanodiamond (ND) coated on a titanium substrate by electrophoretic deposition is investigated. It is found that thermal annealing can significantly improve the field emission properties of the ND layer, which can be mainly attributed to the formation of the TiC phase between diamond and Ti. The first-principles calculated results show that the formation of transition layers can lower the interface barrier and enhance the field electron emission of ND coating. Besides, the transformation of diamond to graphite after annealing has been revealed by Raman spectra. This transformation also benefits the electron emission enhancement.

  19. Chemical vapor deposition diamond based multilayered radiation detector: Physical analysis of detection properties

    International Nuclear Information System (INIS)

    Almaviva, S.; Marinelli, Marco; Milani, E.; Prestopino, G.; Tucciarone, A.; Verona, C.; Verona-Rinati, G.; Angelone, M.; Pillon, M.; Dolbnya, I.; Sawhney, K.; Tartoni, N.

    2010-01-01

    Recently, solid state photovoltaic Schottky diodes, able to detect ionizing radiation, in particular, x-ray and ultraviolet radiation, have been developed at the University of Rome 'Tor Vergata'. We report on a physical and electrical properties analysis of the device and a detailed study of its detection capabilities as determined by its electrical properties. The design of the device is based on a metal/nominally intrinsic/p-type diamond layered structure obtained by microwave plasma chemical vapor deposition of homoepitaxial single crystal diamond followed by thermal evaporation of a metallic contact. The device can operate in an unbiased mode by using the built-in potential arising from the electrode-diamond junction. We compare the expected response of the device to photons of various energies calculated through Monte Carlo simulation with experimental data collected in a well controlled experimental setup i.e., monochromatic high flux x-ray beams from 6 to 20 keV, available at the Diamond Light Source synchrotron in Harwell (U.K.).

  20. Workshop on diamond and diamond-like-carbon films for the transportation industry

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, F.A.; Moores, D.K. [eds.

    1993-01-01

    Applications exist in advanced transportation systems as well as in manufacturing processes that would benefit from superior tribological properties of diamond, diamond-like-carbon and cubic boron nitride coatings. Their superior hardness make them ideal candidates as protective coatings to reduce adhesive, abrasive and erosive wear in advanced diesel engines, gas turbines and spark-ignited engines and in machining and manufacturing tools as well. The high thermal conductivity of diamond also makes it desirable for thermal management not only in tribological applications but also in high-power electronic devices and possibly large braking systems. A workshop has been recently held at Argonne National Laboratory entitled ``Diamond and Diamond-Like-Carbon Films for Transportation Applications`` which was attended by 85 scientists and engineers including top people involved in the basic technology of these films and also representatives from many US industrial companies. A working group on applications endorsed 18 different applications for these films in the transportation area alone. Separate abstracts have been prepared.

  1. Adhesion of staphylococcal and Caco-2 cells on diamond-like carbon polymer hybrid coating.

    Science.gov (United States)

    Kinnari, Teemu J; Soininen, Antti; Esteban, Jaime; Zamora, Nieves; Alakoski, Esa; Kouri, Vesa-Petteri; Lappalainen, Reijo; Konttinen, Yrjö T; Gomez-Barrena, Enrique; Tiainen, Veli-Matti

    2008-09-01

    Staphylococci cause the majority of the nosocomial implant-related infections initiated by adhesion of planktonic bacteria to the implant surface. It was hypothesized that plasma accelerating filtered pulsed arc discharge method enables combination of the advantageous properties of diamond with the antisoiling properties of polymers. Diamond-like carbon polytetrafluoroethylene hybrid (DLC-PTFE-h) coating was produced. The adhesion of S. aureus ATCC 25923 (10(8) colony-forming units/mL) to surfaces diminished from 2.32%, 2.35%, and 2.57% of high quality DLC, titanium, and oxidized silicon, respectively, to 1.93% of DLC-PTFE-h. For S. epidermidis ATCC 35984 the corresponding figures were 3.90%, 3.32%, 3.47%, and 2.57%. Differences in bacterial adhesion between recombinant DLC-PTFE-h and other materials were statistically significant (p DLC-PTFE-h as to DLC, titanium, or silicon, which were all in the MTT test found to be cytocompatible. DLC-PTFE-h coating can be used to modify the surface properties of any surgical implants and is an unfavorable substrate for staphylococcal cells, but compatible with human Caco-2 cells. DLC-PTFE-h coating may help in the combat against Staphylococcus-related implant infections which usually require both antibiotics and surgical removal of the implant for cure.

  2. Characterization of diamond thin films deposited by a CO{sub 2} laser-assisted combustion-flame method

    Energy Technology Data Exchange (ETDEWEB)

    McKindra, Travis, E-mail: mckindra@mst.edu [Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); O' Keefe, Matthew J. [Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Xie Zhiqiang; Lu Yongfeng [Department of Electrical Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588 (United States)

    2010-06-15

    Diamond thin films were deposited by a CO{sub 2} laser-assisted O{sub 2}/C{sub 2}H{sub 2}/C{sub 2}H{sub 4} combustion-flame process. The effect of the deposition parameters, in particular the laser wavelength and power, on the film surface morphology, microstructure and phases present was the primary focus of the work. The laser power was set at 100, 400 and 800 W while the wavelength was varied and set at 10.591 {mu}m in the untuned condition and set at 10.532 {mu}m to resonantly match the CH{sub 2}-wagging vibrational mode of the C{sub 2}H{sub 4} molecule when in the tuned condition. When the laser was coupled to the combustion flame during deposition the diamond film growth was enhanced as the lateral grain size increased from 1 {mu}m to greater than 5 {mu}m. The greatest increase in grain size occurred when the wavelength was in the tuned condition. Scanning transmission electron microscopy images from focused-ion beam cross-sectioned samples revealed a sub-layer of smaller grains less than 1 {mu}m in size near the substrate surface at the lower laser powers and untuned wavelength. X-ray diffraction results showed a more intense Diamond (111) peak as the laser power increased from 100 to 800 W for the films deposited with the tuned laser wavelength. Micro-Raman spectra showed a diamond peak nearly twice as intense from the films with the tuned laser wavelength.

  3. Memory effect in the deposition of C20 fullerenes on a diamond surface

    Science.gov (United States)

    Du, A. J.; Pan, Z. Y.; Ho, Y. K.; Huang, Z.; Zhang, Z. X.

    2002-07-01

    In this paper, the deposition of C20 fullerenes on a diamond (001)-(2×1) surface and the fabrication of C20 thin film at 100 K were investigated by a molecular dynamics (MD) simulation using the many-body Brenner bond order potential. First, we found that the collision dynamic of a single C20 fullerene on a diamond surface was strongly dependent on its impact energy. Within the energy range 10-45 eV, the C20 fullerene chemisorbed on the surface retained its free cage structure. This is consistent with the experimental observation, where it was called the memory effect in ``C20-type'' films [P. Melion et al., Int. J. Mod. B 9, 339 (1995); P. Milani et al., Cluster Beam Synthesis of Nanostructured Materials (Springer, Berlin, 1999)]. Next, more than one hundred C20 (10-25 eV) were deposited one after the other onto the surface. The initial growth stage of C20 thin film was observed to be in the three-dimensional island mode. The randomly deposited C20 fullerenes stacked on diamond surface and acted as building blocks forming a polymerlike structure. The assembled film was also highly porous due to cluster-cluster interaction. The bond angle distribution and the neighbor-atom-number distribution of the film presented a well-defined local order, which is of sp3 hybridization character, the same as that of a free C20 cage. These simulation results are again in good agreement with the experimental observation. Finally, the deposited C20 film showed high stability even when the temperature was raised up to 1500 K.

  4. Ion implantation and diamond-like coatings of aluminum alloys

    Science.gov (United States)

    Malaczynski, G. W.; Hamdi, A. H.; Elmoursi, A. A.; Qiu, X.

    1997-04-01

    In an attempt to increase the wear resistance of some key automotive components, General Motors Research and Development Center initiated a study to determine the potential of surface modification as a means of improving the tribological properties of automotive parts, and to investigate the feasibility of mass producing such parts. This paper describes the plasma immersion ion implantation system that was designed for the study of various options for surface treatment, and it discusses bench testing procedures used for evaluating the surface-treated samples. In particular, both tribological and microstructural analyses are discussed for nitrogen implants and diamond-like hydrocarbon coatings of some aluminum alloys.

  5. Microcontact printing of monodiamond nanoparticles: an effective route to patterned diamond structure fabrication.

    Science.gov (United States)

    Zhuang, Hao; Song, Bo; Staedler, Thorsten; Jiang, Xin

    2011-10-04

    By combining microcontact printing with a nanodiamond seeding technique, a precise micrometer-sized chemical vapor deposition (CVD) diamond pattern have been obtained. On the basis of the guidance of basic theoretical calculations, monodisperse detonation nanodiamonds (DNDs) were chosen as an "ink" material and oxidized poly(dimethylsiloxane) (PDMS) was selected to serve as a stamp because it features a higher interaction energy with the DNDs compared to that of the original PDMS. The adsorption kinetics shows an approximately exponential law with a maximum surface DND density of 3.4 × 10(10) cm(-2) after 20 min. To achieve a high transfer ratio of DNDs from the PDMS stamp to a silicon surface, a thin layer of poly(methyl methacrylate) (PMMA) was spin coated onto the substrates. A microwave plasma chemical vapor deposition system was used to synthesize the CVD diamond on the seeded substrate areas. Precise diamond patterns with a low expansion ratio (3.6%) were successfully prepared after 1.5 h of deposition. Further increases in the deposition time typically lead to a high expansion rate (∼0.8 μm/h). The general pattern shape, however, did not show any significant change. Compared with conventional diamond pattern deposition methods, the technique described here offers the advantages of being simple, inexpensive, damage-free, and highly compatible, rendering it attractive for a broad variety of industrial applications. © 2011 American Chemical Society

  6. The study and the realization of radiation detectors made from polycrystalline diamond films grown by microwave plasma enhanced chemical vapour deposition technique

    International Nuclear Information System (INIS)

    Jany, Ch.

    1998-01-01

    The aim of this work was to develop radiation detectors made from polycrystalline diamond films grown by microwave plasma enhanced chemical vapour deposition technique. The influence of surface treatments, contact technology and diamond growth parameters on the diamond detectors characteristics was investigated in order to optimise the detector response to alpha particles. The first part of the study focused on the electrical behaviour of as-deposited diamond surface, showing a p type conduction and its influence on the leakage current of the device. A surface preparation process was established in order to reduce the leakage current of the device by surface dehydrogenation using an oxidising step. Several methods to form and treat electrical contacts were also investigated showing that the collection efficiency of the device decreases after contact annealing. In the second part, we reported the influence of the diamond deposition parameters on the characteristics of the detectors. The increase of the deposition temperature and/or methane concentration was shown to lead η to decrease. In contrast, η was found to increase with the micro-wave power. The evolution of the diamond detector characteristics results from the variation in sp 2 phases incorporation and in the crystallography quality of the films. These defects increase the leakage current and reduce the carrier mobility and lifetime. Measurements carried out on detectors with different thicknesses showed that the physical properties varies along the growth direction, improving with the film thickness. Finally, the addition of nitrogen (> 10 ppm) in the gas mixture during diamond deposition was found to strongly reduce the collection efficiency of the detectors. To conclude the study, we fabricated and characterised diamond devices which were used for thermal neutron detection and for the intensity and shape measurement of VUV and soft X-ray pulses. (author)

  7. Coating material innovation in conjunction with optimized deposition technologies

    International Nuclear Information System (INIS)

    Stolze, M.; Leitner, K.

    2009-01-01

    Concentrating on physical vapour deposition methods several examples of recently developed coating materials for optical applications were studied for film deposition with optimized coating technologies: mixed evaporation materials for ion assisted deposition with modern plasma ion sources, planar metal and oxide sputter targets for Direct Current (DC) and Mid-Frequency (MF) pulsed sputter deposition and planar and rotatable sputter targets of transparent conductive oxides (TCO) for large-area sputter deposition. Films from specially designed titania based mixed evaporation materials deposited with new plasma ion sources and possible operation with pure oxygen showed extended ranges of the ratio between refractive index and structural film stress, hence there is an increased potential for the reduction of the total coating stress in High-Low alternating stacks and for coating plastics. DC and MF-pulsed sputtering of niobium metal and suboxide targets for optical coatings yielded essential benefits of the suboxide targets in a range of practical coating conditions (for absent in-situ post-oxidation ability): higher refractive index and deposition rate, better reproducibility and easier process control, and the potential for co-deposition of several targets. Technological progress in the manufacture of rotatable indium tin oxide (ITO) targets with regard to higher wall-thickness and density was shown to be reflected in higher material stock and coater up-time, economical deposition rates and stable process behaviour. Both for the rotatable ITO targets and higher-dense aluminum-doped zinc oxide (AZO) planar targets values of film transmittance and resistivity were in the range of the best values industrially achieved for films from the respective planar targets. The results for the rotatable ITO and planar AZO targets point to equally optimized process and film properties for the optimized rotatable AZO targets currently in testing

  8. Nanostructured titanium/diamond-like carbon multilayer films: deposition, characterization, and applications.

    Science.gov (United States)

    Dwivedi, Neeraj; Kumar, Sushil; Malik, Hitendra K

    2011-11-01

    Titanium/diamond-like carbon multilayer (TDML) films were deposited using a hybrid system combining radio frequency (RF)-sputtering and RF-plasma enhanced chemical vapor deposition (PECVD) techniques under a varied number of Ti/diamond-like carbon (DLC) bilayers from 1 to 4, at high base pressure of 1 × 10(-3) Torr. The multilayer approach was used to create unique structures such as nanospheres and nanorods in TDML films, which is confirmed by scanning electron microscopy (SEM) analysis and explained by a hypothetical model. Surface composition was evaluated by X-ray photoelectron spectroscopy (XPS), whereas energy dispersive X-ray analysis (EDAX) and time-of-flight secondary ion mass spectrometer (ToF-SIMS) measurements were performed to investigate the bulk composition. X-ray diffraction (XRD) was used to evaluate the phase and crystallinity of the deposited TDML films. Residual stress in these films was found to be significantly low. These TDML films were found to have excellent nanomechanical properties with maximum hardness of 41.2 GPa. In addition, various nanomechanical parameters were calculated and correlated with each other. Owing to metallic interfacial layer of Ti in multilayer films, the optical properties, electrical properties, and photoluminescence were improved significantly. Due to versatile nanomechanical properties and biocompatibility of DLC and DLC based films, these TDML films may also find applications in biomedical science.

  9. Gas Permeation, Mechanical Behavior and Cytocompatibility of Ultrathin Pure and Doped Diamond-Like Carbon and Silicon Oxide Films

    Directory of Open Access Journals (Sweden)

    Juergen M. Lackner

    2013-12-01

    Full Text Available Protective ultra-thin barrier films gather increasing economic interest for controlling permeation and diffusion from the biological surrounding in implanted sensor and electronic devices in future medicine. Thus, the aim of this work was a benchmarking of the mechanical oxygen permeation barrier, cytocompatibility, and microbiological properties of inorganic ~25 nm thin films, deposited by vacuum deposition techniques on 50 µm thin polyetheretherketone (PEEK foils. Plasma-activated chemical vapor deposition (direct deposition from an ion source was applied to deposit pure and nitrogen doped diamond-like carbon films, while physical vapor deposition (magnetron sputtering in pulsed DC mode was used for the formation of silicon as well as titanium doped diamond-like carbon films. Silicon oxide films were deposited by radio frequency magnetron sputtering. The results indicate a strong influence of nanoporosity on the oxygen transmission rate for all coating types, while the low content of microporosity (particulates, etc. is shown to be of lesser importance. Due to the low thickness of the foil substrates, being easily bent, the toughness as a measure of tendency to film fracture together with the elasticity index of the thin films influence the oxygen barrier. All investigated coatings are non-pyrogenic, cause no cytotoxic effects and do not influence bacterial growth.

  10. CMAS Interactions with Advanced Environmental Barrier Coatings Deposited via Plasma Spray- Physical Vapor Deposition

    Science.gov (United States)

    Harder, B. J.; Wiesner, V. L.; Zhu, D.; Johnson, N. S.

    2017-01-01

    Materials for advanced turbine engines are expected to have temperature capabilities in the range of 1370-1500C. At these temperatures the ingestion of sand and dust particulate can result in the formation of corrosive glass deposits referred to as CMAS. The presence of this glass can both thermomechanically and thermochemically significantly degrade protective coatings on metallic and ceramic components. Plasma Spray- Physical Vapor Deposition (PS-PVD) was used to deposit advanced environmental barrier coating (EBC) systems for investigation on their interaction with CMAS compositions. Coatings were exposed to CMAS and furnace tested in air from 1 to 50 hours at temperatures ranging from 1200-1500C. Coating composition and crystal structure were tracked with X-ray diffraction and microstructure with electron microscopy.

  11. Comparative study of dlc coatings by pvd against cvd technique on textile dents

    International Nuclear Information System (INIS)

    Malik, M.; Alam, S.; Iftikhar, F.

    2007-01-01

    Diamond like Carbon (DLC) film is a hard amorphous carbon hydride film formed by Physical or Chemical vapor deposition (PVD or CVD) techniques. Due to its unique properties especially high hardness, lower coefficient of friction and lubricious nature, these coatings are not only used to extend the life of cutting tools but also for non cutting applications such as for forming dies, molds and on many functional parts of textile. In the present work two techniques were employed i.e. PVD and CVD for deposition of diamond like carbon film on textile dents. These dents are used as thread guider in high speed weaving machine. The measurement of coating thickness, adhesion, hardness and roughness values indicates that overall properties of DLC coating developed by PVD LARC technology reduces abrasion and increases the workability and durability of textile dents as well as suppress the need of lubricants. (author)

  12. Electrochemical Sensor Coating Based on Electrophoretic Deposition of Au-Doped Self-Assembled Nanoparticles.

    Science.gov (United States)

    Zhang, Rongli; Zhu, Ye; Huang, Jing; Xu, Sheng; Luo, Jing; Liu, Xiaoya

    2018-02-14

    The electrophoretic deposition (EPD) of self-assembled nanoparticles (NPs) on the surface of an electrode is a new strategy for preparing sensor coating. By simply changing the deposition conditions, the electrochemical response for an analyte of deposited NPs-based coating can be controlled. This advantage can decrease the difference between different batches of sensor coating and ensure the reproducibility of each sensor. This work investigated the effects of deposition conditions (including deposition voltage, pH value of suspension, and deposition time) on the structure and the electrochemical response for l-tryptophan of sensor coating formed from Au-doped poly(sodium γ-glutamate) with pendant dopamine units nanohybrids (Au/γ-PGA-DA NBs) via the EPD method. The structure and thickness of the deposited sensor coating were measured by atomic force microscopy, which demonstrated that the structure and thickness of coating can be affected by the deposition voltage, the pH value of the suspension, and the deposition time. The responsive current for l-tryptophan of the deposited sensor coating were measured by differential pulse voltammetry, which showed that the responsive current value was affected by the structure and thickness of the deposited coating. These arguments suggested that a rich design-space for tuning the electrochemical response for analyte and a source of variability in the structure of sensor coating can be provided by the deposition conditions. When Au/γ-PGA-DA NBs were deposited on the electrode surface and formed a continuous coating with particle morphology and thinner thickness, the deposited sensor coating exhibited optimal electrochemical response for l-tryptophan.

  13. Development of reliable diamond window for EC launcher on fusion reactors

    International Nuclear Information System (INIS)

    Takahashi, K.; Illy, S.; Heidinger, R.; Kasugai, A.; Minami, R.; Sakamoto, K.; Thumm, M.; Imai, T.

    2005-01-01

    In order to avoid a possible accidental event of a diamond window, i.e. a leakage of cooling water into vacuum, a new diamond window with a copper (Cu)-coated edge was developed. The 0.5 mm thick Cu-coating completely covers the window disk edge and aluminum braze, between the diamond disk edge and the inconel cuffs cooled by water. Corrosion of the aluminum braze can also be prevented by the Cu-coating. A 170 GHz high power RF transmission experiment, which was indicative for a MW-level transmission, was carried out to investigate the cooling capability of the Cu-coated window. RF power/pulse length 55 kW/3.5 s and 120 kW/3 s, were transmitted through the window without any problem. Temperature increase of 50 and 100 o C were obtained, respectively. The results agree with thermal calculations with loss tangent 8.5 x 10 -4 and thermal conductivity 1.9 kW/(m K) of the diamond. Thermal and stress analysis show that no serious stress between the diamond disk and the Cu-coating is established. It concludes that a diamond window with Cu-coated edge water-cooling is capable of MW-level transmission and that the Cu-coating improves the reliability of the diamond window

  14. Tribological behavior of W-DLC coated rubber seals

    NARCIS (Netherlands)

    Pei, Y.T.; Bui, X.L.; Zhou, X.B.; Hosson, J.Th.M. De

    2008-01-01

    Tungsten-containing diamond-like carbon (W-DLC) coatings have been deposited on FKM (fluorocarbon) and HNBR (hydrogenated nitrile butadiene) rubbers via unbalanced magnetron reactive sputtering from a WC target in a C2H2/Ar plasma. The surface morphology and fracture cross sections of uncoated and

  15. Influence of coil current modulation on polycrystalline diamond film deposition by irradiation of Ar/CH4/H2 inductively coupled thermal plasmas

    Science.gov (United States)

    Betsuin, Toshiki; Tanaka, Yasunori; Arai, T.; Uesugi, Y.; Ishijima, T.

    2018-03-01

    This paper describes the application of an Ar/CH4/H2 inductively coupled thermal plasma with and without coil current modulation to synthesise diamond films. Induction thermal plasma with coil current modulation is referred to as modulated induction thermal plasma (M-ITP), while that without modulation is referred to as non-modulated ITP (NM-ITP). First, spectroscopic observations of NM-ITP and M-ITP with different modulation waveforms were made to estimate the composition in flux from the thermal plasma by measuring the time evolution in the spectral intensity from the species. Secondly, we studied polycrystalline diamond film deposition tests on a Si substrate, and we studied monocrystalline diamond film growth tests using the irradiation of NM-ITP and M-ITP. From these tests, diamond nucleation effects by M-ITP were found. Finally, following the irradiation results, we attempted to use a time-series irradiation of M-ITP and NM-ITP for polycrystalline diamond film deposition on a Si substrate. The results indicated that numerous larger diamond particles were deposited with a high population density on the Si substrate by time-series irradiation.

  16. Flexible camphor diamond-like carbon coating on polyurethane to prevent Candida albicans biofilm growth.

    Science.gov (United States)

    Santos, Thaisa B; Vieira, Angela A; Paula, Luciana O; Santos, Everton D; Radi, Polyana A; Khouri, Sônia; Maciel, Homero S; Pessoa, Rodrigo S; Vieira, Lucia

    2017-04-01

    Camphor was incorporated in diamond-like carbon (DLC) films to prevent the Candida albicans yeasts fouling on polyurethane substrates, which is a material commonly used for catheter manufacturing. The camphor:DLC and DLC film for this investigation was produced by plasma enhanced chemical vapor deposition (PECVD), using an apparatus based on the flash evaporation of organic liquid (hexane) containing diluted camphor for camphor:DLC and hexane/methane, mixture for DLC films. The film was deposited at a low temperature of less than 25°C. We obtained very adherent camphor:DLC and DLC films that accompanied the substrate flexibility without delamination. The adherence of camphor:DLC and DLC films on polyurethane segments were evaluated by scratching test and bending polyurethane segments at 180°. The polyurethane samples, with and without camphor:DLC and DLC films were characterized by Raman spectroscopy, scanning electron microscopy, atomic force microscopy, and optical profilometry. Candida albicans biofilm formation on polyurethane, with and without camphor:DLC and DLC, was assessed. The camphor:DLC and DLC films reduced the biofilm growth by 99.0% and 91.0% of Candida albicans, respectively, compared to bare polyurethane. These results open the doors to studies of functionalized DLC coatings with biofilm inhibition properties used in the production of catheters or other biomedical applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Factors influencing the deposition of hydroxyapatite coating onto hollow glass microspheres

    International Nuclear Information System (INIS)

    Jiao, Yan; Xiao, Gui-Yong; Xu, Wen-Hua; Zhu, Rui-Fu; Lu, Yu-Peng

    2013-01-01

    Hydroxyapatite (HA) and HA coated microcarriers for cell culture and delivery have attracted more attention recently, owing to the rapid progress in the field of tissue engineering. In this research, a dense and uniform HA coating with the thickness of about 2 μm was successfully deposited on hollow glass microspheres (HGM) by biomimetic process. The influences of SBF concentration, immersion time, solid/liquid ratio and activation of HGM on the deposition rate and coating characteristics were discussed. X-ray diffraction (XRD) and Fourier transform infrared spectrum (FTIR) analyses revealed that the deposited HA is poorly crystalline. The thickness of HA coating showed almost no increase after immersion in 1.5SBF for more than 15 days with the solid/liquid ratio of 1:150. At the same time, SBF concentration, solid/liquid ratio and activation treatment played vital roles in the formation of HA coating on HGM. This poorly crystallized HA coated HGM could have potential use as microcarrier for cell culture. Highlights: • HA coatings were deposited on hollow glass microspheres by biomimetic process. • The obtained HA coating was poorly crystalline and carbonated. • The influencing factors of deposition rate and coating characteristics were studied. • The thickness of HA coating showed almost no increase after immersion for 15 days

  18. Hemocompatibility of Inorganic Physical Vapor Deposition (PVD Coatings on Thermoplastic Polyurethane Polymers

    Directory of Open Access Journals (Sweden)

    Daniel Heim

    2012-04-01

    Full Text Available Biocompatibility improvements for blood contacting materials are of increasing interest for implanted devices and interventional tools. The current study focuses on inorganic (titanium, titanium nitride, titanium oxide as well as diamond-like carbon (DLC coating materials on polymer surfaces (thermoplastic polyurethane, deposited by magnetron sputtering und pulsed laser deposition at room temperature. DLC was used pure (a-C:H as well as doped with silicon, titanium, and nitrogen + titanium (a-C:H:Si, a-C:H:Ti, a-C:H:N:Ti. In-vitro testing of the hemocompatibility requires mandatory dynamic test conditions to simulate in-vivo conditions, e.g., realized by a cone-and-plate analyzer. In such tests, titanium- and nitrogen-doped DLC and titanium nitride were found to be optimally anti-thrombotic and better than state-of-the-art polyurethane polymers. This is mainly due to the low tendency to platelet microparticle formation, a high content of remaining platelets in the whole blood after testing and low concentration of platelet activation and aggregation markers. Comparing this result to shear-flow induced cell motility tests with e.g., Dictostelium discoideum cell model organism reveals similar tendencies for the investigated materials.

  19. Hemocompatibility of Inorganic Physical Vapor Deposition (PVD) Coatings on Thermoplastic Polyurethane Polymers.

    Science.gov (United States)

    Lackner, Juergen M; Waldhauser, Wolfgang; Hartmann, Paul; Bruckert, Franz; Weidenhaupt, Marianne; Major, Roman; Sanak, Marek; Wiesinger, Martin; Heim, Daniel

    2012-04-17

    Biocompatibility improvements for blood contacting materials are of increasing interest for implanted devices and interventional tools. The current study focuses on inorganic (titanium, titanium nitride, titanium oxide) as well as diamond-like carbon (DLC) coating materials on polymer surfaces (thermoplastic polyurethane), deposited by magnetron sputtering und pulsed laser deposition at room temperature. DLC was used pure (a-C:H) as well as doped with silicon, titanium, and nitrogen + titanium (a-C:H:Si, a-C:H:Ti, a-C:H:N:Ti). In-vitro testing of the hemocompatibility requires mandatory dynamic test conditions to simulate in-vivo conditions, e.g., realized by a cone-and-plate analyzer. In such tests, titanium- and nitrogen-doped DLC and titanium nitride were found to be optimally anti-thrombotic and better than state-of-the-art polyurethane polymers. This is mainly due to the low tendency to platelet microparticle formation, a high content of remaining platelets in the whole blood after testing and low concentration of platelet activation and aggregation markers. Comparing this result to shear-flow induced cell motility tests with e.g., Dictostelium discoideum cell model organism reveals similar tendencies for the investigated materials.

  20. Characteristics of diamond – like carbon(DLC film deposited by PACVD process

    Directory of Open Access Journals (Sweden)

    Krzysztof Lukaszkowicz

    2016-10-01

    Full Text Available Diamond – like carbon (DLC film is promising materials for many technical and engineering applications. DLC films are used in many different industries for example: in medicine, in electronics, in optics and the automotive industry. They have excellent tribological properties (low friction coefficient, chemical inertness and high mechanical hardness. This paper provides an analysis of the microstructure, mechanical and tribological properties of DLC films. In the study of the coating used several surface sensitive techniques and methods, i.e. High Resolution Transmission Electron Microscopy (HRTEM, Scanning Electron Microscopy (SEM, Raman spectroscopy and tribological tests like ball-on-disc. HRTEM investigation shows an amorphous character of DLC layer. In sliding dry friction conditions the friction coefficient for the investigated elements is set in the range between 0.02-0.03. The investigated coating reveals high wear resistance. The coating demonstrated a good adhesion to the substrate.

  1. Synthesis of thick diamond films by direct current hot-cathode plasma chemical vapour deposition

    CERN Document Server

    Jin Zeng Sun; Bai Yi Zhen; Lu Xian Yi

    2002-01-01

    The method of direct current hot-cathode plasma chemical vapour deposition has been established. A long-time stable glow discharge at large discharge current and high gas pressure has been achieved by using a hot cathode in the temperature range from 1100 degree C to 1500 degree C and non-symmetrical configuration of the poles, in which the diameter of the cathode is larger than that of anode. High-quality thick diamond films, with a diameter of 40-50 mm and thickness of 0.5-4.2 mm, have been synthesized by this method. Transparent thick diamond films were grown over a range of growth rates between 5-10 mu m/h. Most of the thick diamond films have thermal conductivities of 10-12 W/K centre dot cm. The thick diamond films with high thermal conductivity can be used as a heat sink of semiconducting laser diode array and as a heat spreading and isolation substrate of multichip modules. The performance can be obviously improved

  2. Experimental Investigation on Ductile Mode Micro-Milling of ZrO2 Ceramics with Diamond-Coated End Mills

    Directory of Open Access Journals (Sweden)

    Rong Bian

    2018-03-01

    Full Text Available ZrO2 ceramics are currently used in a broad range of industrial applications. However, the machining of post-sintered ZrO2 ceramic is a difficult task, due to its high hardness and brittleness. In this study, micro-milling of ZrO2 with two kinds of diamond-coated end mills has been conducted on a Kern MMP 2522 micro-milling center (Kern Microtechnik GmbH, Eschenlohe, Germany. To achieve a ductile mode machining of ZrO2, the feed per tooth and depth of cut was set in the range of a few micrometers. Cutting force and machined surface roughness have been measured by a Kistler MiniDynamometer (Kistler Group, Winterthur, Switzerland and a Talysurf 120 L profilometer (Taylor Hobson Ltd., Leicester, UK, respectively. Machined surface topography and tool wear have been examined under SEM. Experiment results show that the material can be removed in ductile mode, and mirror quality surface with Ra low as 0.02 μm can be achieved. Curled and smooth chips have been collected and observed. The axial cutting force Fz is always bigger than Fx and Fy, and presents a rising trend with increasing of milling length. Tool wear includes delamination of diamond coating and wear of tungsten carbide substrate. Without the protection of diamond coating, the tungsten carbide substrate was worn out quickly, resulting a change of tool tip geometry.

  3. Plasma immersion ion implantation and deposition of DLC coating for modification of orthodontic magnets

    International Nuclear Information System (INIS)

    Wongsarat, W.; Sarapirom, S.; Aukkaravittayapun, S.; Jotikasthira, D.; Boonyawan, D.; Yu, L.D.

    2012-01-01

    This study was aimed to use the plasma immersion ion implantation and deposition (PIII-D) technique to form diamond-like carbon (DLC) thin films on orthodontic magnets to solve the corrosion problem. To search for the optimal material modification effect, PIII-D conditions including gases, processing time, and pulsing mode were varied. The formation of DLC films was confirmed and characterized with Raman spectra. The intensity of the remnant magnetic field of the magnets and the hardness, adhesion and thickness of the thin films were then measured. A corrosion test was carried out using clinic dental fluid. Improved benefits including a satisfying hardness, adhesion, remnant magnetic strength and corrosion resistance of the DLC coating could be achieved by using a higher interrupting time ratio and shorter processing time.

  4. Plasma immersion ion implantation and deposition of DLC coating for modification of orthodontic magnets

    Energy Technology Data Exchange (ETDEWEB)

    Wongsarat, W. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Sarapirom, S. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); National Metal and Materials Technology Center, 114 Thailand Science Park, Paholyothin Road, Klong 1, Klong Luang, Pathumthani, Bangkok 12120 (Thailand); Aukkaravittayapun, S. [National Metal and Materials Technology Center, 114 Thailand Science Park, Paholyothin Road, Klong 1, Klong Luang, Pathumthani, Bangkok 12120 (Thailand); Jotikasthira, D. [Department of Odontology-Oral Pathology, Faculty of Dentistry, Chiang Mai University, Chiang Mai 50200 (Thailand); Boonyawan, D. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@fnrf.science.cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

    2012-02-01

    This study was aimed to use the plasma immersion ion implantation and deposition (PIII-D) technique to form diamond-like carbon (DLC) thin films on orthodontic magnets to solve the corrosion problem. To search for the optimal material modification effect, PIII-D conditions including gases, processing time, and pulsing mode were varied. The formation of DLC films was confirmed and characterized with Raman spectra. The intensity of the remnant magnetic field of the magnets and the hardness, adhesion and thickness of the thin films were then measured. A corrosion test was carried out using clinic dental fluid. Improved benefits including a satisfying hardness, adhesion, remnant magnetic strength and corrosion resistance of the DLC coating could be achieved by using a higher interrupting time ratio and shorter processing time.

  5. Colloidal spray method for low cost thin coating deposition

    Science.gov (United States)

    Pham, Ai-Quoc; Glass, Robert S.; Lee, Tae H.

    2002-01-01

    A dense or porous coating of material is deposited onto a substrate by forcing a colloidal suspension through an ultrasonic nebulizer and spraying a fine mist of particles in a carrier medium onto a sufficiently heated substrate. The spraying rate is essentially matched to the evaporation rate of the carrier liquid from the substrate to produce a coating that is uniformly distributed over the surface of the substrate. Following deposition to a sufficient coating thickness, a single sintering step may be used to produce a dense ceramic coating. Using this method, coatings ranging in thickness from about one to several hundred microns can be obtained. By using a plurality of compounds in the colloidal suspension, coatings of mixed composition can be obtained. By using a plurality of solutions and separate pumps and a single or multiple ultrasonic nebulizer(s), and varying the individual pumping rates and/or the concentrations of the solutions, a coating of mixed and discontinuously graded (e.g., stepped) or continuously graded layers may be obtained. This method is particularly useful for depositing ceramic coatings. Dense ceramic coating materials on porous substrates are useful in providing improved electrode performance in devices such as high power density solid oxide fuel cells. Dense ceramic coatings obtained by the invention are also useful for gas turbine blade coatings, sensors, steam electrolyzers, etc. The invention has general use in preparation of systems requiring durable and chemically resistant coatings, or coatings having other specific chemical or physical properties.

  6. High Temperature Multilayer Environmental Barrier Coatings Deposited Via Plasma Spray-Physical Vapor Deposition

    Science.gov (United States)

    Harder, Bryan James; Zhu, Dongming; Schmitt, Michael P.; Wolfe, Douglas E.

    2014-01-01

    Si-based ceramic matrix composites (CMCs) require environmental barrier coatings (EBCs) in combustion environments to avoid rapid material loss. Candidate EBC materials have use temperatures only marginally above current technology, but the addition of a columnar oxide topcoat can substantially increase the durability. Plasma Spray-Physical Vapor Deposition (PS-PVD) allows application of these multilayer EBCs in a single process. The PS-PVD technique is a unique method that combines conventional thermal spray and vapor phase methods, allowing for tailoring of thin, dense layers or columnar microstructures by varying deposition conditions. Multilayer coatings were deposited on CMC specimens and assessed for durability under high heat flux and load. Coated samples with surface temperatures ranging from 2400-2700F and 10 ksi loads using the high heat flux laser rigs at NASA Glenn. Coating morphology was characterized in the as-sprayed condition and after thermomechanical loading using electron microscopy and the phase structure was tracked using X-ray diffraction.

  7. Gradient titanium and silver based carbon coatings deposited on AISI316L

    Science.gov (United States)

    Batory, Damian; Reczulska, Malgorzata Czerniak-; Kolodziejczyk, Lukasz; Szymanski, Witold

    2013-06-01

    The constantly growing market for medical implants and devices caused mainly due to a lack of proper attention attached to the physical condition as well as extreme sports and increased elderly population creates the need of new biocompatible biomaterials with controlled bioactivity and certain useful properties. According to many literature reports, regarding the modifications of variety of different biomaterials using the surface engineering techniques and their biological and physicochemical examination results, the most promising material for great spectra of medical applications seem to be carbon layers. Another issue is the interaction between the implant material and surrounding tissue. In particular cases this interface area is directly exposed to air. Abovementioned concern occurs mainly in case of the external fixations, thus they are more vulnerable to infection. Therefore a crucial role has the inhibition of bacterial adhesion that may prevent implant-associated infections, occurrence of other numerous complications and in particular cases rejection of the implant. For this reason additional features of carbon coatings like antibacterial properties seem to be desired and justified. Silver doped diamond-like carbon coatings with different Ag concentrations were prepared by hybrid RF PACVD/MS (Radio Frequency Plasma Assisted Chemical Vapor Deposition/Magnetron Sputtering) deposition technique. Physicochemical parameters like chemical composition, morphology and surface topography, hardness and adhesion were determined. Examined layers showed a uniform distribution of silver in the amorphous DLC matrix, high value of H/E ratio, good adhesion and beneficial topography which make them a perfect material for medical applications e.g. modification of implants for the external fixations.

  8. Deposition and Characterization of HVOF Thermal Sprayed Functionally Graded Coatings Deposited onto a Lightweight Material

    Science.gov (United States)

    Hasan, M.; Stokes, J.; Looney, L.; Hashmi, M. S. J.

    2009-02-01

    There is a significant interest in lightweight materials (like aluminum, magnesium, titanium, and so on) containing a wear resistance coating, in such industries as the automotive industry, to replace heavy components with lighter parts in order to decrease vehicle weight and increase fuel efficiency. Functionally graded coatings, in which the composition, microstructure, and/or properties vary gradually from the bond coat to the top coat, may be applied to lightweight materials, not only to decrease weight, but also to enhance components mechanical properties by ensuring gradual microstructural (changes) together with lower residual stress. In the current work, aluminum/tool-steel functionally graded coatings were deposited onto lightweight aluminum substrates. The graded coatings were then characterized in terms of residual stress and hardness. Results show that residual stress increased with an increase in deposition thickness and a decrease in number of layers. However, the hardness also increased with an increase in deposition thickness and decrease in number of layers. Therefore, an engineer must compromise between the hardness and stress values while designing a functionally graded coating-substrate system.

  9. A diamond-like carbon film for wear protection of steel

    International Nuclear Information System (INIS)

    Harris, S.J.; Weiner, A.M.; Tung, S.C.; Simko, S.J.; Militello, M.C.

    1993-01-01

    We have deposited diamond-like carbon (DLC) and amorphous SiN films on a tool steel coupon. In order to make the DLC adhere to the metal, we used an interlayer of amorphous SiN, taking advantage of the fact that the SiN coating adheres to the metal and the DLC adheres to the SiN. The DLC/SiN-coated substrate showed a significant reduction in friction compared with either uncoated or SiN-coated substrates in our laboratory bench tester after lubricated sliding for 30 h. In addition, on the basis of surface profilometry analysis, the DLC/SiN-coated plate showed less wear and a much smoother surface. The films were analyzed using X-ray photo-electron spectroscopy and sputter depth profiling. Our results suggest that DLC is a promising coating for wear protection. (orig.)

  10. Raman Microscopic Analysis of Internal Stress in Boron-Doped Diamond

    Directory of Open Access Journals (Sweden)

    Kevin E. Bennet

    2015-05-01

    Full Text Available Analysis of the induced stress on undoped and boron-doped diamond (BDD thin films by confocal Raman microscopy is performed in this study to investigate its correlation with sample chemical composition and the substrate used during fabrication. Knowledge of this nature is very important to the issue of long-term stability of BDD coated neurosurgical electrodes that will be used in fast-scan cyclic voltammetry, as potential occurrence of film delaminations and dislocations during their surgical implantation can have unwanted consequences for the reliability of BDD-based biosensing electrodes. To achieve a more uniform deposition of the films on cylindrically-shaped tungsten rods, substrate rotation was employed in a custom-built chemical vapor deposition reactor. In addition to visibly preferential boron incorporation into the diamond lattice and columnar growth, the results also reveal a direct correlation between regions of pure diamond and enhanced stress. Definite stress release throughout entire film thicknesses was found in the current Raman mapping images for higher amounts of boron addition. There is also a possible contribution to the high values of compressive stress from sp2 type carbon impurities, besides that of the expected lattice mismatch between film and substrate.

  11. Synthesis of diamond-like carbon via PECD using a streaming neutral gas injection hollow cathode

    International Nuclear Information System (INIS)

    Pacho, A.; Pares, E.; Ramos, H.; Mendenilla, A.; Malapit, G.

    2009-01-01

    A streaming neutral gas injection hollow cathode system was used to deposit diamond-like carbon films via plasma enhanced chemical vapor deposition on silicon and nickel-coated silicon substrates with acetylene and hydrogen as reactant gases. Samples were characterized using SEM and Raman spectroscopy. The work presented here aims to demonstrate the capability of the system to synthesize carbonaceous films and is starting point towards work on formation of carbon nanostructures. (author)

  12. Improvement in the degradation resistance of silicon nanostructures by the deposition of diamond-like carbon films

    Energy Technology Data Exchange (ETDEWEB)

    Klyui, N. I., E-mail: klyui@isp.kiev.ua; Semenenko, M. A.; Khatsevich, I. M.; Makarov, A. V.; Kabaldin, A. N. [National Academy of Sciences of Ukraine, Lashkarev Institute of Semiconductor Physics (Ukraine); Fomovskii, F. V. [Kremenchug National University (Ukraine); Han, Wei [Jilin University, College of Physics (China)

    2015-08-15

    It is established that the deposition of a diamond-like film onto a structure with silicon nanoclusters in a silicon dioxide matrix yields an increase in the long-wavelength photoluminescence intensity of silicon nanoclusters due to the passivation of active-recombination centers with hydrogen and a shift of the photoluminescence peak to the region of higher photosensitivity of silicon-based solar cells. It is also shown that, due to the deposited diamond-like film, the resistance of such a structure to degradation upon exposure to γ radiation is improved, which is also defined by the effect of the passivation of radiation-induced activerecombination centers by hydrogen that is released from the films during treatment.

  13. Advances in the electro-spark deposition coating process

    International Nuclear Information System (INIS)

    Johnson, R.N.; Sheldon, G.L.

    1986-04-01

    Electro-spark deposition (ESD) is a pulsed-arc micro-welding process using short-duration, high-current electrical pulses to deposit an electrode material on a metallic substrate. It is one of the few methods available by which a fused, metallurgically bonded coating can be applied with such a low total heat input that the bulk substrate material remains at or near ambient temperatures. The short duration of the electrical pulse allows an extremely rapid solidification of the deposited material and results in an exceptionally fine-grained, homogenous coating that approaches (and with some materials, actually is) an amorphous structure. This structure is believed to contribute to the good tribological and corrosion performance observed for hardsurfacing materials used in the demanding environments of high temperatures, liquid metals, and neutron irradiation. A brief historical review of the process is provided, followed by descriptions of the present state-of-the-art and of the performance and applications of electro-spark deposition coatings in liquid-metal-cooled nuclear reactors

  14. ZrN coatings deposited by high power impulse magnetron sputtering and cathodic arc techniques

    Energy Technology Data Exchange (ETDEWEB)

    Purandare, Yashodhan, E-mail: Y.Purandare@shu.ac.uk; Ehiasarian, Arutiun; Hovsepian, Papken [Nanotechnology Centre for PVD Research, Materials and Engineering Research Institute, Sheffield Hallam University, Sheffield S1 1WB (United Kingdom); Santana, Antonio [Ionbond AG Olten, Industriestrasse 211, CH-4600 Olten (Switzerland)

    2014-05-15

    Zirconium nitride (ZrN) coatings were deposited on 1 μm finish high speed steel and 316L stainless steel test coupons. Cathodic Arc (CA) and High Power Impulse Magnetron Sputtering (HIPIMS) + Unbalanced Magnetron Sputtering (UBM) techniques were utilized to deposit coatings. CA plasmas are known to be rich in metal and gas ions of the depositing species as well as macroparticles (droplets) emitted from the arc sports. Combining HIPIMS technique with UBM in the same deposition process facilitated increased ion bombardment on the depositing species during coating growth maintaining high deposition rate. Prior to coating deposition, substrates were pretreated with Zr{sup +} rich plasma, for both arc deposited and HIPIMS deposited coatings, which led to a very high scratch adhesion value (L{sub C2}) of 100 N. Characterization results revealed the overall thickness of the coatings in the range of 2.5 μm with hardness in the range of 30–40 GPa depending on the deposition technique. Cross-sectional transmission electron microscopy and tribological experiments such as dry sliding wear tests and corrosion studies have been utilized to study the effects of ion bombardment on the structure and properties of these coatings. In all the cases, HIPIMS assisted UBM deposited coating fared equal or better than the arc deposited coatings, the reasons being discussed in this paper. Thus H+U coatings provide a good alternative to arc deposited where smooth, dense coatings are required and macrodroplets cannot be tolerated.

  15. Synthesis of diamond films by pulsed liquid injection chemical vapor deposition using a mixture of acetone and water as precursor

    International Nuclear Information System (INIS)

    Apatiga, L.M.; Morales, J.

    2009-01-01

    A chemical vapor deposition reactor based on the flash evaporation of an organic liquid precursor was used to grow diamond films on Si substrates. An effective pulsed liquid injection mechanism consisting of an injector, normally used for fuel injection in internal combustion engines, injects micro-doses of the precursor to the evaporation zone at 280 o C and is instantly evaporated. The resulting vapor mixture is transported by a carrier gas to the high-temperature reaction chamber where the diamond nucleates and grows on the substrate surface at temperatures ranging from 750 to 850 o C. The injection frequency, opening time, number of pulses and other injector parameters are controlled by a computer-driven system. The diamond film morphology and structure were characterized by scanning electron microscopy and Raman spectroscopy. The as-deposited diamond films show a ball-shaped morphology with a grain size that varies from 100 to 400 nm, as well as the characteristic diamond Raman band at 1332 cm -1 . The effects of the experimental parameters and operation principle on the diamond films quality are analyzed and discussed in terms of crystallinity, composition, structure, and morphology.

  16. Simulations, fabrication and characterization of diamond coated Love wave-type SAW sensors

    Czech Academy of Sciences Publication Activity Database

    Talbi, A.; Soltani, A.; Rumeau, A.; Taylor, Andrew; Drbohlavová, L.; Klimša, Ladislav; Kopeček, Jaromír; Fekete, Ladislav; Krečmarová, Marie; Mortet, Vincent

    2015-01-01

    Roč. 212, č. 11 (2015), 2606-2610 ISSN 1862-6300 R&D Projects: GA MŠk LO1409; GA MŠk(CZ) LM2011029; GA ČR GA13-31783S Institutional support: RVO:68378271 Keywords : acoustic sensors * chemical vapor deposition * diamond * nanocrystalline materials * quartz * surface acoustic waves Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.648, year: 2015

  17. A wear simulation study of nanostructured CVD diamond-on-diamond articulation involving concave/convex mating surfaces

    Science.gov (United States)

    Baker, Paul A.; Thompson, Raymond G.; Catledge, Shane A.

    2015-01-01

    Using microwave-plasma Chemical Vapor Deposition (CVD), a 3-micron thick nanostructured-diamond (NSD) layer was deposited onto polished, convex and concave components that were machined from Ti-6Al-4V alloy. These components had the same radius of curvature, 25.4mm. Wear testing of the surfaces was performed by rotating articulation of the diamond-deposited surfaces (diamond-on-diamond) with a load of 225N for a total of 5 million cycles in bovine serum resulting in polishing of the diamond surface and formation of very shallow, linear wear grooves of less than 50nm depth. The two diamond surfaces remained adhered to the components and polished each other to an average surface roughness that was reduced by as much as a factor of 80 for the most polished region located at the center of the condyle. Imaging of the surfaces showed that the initial wearing-in phase of diamond was only beginning at the end of the 5 million cycles. Atomic force microscopy, scanning electron microscopy, Raman spectroscopy, and surface profilometry were used to characterize the surfaces and verify that the diamond remained intact and uniform over the surface, thereby protecting the underlying metal. These wear simulation results show that diamond deposition on Ti alloy has potential application for joint replacement devices with improved longevity over existing devices made of cobalt chrome and ultra-high molecular weight polyethylene (UHMWPE). PMID:26989457

  18. Characteristics of CrAlSiN + DLC coating deposited by lateral rotating cathode arc PVD and PACVD process

    Energy Technology Data Exchange (ETDEWEB)

    Lukaszkowicz, Krzysztof, E-mail: krzysztof.lukaszkowicz@polsl.pl [Institute of Engineering Materials and Biomaterials, Silesian University of Technology, Konarskiego St. 18A, 44-100 Gliwice (Poland); Sondor, Jozef, E-mail: j.sondor@liss.cz [LISS, a.s., Dopravni 2603, 756 61 Roznov p.R. (Czech Republic); Balin, Katarzyna, E-mail: katarzyna.balin@us.edu.pl [A. Chełkowski Institute of Physic, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland); Kubacki, Jerzy, E-mail: jerzy.kubacki@us.edu.pl [A. Chełkowski Institute of Physic, University of Silesia, Uniwersytecka 4, 40-007 Katowice (Poland)

    2014-09-01

    Highlights: • The chemical composition of the CrAlSiN + DLC coatings was studied. • The coatings have nanostructural character with fine crystallites. • Their average size grain is less than 10 nm. • The coatings demonstrate friction coefficient within the range 0.05–0.07. • The coating demonstrated a dense cross-sectional morphology as well as good adhesion to the substrate. - Abstract: Coating system composed of CrAlSiN film covered by diamond-like carbon (DLC)-based lubricant, deposited on hot work tool steel substrate was the subject of the research. The CrAlSiN and DLC layers were deposited by PVD lateral rotating ARC-cathodes (LARC) and PACVD technology on the X40CrMoV5-1 respectively. HRTEM investigation shows an amorphous character of DLC layer. It was found that the tested CrAlSiN layer has a nanostructural character with fine crystallites while their average size is less than 10 nm. Based on the XRD pattern of the CrAlSiN, the occurrence of fcc phase was only observed in the coating, the texture direction 〈3 1 1〉 is perpendicular to the sample surface. Combined SEM, AES and ToF-SIMS studies confirmed assumed chemical composition and layered structure of the coating. The chemical distribution of the elements inside the layers and at the interfaces was analyzed by SEM and AES methods. It was shown that additional CrN layer is present between substrate and CrAlSiN coating. The atomic concentration of the particular elements of DLC and CrAlSiN layer was calculated from the XPS measurements. In sliding dry friction conditions the friction coefficient for the investigated elements is set in the range between 0.05 and 0.07. The investigated coating reveals high wear resistance. The coating demonstrated a dense cross-sectional morphology as well as good adhesion to the substrate.

  19. Corrosion properties of aluminium coatings deposited on sintered NdFeB by ion-beam-assisted deposition

    Energy Technology Data Exchange (ETDEWEB)

    Mao Shoudong; Yang Hengxiu; Li Jinlong; Huang Feng [Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, 519 Zhuangshi Road, Ningbo 315201 (China); Song Zhenlun, E-mail: songzhenlun@nimte.ac.cn [Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, 519 Zhuangshi Road, Ningbo 315201 (China)

    2011-04-15

    Pure Al coatings were deposited by direct current (DC) magnetron sputtering to protect sintered NdFeB magnets. The effects of Ar{sup +} ion-beam-assisted deposition (IBAD) on the structure and the corrosion behaviour of Al coatings were investigated. The Al coating prepared by DC magnetron sputtering with IBAD (IBAD-Al-coating) had fewer voids than the coating without IBAD (Al-coating). The corrosion behaviour of the Al-coated NdFeB specimens was investigated by potentiodynamic polarisation, a neutral salt spray (NSS) test, and electrochemical impedance spectroscopy (EIS). The pitting corrosion of the Al coatings always began at the voids of the grain boundaries. Bombardment by the Ar{sup +} ion-beams effectively improved the corrosion resistance of the IBAD-Al-coating.

  20. Nanostructured thin film coatings with different strengthening effects

    Directory of Open Access Journals (Sweden)

    Panfilov Yury

    2017-01-01

    Full Text Available A number of articles on strengthening thin film coatings were analyzed and a lot of unusual strengthening effects, such as super high hardness and plasticity simultaneously, ultra low friction coefficient, high wear-resistance, curve rigidity increasing of drills with small diameter, associated with process formation of nanostructured coatings by the different thin film deposition methods were detected. Vacuum coater with RF magnetron sputtering system and ion-beam source and arc evaporator for nanostructured thin film coating manufacture are represented. Diamond Like Carbon and MoS2 thin film coatings, Ti, Al, Nb, Cr, nitride, carbide, and carbo-nitride thin film materials are described as strengthening coatings.

  1. Ion beam induced surface graphitization of CVD diamond for x-ray beam position monitor applications

    International Nuclear Information System (INIS)

    Liu, Chian; Shu, D.; Kuzay, T.M.; Wen, L.; Melendres, C.A.; Argonne National Lab., IL

    1996-01-01

    The Advanced Photon Source at ANL is a third-generation synchrotron facility that generates powerful x-ray beams on its undulator beamlines. It is important to know the position and angle of the x- ray beam during experiments. Due to very high heat flux levels, several patented x-ray beam position monitors (XBPM) exploiting chemical vapor deposition (CVD) diamond have been developed. These XBPMs have a thin layer of low-atomic-mass metallic coating so that photoemission from the x rays generate a minute but measurable current for position determination. Graphitization of the CVD diamond surface creates a very thin, intrinsic and conducting layer that can stand much higher temperatures and minimal x-ray transmission losses compared to the coated metallic layers. In this paper, a laboratory sputter ion source was used to transform selected surfaces of a CVD diamond substrate into graphite. The effect of 1-5 keV argon ion bombardment on CVD diamond surfaces at various target temperatures from 200 to 500 C was studied using Auger electron spectroscopy and in-situ electrical resistivity measurements. Graphitization after the ion bombardment has been confirmed and optimum conditions for graphitization studied. Raman spectroscopy was used to identify the overall diamond structure in the bulk of CVD diamond substrate after the ion bombardments. It was found that target temperature plays an important role in stability and electrical conductivity of the irradiated CVD diamonds

  2. Effects of deposition temperature on electrodeposition of zinc–nickel alloy coatings

    International Nuclear Information System (INIS)

    Qiao, Xiaoping; Li, Helin; Zhao, Wenzhen; Li, Dejun

    2013-01-01

    Highlights: ► Both normal and anomalous deposition can be realized by changing bath temperature. ► The Ni content in Zn–Ni alloy deposit increases sharply as temperature reach 60 °C. ► The abrupt change in coating composition is caused by the shift of cathodic potential. ► The deposition temperature has great effect on microstructure of Zn–Ni alloy deposit. -- Abstract: Zinc–nickel alloy coatings were electrodeposited on carbon steel substrates from the ammonium chloride bath at different temperatures. The composition, phase structure and morphology of these coatings were analyzed by energy dispersive spectrometer, X-ray diffractometer and scanning electron microscopy respectively. Chronopotentiometry and potentiostatic methods were also employed to analyze the possible causes of the composition and structure changes induced by deposition temperature. It has been shown that both normal and anomalous co-deposition of zinc and nickel could be realized by changing deposition temperature under galvanostatic conditions. The abrupt changes in the composition and phase structure of the zinc–nickel alloy coatings were observed when deposition temperature reached 60 °C. The sharply decrease of current efficiency for zinc–nickel co-deposition was also observed when deposition temperature is higher than 40 °C. Analysis of the partial current densities showed that the decrease of current efficiency with the rise of deposition temperature was due to the enhancement of the hydrogen evolution. It was also confirmed that the ennoblement of cathodic potential was the cause for the increase of nickel content in zinc–nickel alloy coatings as a result of deposition temperature rise. The good zinc–nickel alloy coatings with compact morphology and single γ phase could be obtained when the deposition temperature was fixed at 30–40 °C

  3. Effect of Coating Thickness on the Properties of TiN Coatings Deposited on Tool Steels Using Cathodic Arc Pvd Technique

    Science.gov (United States)

    Mubarak, A.; Akhter, Parvez; Hamzah, Esah; Mohd Toff, Mohd Radzi Hj.; Qazi, Ishtiaq A.

    Titanium nitride (TiN) widely used as hard coating material, was coated on tool steels, namely on high-speed steel (HSS) and D2 tool steel by physical vapor deposition method. The study concentrated on cathodic arc physical vapor deposition (CAPVD), a technique used for the deposition of hard coatings for tooling applications, and which has many advantages. The main drawback of this technique, however, is the formation of macrodroplets (MDs) during deposition, resulting in films with rougher morphology. Various standard characterization techniques and equipment, such as electron microscopy, atomic force microscopy, hardness testing machine, scratch tester, and pin-on-disc machine, were used to analyze and quantify the following properties and parameters: surface morphology, thickness, hardness, adhesion, and coefficient of friction (COF) of the deposited coatings. Surface morphology revealed that the MDs produced during the etching stage, protruded through the TiN film, resulting in film with deteriorated surface features. Both coating thickness and indentation loads influenced the hardness of the deposited coatings. The coatings deposited on HSS exhibit better adhesion compared to those on D2 tool steel. Standard deviation indicates that the coating deposited with thickness around 6.7 μm showed the most stable trend of COF versus sliding distance.

  4. Electrolytic deposition and corrosion resistance of Zn–Ni coatings

    Indian Academy of Sciences (India)

    Zn–Ni coatings were deposited under galvanostatic conditions on steel substrate (OH18N9). The influence of current density of deposition on the surface morphology, chemical and phase composition was investigated. The corrosion resistance of Zn–Ni coatings obtained at current density 10–25 mA cm-2 are measured, ...

  5. Laser diagnostics of a diamond depositing chemical vapour deposition gas-phase environment

    International Nuclear Information System (INIS)

    Smith, James Anthony

    2002-01-01

    Studies have been carried out to understand the gas-phase chemistry underpinning diamond deposition in hot filament and DC-arcjet chemical vapour deposition (CVD) systems. Resonance enhanced Multiphoton lonisation (REMPI) techniques were used to measure the relative H atom and CH 3 radical number densities and local gas temperatures prevalent in a hot filament reactor, operating on Ch 4 /H 2 and C 2 H 2 /H 2 gas mixtures. These results were compared to a 3D-computer simulation, and hence provided an insight into the nature of the gas-phase chemistry with particular reference to C 2 →C 1 species conversion. Similar experimental and theoretical studies were also carried out to explain the chemistry involved in NH 3 /CH 4 /H 2 and N 2 /CH 4 /H 2 gas mixtures. It was demonstrated that the reactive nature of the filament surface was dependent on the addition of NH 3 , influencing atomic hydrogen production, and thus the H/C/N gas-phase chemistry. Studies of the DC-arcjet diamond CVD reactor consisted of optical emission spectroscopic studies of the plume during deposition from an Ar/H 2 /CH 4 /N 2 gas mixture. Spatially resolved species emission intensity maps were obtained for C 2 (d→a), CN(B→X) and H β from Abel-inverted datasets. The C 2 (d→a) and CN(B→X) emission intensity maps both show local maxima near the substrate surface. SEM and Laser Raman analyses indicate that N 2 additions lead to a reduction in film quality and growth rate. Photoluminescence and SIMS analyses of the grown films provide conclusive evidence of nitrogen incorporation (as chemically bonded CN). Absolute column densities of C 2 (a) in a DC-arcjet reactor operating on an Ar/H 2 /CH 4 gas mixture, were measured using Cavity ring down spectroscopy. Simulations of the measured C 2 (v=0) transition revealed a rotational temperature of ∼3300 K. This gas temperature is similar to that deduced from optical emission spectroscopy studies of the C 2 (d→a) transition. (author)

  6. Diamond nanophotonics

    Directory of Open Access Journals (Sweden)

    Katja Beha

    2012-12-01

    Full Text Available We demonstrate the coupling of single color centers in diamond to plasmonic and dielectric photonic structures to realize novel nanophotonic devices. Nanometer spatial control in the creation of single color centers in diamond is achieved by implantation of nitrogen atoms through high-aspect-ratio channels in a mica mask. Enhanced broadband single-photon emission is demonstrated by coupling nitrogen–vacancy centers to plasmonic resonators, such as metallic nanoantennas. Improved photon-collection efficiency and directed emission is demonstrated by solid immersion lenses and micropillar cavities. Thereafter, the coupling of diamond nanocrystals to the guided modes of micropillar resonators is discussed along with experimental results. Finally, we present a gas-phase-doping approach to incorporate color centers based on nickel and tungsten, in situ into diamond using microwave-plasma-enhanced chemical vapor deposition. The fabrication of silicon–vacancy centers in nanodiamonds by microwave-plasma-enhanced chemical vapor deposition is discussed in addition.

  7. Deposition and Characterization of TRISO Coating Layers

    International Nuclear Information System (INIS)

    Kim, Do Kyung; Kim, Min Woo; Lee, Hyeon Keun; Choi, Doo Jin; Kim, Jun Kyu; Cho, Sung Hyuk

    2008-03-01

    Both ZrC and SiC layers are crucial layers in TRISO coated fuel particles since they prevent diffusion of fission products and provide mechanical strength for the fuel particle. However, each layer has its own defects, so the purpose of this study is to complement such defects of these layers. In this study, we carried out thermodynamic simulations before actual experiments. With these simulation results, we deposited the ZrC layers on SiC/graphite substrates through CVD process. SiC films on graphite have different microstructures which are a hemispherical angular, domed top and faceted structure at different deposition temperature, respectively. According to the microstructures of SiC, preferred orientation, hardness and elastic modules of deposited ZrC layer were changed. TRISO particles. The fracture the SiC coating layer occurred by the tensile stress due to the traditional pressure vessel failure criteria. It is important to find fracture stress of SiC coating layer by the internal pressurization test method. The finite-element analysis was carried out to obtain the empirical equation of strength evaluation. By using this empirical equation, the mechanical properties of several types of SiC coating film with different microstructure and thicknesses will discussed

  8. Deposition and Characterization of TRISO Coating Layers

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Do Kyung; Kim, Min Woo; Lee, Hyeon Keun [KAIST, Daejeon (Korea, Republic of); Choi, Doo Jin; Kim, Jun Kyu; Cho, Sung Hyuk [Younsei University, Seoul (Korea, Republic of)

    2008-03-15

    Both ZrC and SiC layers are crucial layers in TRISO coated fuel particles since they prevent diffusion of fission products and provide mechanical strength for the fuel particle. However, each layer has its own defects, so the purpose of this study is to complement such defects of these layers. In this study, we carried out thermodynamic simulations before actual experiments. With these simulation results, we deposited the ZrC layers on SiC/graphite substrates through CVD process. SiC films on graphite have different microstructures which are a hemispherical angular, domed top and faceted structure at different deposition temperature, respectively. According to the microstructures of SiC, preferred orientation, hardness and elastic modules of deposited ZrC layer were changed. TRISO particles. The fracture the SiC coating layer occurred by the tensile stress due to the traditional pressure vessel failure criteria. It is important to find fracture stress of SiC coating layer by the internal pressurization test method. The finite-element analysis was carried out to obtain the empirical equation of strength evaluation. By using this empirical equation, the mechanical properties of several types of SiC coating film with different microstructure and thicknesses will discussed.

  9. XPS, XRD and laser Raman analysis of surface modified of 6150 steel substrates for the deposition of thick and adherent diamond-like carbon coatings

    Energy Technology Data Exchange (ETDEWEB)

    Silva, William de Melo; Carneiro, Jose Rubens Goncalves, E-mail: williammelosilva@gmail.com [Pontificia Universidade Catolica de Minas Gerais (PUC-MG), Belo Horizonte (Brazil). Dept. de Engenharia Mecanica; Trava-Airoldi, Vladimir Jesus [Associate Laboratory of Sensors and Materials, National Institute for Space Research, Sao Jose dos Campos, SP (Brazil)

    2013-11-01

    Although the 6150 steel has an excellent fatigue and impact resistance, it is unsuitable to operate it when the corrosion is a limited factor. We propose here a sequence of steel pre-treatment by carburizing, carbonitriding and nitriding in order to improve the poor adhesion between Diamond Like-Carbon coatings on steel. This sequence is our attempt to reduce the difference between the coefficients of thermal expansion of steel and DLC through the graded interface. This work demonstrates the quantitative analysis of the molecules present at surface using X-ray photoelectron spectroscopy. The crystallographic structures are investigated by X-ray diffraction which shows the formation of carbides and nitride phases. Raman spectroscopy reveals the carburizing surface characteristics where DLC coating is nucleated and grown at the substrate. At the end of the analysis it is possible to verify which molecules and phases are formed on the steel surface interface after each step of pre-treatment. (author)

  10. XPS, XRD and laser Raman analysis of surface modified of 6150 steel substrates for the deposition of thick and adherent diamond-like carbon coatings

    International Nuclear Information System (INIS)

    Silva, William de Melo; Carneiro, Jose Rubens Goncalves

    2013-01-01

    Although the 6150 steel has an excellent fatigue and impact resistance, it is unsuitable to operate it when the corrosion is a limited factor. We propose here a sequence of steel pre-treatment by carburizing, carbonitriding and nitriding in order to improve the poor adhesion between Diamond Like-Carbon coatings on steel. This sequence is our attempt to reduce the difference between the coefficients of thermal expansion of steel and DLC through the graded interface. This work demonstrates the quantitative analysis of the molecules present at surface using X-ray photoelectron spectroscopy. The crystallographic structures are investigated by X-ray diffraction which shows the formation of carbides and nitride phases. Raman spectroscopy reveals the carburizing surface characteristics where DLC coating is nucleated and grown at the substrate. At the end of the analysis it is possible to verify which molecules and phases are formed on the steel surface interface after each step of pre-treatment. (author)

  11. XPS, XRD and laser raman analysis of surface modified of 6150 steel substrates for the deposition of thick and adherent diamond-like carbon coatings

    Directory of Open Access Journals (Sweden)

    William de Melo Silva

    2013-06-01

    Full Text Available Although the 6150 steel has an excellent fatigue and impact resistance, it is unsuitable to operate it when the corrosion is a limited factor. We propose here a sequence of steel pre-treatment by carburizing, carbonitriding and nitriding in order to improve the poor adhesion between Diamond Like-Carbon coatings on steel. This sequence is our attempt to reduce the difference between the coefficients of thermal expansion of steel and DLC through the graded interface. This work demonstrates the quantitative analysis of the molecules present at surface using X-ray photoelectron spectroscopy. The crystallographic structures are investigated by X-ray diffraction which shows the formation of carbides and nitride phases. Raman spectroscopy reveals the carburizing surface characteristics where DLC coating is nucleated and grown at the substrate. At the end of the analysis it is possible to verify which molecules and phases are formed on the steel surface interface after each step of pre-treatment.

  12. Ion Deposited Carbon Coatings.

    Science.gov (United States)

    1983-07-01

    PAGE ("’hen Dita t,,I,, efl TABLE OF CONTENTS Section No. Title Page No. 1.0 OBJECTIVE 1 2.0 SCOPE 2 3.0 BACKGROUND 3 4.0 COATINGS DEPOSITION 4 4.1...scientific, ards of measure. The Committee, and Confer- technical, practical, and teaching purposes.ence voting members, are leading professional On the

  13. Progress Toward Meeting NIF Specifications for Vapor Deposited Polyimide Ablator Coatings

    International Nuclear Information System (INIS)

    Letts, Stephan A.; Anthamatten, Mitchell; Buckley, Steven R.; Fearon, Evelyn; Nissen, April E.H.; Cook, Robert C.

    2004-01-01

    We are developing an evaporative coating technique for deposition of thick polyimide (PI) ablator layers on ICF targets. The PI coating technique utilizes stoichiometrically controlled fluxes from two Knudsen cell evaporators containing a dianhydride and a diamine to deposit a polyamic acid (PAA) coating. Heating the PAA coating to 300 deg. C converts the PAA coating to a polyimide. Coated shells are rough due to particles on the substrate mandrels and from damage to the coating caused by the agitation used to achieve a uniform coating. We have developed a smoothing process that exposes an initially rough PAA coated shell to solvent vapor using gas levitation. We found that after smoothing the coatings developed a number of wide (low-mode) defects. We have identified two major contributors to low-mode roughness: surface hydrolysis, and deformation during drying/curing. By minimizing air exposure prior to vapor smoothing, avoiding excess solvent sorption during vapor smoothing, and using slow drying we are able to deposit and vapor smooth coatings 160 μm thick with a surface roughness less than 20 nm RMS

  14. Diamond like carbon coatings deposited by microwave plasma CVD ...

    Indian Academy of Sciences (India)

    WINTEC

    photoelectron spectroscopy (XPS) and spectroscopic ellipsometry techniques for estimating sp. 3. /sp. 2 ratio. ... ion beam deposition (Savvidas 1986), pulsed laser deposi- ... carrier gas (10 sccm) by passing 150 watts of microwave power.

  15. Dosimetric characterization of chemical-vapor-deposited diamond film irradiated with UV and beta radiation

    Science.gov (United States)

    Meléndrez, R.; Chernov, V.; Pedroza-Montero, M.; Barboza-Flores, M.

    2003-03-01

    Diamond is an excellent prospect for clinical radiation dosimetry due to its tissue-equivalence properties and being chemically inert. The use of diamond in radiation dosimetry has been halted by the high market price; although recently the capability of growing high quality polycrystalline has renewed the interest in using diamond films as detectors and dosimeters. In the present work we have characterized the dosimetric properties of diamond films synthesized by using chemical vapor deposition. The thermoluminescence (TL) of UV and beta exposed samples shows a glow curve composed of at least four peaks; one located around 587 K presents excellent TL properties suitable for dosimetric applications with ionizing and non ionizing radiation. The TL excitation spectrum exhibits maximum TL efficiency at 220 nm. The samples show regions of linear as well as supralinear behavior as a function or irradiation dose. The linear dose dependence was found for up to sixteen minutes of UV irradiation and 300 Gy for beta irradiated samples. The activation energy and the frequency factor were determined and found in the range of 0.32 - 0.89 eV and 1.1x10^2 - 2x10^8s_-1, respectively. The observed TL performance is reasonable appropriate to justify further investigation of diamond films as radiation dosimeters.

  16. Recent Advances in Diamond Detectors

    CERN Document Server

    Trischuk, W.

    2008-01-01

    With the commissioning of the LHC expected in 2009, and the LHC upgrades expected in 2012, ATLAS and CMS are planning for detector upgrades for their innermost layers requiring radiation hard technologies. Chemical Vapor Deposition (CVD) diamond has been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle and CDF and is now planned for all LHC experiments. This material is now being considered as an alternate sensor for use very close to the interaction region of the super LHC where the most extreme radiation conditions will exist. Recently the RD42 collaboration constructed, irradiated and tested polycrystalline and single-crystal chemical vapor deposition diamond sensors to the highest fluences available. We present beam test results of chemical vapor deposition diamond up to fluences of 1.8 x 10^16 protons/cm^2 showing that both polycrystalline and single-crystal chemical vapor deposition diamonds follow a single damage curve allowing one t...

  17. Friction and wear study of diamond-like carbon gradient coatings on Ti6Al4V substrate prepared by plasma source ion implant-ion beam enhanced deposition

    International Nuclear Information System (INIS)

    Jiang, Shuwen; Jiang Bin; Li Yan; Li Yanrong; Yin Guangfu; Zheng Changqiong

    2004-01-01

    DLC gradient coatings had been deposited on Ti6Al4V alloy substrate by plasma source ion implantation-ion beam enhanced deposition method and their friction and wear behavior sliding against ultra high molecular weight polyethylene counterpart were investigated. The results showed that DLC gradient coated Ti6Al4V had low friction coefficient, which reduced 24, 14 and 10% compared with non-coated Ti6Al4V alloy under dry sliding, lubrication of bovine serum and 0.9% NaCl solution, respectively. DLC gradient coated Ti6Al4V showed significantly improved wear resistance, the wear rate was about half of non-coated Ti6Al4V alloy. The wear of ultra high molecular weight polyethylene counterpart was also reduced. High adhesion to Ti6Al4V substrate of DLC gradient coatings and surface structure played important roles in improved tribological performance, serious oxidative wear was eliminated when DLC gradient coating was applied to the Ti6Al4V alloy

  18. Silver doped hydroxyapatite coatings by sacrificial anode deposition under magnetic field.

    Science.gov (United States)

    Swain, S; Rautray, T R

    2017-09-13

    Uniform distribution of silver (Ag) in the hydroxyapatite (HA) coated Ti surface has been a concern for which an attempt has been made to dope Ag in HA coating with and without magnetic field. Cathodic deposition technique was employed to coat Ag incorporated hydroxyapatite coating using a sacrificial silver anode method by using NdFeB bar magnets producing 12 Tesla magnetic field. While uniform deposition of Ag was observed in the coatings under magnetic field, dense coating was evident in the coating without magnetic field conditions. Uniformly distributed Ag incorporated HA in the present study has potential to fight microorganism while providing osseoconduction properties of the composite coating.

  19. Diamond-like carbon films deposited by a hybrid ECRCVD system

    International Nuclear Information System (INIS)

    Guo, C.T.; Dittrich, K.-H.

    2007-01-01

    A novel hybrid technique for diamond-like carbon (DLC) film deposition has been developed. This technique combines the electron cyclotron resonance chemical vapor deposition (ECRCVD) of C 2 H 2 and metallic magnetron sputtering. Here we described how DLC film is used for a variety of applications such as stamper, PCB micro-tools, and threading form-tools by taking advantage of hybrid ECRCVD system. The structure of the DLC films is delineated by a function of bias voltages by Raman spectroscopy. This function includes parameters such as dependence of G peak positions and the intensity ratio (I D /I G ). Atomic force microscope (AFM) examines the root-mean-square (R.M.S.) roughness and the surface morphology. Excellent adhesion and lower friction coefficients of a DLC film were also assessed

  20. Toroidal plasma enhanced CVD of diamond films

    International Nuclear Information System (INIS)

    Zvanya, John; Cullen, Christopher; Morris, Thomas; Krchnavek, Robert R.; Holber, William; Basnett, Andrew; Basnett, Robert; Hettinger, Jeffrey

    2014-01-01

    An inductively coupled toroidal plasma source is used as an alternative to microwave plasmas for chemical vapor deposition of diamond films. The source, operating at a frequency of 400 kHz, synthesizes diamond films from a mixture of argon, methane, and hydrogen. The toroidal design has been adapted to create a highly efficient environment for diamond film deposition: high gas temperature and a short distance from the sample to the plasma core. Using a toroidal plasma geometry operating in the medium frequency band allows for efficient (≈90%) coupling of AC line power to the plasma and a scalable path to high-power and large-area operation. In test runs, the source generates a high flux of atomic hydrogen over a large area, which is favorable for diamond film growth. Using a deposition temperature of 900–1050 °C and a source to sample distance of 0.1–2.0 cm, diamond films are deposited onto silicon substrates. The results showed that the deposition rate of the diamond films could be controlled using the sample temperature and source to sample spacing. The results also show the films exhibit good-quality polycrystalline diamond as verified by Raman spectroscopy, x-ray diffraction, and scanning electron microscopy. The scanning electron microscopy and x-ray diffraction results show that the samples exhibit diamond (111) and diamond (022) crystallites. The Raman results show that the sp 3 peak has a narrow spectral width (FWHM 12 ± 0.5 cm −1 ) and that negligible amounts of the sp 2 band are present, indicating good-quality diamond films

  1. DEPOSITION AND PROPERTY CHARACTERISATION OF TaN COATINGS DEPOSITED WITH DIFFERENT NITROGEN CONTENTS

    Directory of Open Access Journals (Sweden)

    Gilberto Bejarano Gaitán

    Full Text Available This study focused on the study of the influence of nitrogen content on the microstructure, chemical composition, mechanical and tribological properties of TaN coatings deposited on 420 stainless steel and silicon samples (100 using the magnetron sputtering technique. For the deposition of the TaN coatings an argon/nitrogen atmosphere was used, varying the nitrogen flux between 12% and 25%. For the coating characterization, scanning electron microscopy, energydispersive X-ray spectroscopy, atomic force microscopy, X-ray diffraction (XRD, micro-Raman spectroscopy, a microhardness tester, and a ball on disc tribometer were used. A refining of the columnar structure of the coatings, accompanied by a decrease in their thickness with the increased nitrogen content was observed. Initially, fcc-TaN (111 cubic phase growth was observed; this phase was changed to the fcc-TaN (200 above N2 12%. For contents greater than N2 18%, another nitrogen-rich phase was formed and the system tended towards amorphicity, particularly for a coating with N2 25% content. The TaN-1sample deposited with N2 12% in the gas mixture presented the highest micro-hardness value with 21.3GPa and the lowest friction coefficient and wear rate with 0.02 and 1.82x10-7 (mm³/Nm, respectively. From the obtained results, an important relationship between the microstructural, mechanical and tribological properties of the coated samples and their nitrogen content was observed.

  2. Drilling of optical glass with electroplated diamond tools

    Science.gov (United States)

    Wang, A. J.; Luan, C. G.; Yu, A. B.

    2010-10-01

    K9 optical glass drilling experiments were carried out. Bright nickel electroplated diamond tools with small slots and under heat treatment in different temperature were fabricated. Scan electro microscope was applied to analyze the wear of electroplated diamond tool. The material removal rate and grinding ratio were calculated. Machining quality was observed. Bond coating hardness was measured. The experimental results show that coolant is needed for the drilling processes of optical glasses. Heat treatment temperature of diamond tool has influence on wearability of diamond tool and grinding ratio. There were two wear types of electroplated diamond tool, diamond grit wear and bond wear. With the machining processes, wear of diamond grits included fracture, blunt and pull-out, and electroplated bond was gradually worn out. High material removal rates could be obtained by using diamond tool with suitable slot numbers. Bright nickel coating bond presents smallest grains and has better mechanical properties. Bright nickel electroplated diamond tool with slot structure and heat treatment under 200°C was suitable for optical glass drilling.

  3. Plasma Spray-Physical Vapor Deposition (PS-PVD) of Ceramics for Protective Coatings

    Science.gov (United States)

    Harder, Bryan J.; Zhu, Dongming

    2011-01-01

    In order to generate advanced multilayer thermal and environmental protection systems, a new deposition process is needed to bridge the gap between conventional plasma spray, which produces relatively thick coatings on the order of 125-250 microns, and conventional vapor phase processes such as electron beam physical vapor deposition (EB-PVD) which are limited by relatively slow deposition rates, high investment costs, and coating material vapor pressure requirements. The use of Plasma Spray - Physical Vapor Deposition (PS-PVD) processing fills this gap and allows thin (deposited and multilayer coatings of less than 100 microns to be generated with the flexibility to tailor microstructures by changing processing conditions. Coatings of yttria-stabilized zirconia (YSZ) were applied to NiCrAlY bond coated superalloy substrates using the PS-PVD coater at NASA Glenn Research Center. A design-of-experiments was used to examine the effects of process variables (Ar/He plasma gas ratio, the total plasma gas flow, and the torch current) on chamber pressure and torch power. Coating thickness, phase and microstructure were evaluated for each set of deposition conditions. Low chamber pressures and high power were shown to increase coating thickness and create columnar-like structures. Likewise, high chamber pressures and low power had lower growth rates, but resulted in flatter, more homogeneous layers

  4. Electrochemical deposition of coatings of highly entropic alloys from non-aqueous solutions

    Directory of Open Access Journals (Sweden)

    Jeníček V.

    2016-03-01

    Full Text Available The paper deals with electrochemical deposition of coatings of highly entropic alloys. These relatively new materials have been recently intensively studied. The paper describes the first results of electrochemical coating with highly entropic alloys by deposition from non-aqueous solutions. An electrochemical device was designed and coatings were deposited. The coatings were characterised with electronic microscopy scanning, atomic absorption spectrometry and X-ray diffraction methods and the combination of methods of thermic analysis of differential scanning calorimetry and thermogravimetry.

  5. Noble gas studies in vapor-growth diamonds: Comparison with shock-produced diamonds and the origin of diamonds in ureilites

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Junichi; Fukunaga, Kazuya; Ito, Keisuke (Kobe Univ. (Japan))

    1991-07-01

    The authors synthesized vapor-trowth diamonds by two kinds of Chemical Vapor Deposition (CVD) using microwave (MWCVD) and hot filament (HFCVD) ionization of gases, and examined elemental abundances and isotopic compositions of the noble gases trapped in the diamonds. It is remarkable that strong differences existed in the noble gas concentrations in the two kinds of CVD diamonds: large amounts of noble gases were trapped in the MWCVD diamonds, but not in the HFCVD diamonds. The heavy noble gases (Ar to Xe) in the MWCVD diamonds were highly fractionated compared with those in the ambient atmosphere, and are in good agreement with the calculated fractionation patterns for plasma at an electron temperature of 7,000-9,000 K. These results strongly suggest that the trapping mechanism of noble gases in CVD diamonds is ion implantation during diamond growth. The degrees of fractionation of heavy noble gases were also in good agreement with those in ureilites. The vapor-growth hypothesis is discussed in comparison with the impact-shock hypothesis as a better model for the origin of diamonds in ureilites. The diamond (and graphite, amorphous carbon, too) may have been deposited on early condensates such as Re, Ir, W, etc. This model explains the chemical features of vein material in ureilites; the refractory siderophile elements are enriched in carbon and noble gases and low in normal siderophiles. The vapor-growth model is also compatible with the oxygen isotopic data of ureilites which suggests that nebular processes are primarily responsible for the composition of ureilites.

  6. Deposition of titanium coating on SiC fiber by chemical vapor deposition with Ti-I{sub 2} system

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Xian, E-mail: luo_shenfan@hotmail.com; Wu, Shuai; Yang, Yan-qing; Jin, Na; Liu, Shuai; Huang, Bin

    2017-06-01

    Highlights: • The transformation paths of (Ti + I{sub 2}) powder to Ti coating is: Ti + I{sub 2} → (TiI{sub 2}, TiI{sub 3}) → Ti. • Uniform coating was obtained on SiC fiber, but it contained Si and C elements. • Deposition rate of the coating increased with the increase of temperature. • Deposition thickness increased with time and achieved the maximum at 90 min. - Abstract: Titanium coating was prepared on SiC fiber using titanium-iodine (Ti-I{sub 2}) mixture by hot-wall chemical vapor deposition. Thermodynamic analysis and experimental observation were carried out in this work. The thermodynamic analysis of the reactions in the Ti-I{sub 2} system indicates that Ti and I{sub 2} raw powder materials transform to titanium coating as follows: Ti + I{sub 2} → (TiI{sub 2}, TiI{sub 3}), and (TiI{sub 2}, TiI{sub 3}) → Ti. In theory, the conversions of TiI{sub 3} and TiI{sub 2} reach the maximum when Ti:I{sub 2} is 1:1.5, while in actual experiment that reached the maximum when Ti:I{sub 2} was 1:2, as there existed the waste of I{sub 2} due to sublimation. Typical deposited coating is relatively flat and uniform. However, as SiC is prone to react with Ti at high temperatures, the obtained coating contained some Si and C elements except for Ti. So the coating was not a pure Ti coating but contained some carbides and silicides. Deposition rate of the coating increased with the increase of temperature. The deposited thickness increased with the increase of heat preservation time, and achieved the maximum thickness at 90 min.

  7. WC-Co coatings deposited by the electro-thermal chemical spray method

    Energy Technology Data Exchange (ETDEWEB)

    Zhitomirsky, V.N. [Tel Aviv Univ. (Israel). Faculty of Engineering; Wald, S.; Rabani, L.; Zoler, D. [Propulsion Physics Division, SOREQ NRC, 81800, Yavne (Israel); Factor, M.; Roman, I. [School of Applied Sciences, The Hebrew University, 91904, Jerusalem (Israel); Cuperman, S.; Bruma, C. [School of Physics and Astronomy, Tel-Aviv University, 69978, Tel-Aviv (Israel)

    2000-10-02

    A novel thermal spray technology - an electro-thermal chemical spray (ETCS) for producing hard coatings is presented. The experimental coating apparatus consists of a machine gun barrel, a cartridge containing the coating material in powder form, a solid propellant, and a plasma ignition system. The plasma ignition system produces plasma in pulsed mode to ignite the solid propellant. On ignition, the drag force exerted by the combustion gases accelerates the powder particles towards the substrate. Using the ETCS technique, the process of single-shot WC-Co coating deposition on stainless steel substrate was studied. The influence of process parameters (plasma energy, mass of the solid propellant and the coated powder, distance between the gun muzzle and the substrate) on the coating structure and some of its properties were investigated. It was shown that ECTS technique effectively deposited the WC-Co coating with deposition thicknesses of 100-200 {mu}m per shot, while deposition yield of {proportional_to}70% was attained. The WC-Co coatings consisted of carbide particles distributed in amorphous matrix. The powder particle velocity was found to depend on the solid propellant mass and was weakly dependent on the plasma energy, while the particle processing temperature was strongly dependent on the plasma energy and almost independent of the solid propellant mass. Whilst increasing the solid propellant mass from 5 to 7 g, the deposition rate and yield correspondingly increased. When increasing the plasma energy, the temperature of the powder particles increased, the average carbide particle size decreased and their shape became more rounded. The deposition yield and microhardness at first increased and then achieved saturation by increasing the plasma energy. (orig.)

  8. Computer Simulation of Temperature Parameter for Diamond Formation by Using Hot-Filament Chemical Vapor Deposition

    Directory of Open Access Journals (Sweden)

    Chang Weon Song

    2017-12-01

    Full Text Available To optimize the deposition parameters of diamond films, the temperature, pressure, and distance between the filament and the susceptor need to be considered. However, it is difficult to precisely measure and predict the filament and susceptor temperature in relation to the applied power in a hot filament chemical vapor deposition (HF-CVD system. In this study, the temperature distribution inside the system was numerically calculated for the applied powers of 12, 14, 16, and 18 kW. The applied power needed to achieve the appropriate temperature at a constant pressure and other conditions was deduced, and applied to actual experimental depositions. The numerical simulation was conducted using the commercial computational fluent dynamics software ANSYS-FLUENT. To account for radiative heat-transfer in the HF-CVD reactor, the discrete ordinate (DO model was used. The temperatures of the filament surface and the susceptor at different power levels were predicted to be 2512–2802 K and 1076–1198 K, respectively. Based on the numerical calculations, experiments were performed. The simulated temperatures for the filament surface were in good agreement with the experimental temperatures measured using a two-color pyrometer. The results showed that the highest deposition rate and the lowest deposition of non-diamond was obtained at a power of 16 kW.

  9. Nanocrystalline diamond films for biomedical applications

    DEFF Research Database (Denmark)

    Pennisi, Cristian Pablo; Alcaide, Maria

    2014-01-01

    Nanocrystalline diamond films, which comprise the so called nanocrystalline diamond (NCD) and ultrananocrystalline diamond (UNCD), represent a class of biomaterials possessing outstanding mechanical, tribological, and electrical properties, which include high surface smoothness, high corrosion...... performance of nanocrystalline diamond films is reviewed from an application-specific perspective, covering topics such as enhancement of cellular adhesion, anti-fouling coatings, non-thrombogenic surfaces, micropatterning of cells and proteins, and immobilization of biomolecules for bioassays. In order...

  10. Nano-structured yttria-stabilized zirconia coating by electrophoretic deposition

    Energy Technology Data Exchange (ETDEWEB)

    Maleki-Ghaleh, H., E-mail: H_Maleki@sut.ac.ir [Faculty of Materials Engineering, Sahand University of Technology, Tabriz (Iran, Islamic Republic of); Rekabeslami, M. [Faculty of Mechanical Engineering, Materials Science and Engineering Division, K. N. Toosi University of Technology, Tehran (Iran, Islamic Republic of); Shakeri, M.S. [Materials and Energy Research Center, Karaj (Iran, Islamic Republic of); Siadati, M.H. [Faculty of Mechanical Engineering, Materials Science and Engineering Division, K. N. Toosi University of Technology, Tehran (Iran, Islamic Republic of); Javidi, M. [Department of Materials Science and Engineering, School of Engineering, Shiraz University, Shiraz (Iran, Islamic Republic of); Talebian, S.H. [Faculty of Petroleum Engineering, Universiti Technologi Petronas, Perak (Malaysia); Aghajani, H. [Department of Materials Engineering, University of Tabriz, Tabriz (Iran, Islamic Republic of)

    2013-09-01

    The most important role of thermal barrier coatings is to reduce the temperature of the substrate in high temperature applications. Nanoparticle zirconia might be a suitable choice for improving the efficiency of thermal barrier coatings. Nanostructured coatings have lower thermal conduction, higher thermal expansion and lower dimensional variations at higher temperatures in comparison with the microstructured coatings. Electrophoretic deposition has been preferred for thermal barrier coatings due to its simplicity, controllability and low cost. In the present study, three different suspensions of ZrO{sub 2}–8 wt%Y{sub 2}O{sub 3} (40 nm) made with ethanol, acetone and acetyl acetone were used. Electrophoretic deposition was conducted at a fixed voltage of 60 V for 120 s on aluminized Inconel 738-LC, and then heat treated at 1100{sup o}C for 4 h in air atmosphere. The coating morphology and elemental distribution were studied using scanning electron microscopy. It was observed that suspension media have an important effect on the quality of the final product. Acetyl acetone showed better dispersion of particles than the other two media. Consequently, deposition from acetyl acetone resulted in uniform and crack-free layers while those from ethanol and acetone were completely non-uniform due to agglomeration and low viscosity, respectively.

  11. Morphology of Diamond Layers Grown on Different Facets of Single Crystal Diamond Substrates by a Microwave Plasma CVD in CH4-H2-N2 Gas Mixtures

    Directory of Open Access Journals (Sweden)

    Evgeny E. Ashkinazi

    2017-06-01

    Full Text Available Epitaxial growth of diamond films on different facets of synthetic IIa-type single crystal (SC high-pressure high temperature (HPHT diamond substrate by a microwave plasma CVD in CH4-H2-N2 gas mixture with the high concentration (4% of nitrogen is studied. A beveled SC diamond embraced with low-index {100}, {110}, {111}, {211}, and {311} faces was used as the substrate. Only the {100} face is found to sustain homoepitaxial growth at the present experimental parameters, while nanocrystalline diamond (NCD films are produced on other planes. This observation is important for the choice of appropriate growth parameters, in particular, for the production of bi-layer or multilayer NCD-on-microcrystalline diamond (MCD superhard coatings on tools when the deposition of continuous conformal NCD film on all facet is required. The development of the film morphology with growth time is examined with SEM. The structure of hillocks, with or without polycrystalline aggregates, that appear on {100} face is analyzed, and the stress field (up to 0.4 GPa within the hillocks is evaluated based on high-resolution mapping of photoluminescence spectra of nitrogen-vacancy NV optical centers in the film.

  12. Thermal barrier coatings of rare earth materials deposited by electron beam-physical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Xu Zhenhua [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Graduate School of Chinese Academy of Sciences, Beijing 100039 (China); Beijing Institute of Aeronautical Materials, Department 5, P.O. Box 81-5, Beijing 100095 (China); He Limin, E-mail: he_limin@yahoo.co [Beijing Institute of Aeronautical Materials, Department 5, P.O. Box 81-5, Beijing 100095 (China); Chen Xiaolong; Zhao Yu [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Graduate School of Chinese Academy of Sciences, Beijing 100039 (China); Cao Xueqiang, E-mail: xcao@ciac.jl.c [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2010-10-15

    Thermal barrier coatings (TBCs) have very important applications in gas turbines for higher thermal efficiency and protection of components at high temperature. TBCs of rare earth materials such as lanthanum zirconate (La{sub 2}Zr{sub 2}O{sub 7}, LZ), lanthanum cerate (La{sub 2}Ce{sub 2}O{sub 7}, LC), lanthanum cerium zirconate (La{sub 2}(Zr{sub 0.7}Ce{sub 0.3}){sub 2}O{sub 7}, LZ7C3) were prepared by electron beam-physical vapor deposition (EB-PVD). The composition, crystal structure, cross-sectional morphology and cyclic oxidation behavior of these coatings were studied. These coatings have partially deviated from their original compositions due to the different evaporation rates of oxides, and the deviation could be reduced by properly controlling the deposition condition. A double ceramic layer-thermal barrier coatings (DCL-TBCs) of LZ7C3 and LC could also be deposited with a single LZ7C3 ingot by properly controlling the deposition energy. LaAlO{sub 3} is formed due to the chemical reaction between LC and Al{sub 2}O{sub 3} in the thermally grown oxide (TGO) layer. The failure of DCL-TBCs is a result of the sintering-induced of LZ7C3 coating and the chemical incompatibility of LC and TGO. Since no single material that has been studied so far satisfies all the requirements for high temperature applications, DCL-TBCs are an important development direction of TBCs.

  13. Manufacturing and coating of optical components for the EnMAP hyperspectral imager

    Science.gov (United States)

    Schürmann, M.; Gäbler, D.; Schlegel, R.; Schwinde, S.; Peschel, T.; Damm, C.; Jende, R.; Kinast, J.; Müller, S.; Beier, M.; Risse, S.; Sang, B.; Glier, M.; Bittner, H.; Erhard, M.

    2016-07-01

    The optical system of the hyperspectral imager of the Environmental Mapping and Analysis Program (EnMAP) consists of a three-mirror anastigmat (TMA) and two independent spectrometers working in the VNIR and SWIR spectral range, respectively. The VNIR spectrometer includes a spherical NiP coated Al6061 mirror that has been ultra-precisely diamond turned and finally coated with protected silver as well as four curved fused silica (FS) and flint glass (SF6) prisms, respectively, each with broadband antireflection (AR) coating, while the backs of the two outer prisms are coated with a high-reflective coating. For AR coating, plasma ion assisted deposition (PIAD) has been used; the high-reflective enhanced Ag-coating on the backside has been deposited by magnetron sputtering. The SWIR spectrometer contains four plane and spherical gold-coated mirrors, respectively, and two curved FS prisms with a broadband antireflection coating. Details about the ultra-precise manufacturing of metal mirrors and prisms as well as their coating are presented in this work.

  14. Development of diamond thin film-based alpha particle detectors for online assay of plutonium content in corrosive liquid medium

    International Nuclear Information System (INIS)

    Nuwad, J.; Jain, Dheeraj; Manoj, N.; Sudarsan, V.; Panja, S.; Dhami, P.S.

    2014-01-01

    In the present work, diamond thin films were prepared using microwave plasma chemical vapor deposition (MPCVD) method and characterized using XRD, OES, SEM, Raman spectroscopy and I-V techniques. These films were subjected to annealing and chemical cleaning for further improving the film quality. Surface metallization was obtained by gold deposition using PVD. These films were configured in semiconductor-insulator-metal heterostructure and mounted in SS shells. Gold coated growth surface (detector's active area) was sealed by chemical resistant sealing. Suitable bias was applied between the front and back electrical contacts to enable charge collection generated upon alpha particle interaction with diamond. The photograph of developed detector in the lab is shown

  15. Deposition of selenium coatings on beryllium foils. Revision 1

    International Nuclear Information System (INIS)

    Erikson, E.D.; Tassano, P.L.; Reiss, R.H.; Griggs, G.E.

    1984-01-01

    A technique for preparing selenium films on 50.8 micrometers thick beryllium foils is described. The selenium was deposited in vacuum from a resistance heated evaporation source. A water-cooled enclosure was used to minimize contamination of the vacuum system and to reduce the exposure of personnel to toxic and obnoxious materials. Profilometry measurements of the coatings indicated selenium thicknesses of 5.5, 12.9, 37.5, 49.8 and 74.5 micrometers. The control of deposition rate and of coating thickness was facilitated using a commercially available closed-loop programmable deposition controller. The x-ray transmission of the coated substrates was measured using a tritiated zirconium source. The transmissivities of the film/substrate combination are presented for the range of energies from 4 to 20 keV

  16. PREPARING OF THE CHAMELEON COATING BY THE ION JET DEPOSITION METHOD

    Directory of Open Access Journals (Sweden)

    Jakub Skocdopole

    2017-07-01

    Full Text Available Preparation of chameleon coatings using an Ionized Jet Deposition (IJD technique is reported in the present paper. IJD is a new flexible method for thin film deposition developed by Noivion, Srl. The chameleon coatings are thin films characterised by a distinct change of their tribological properties according to the external conditions. The deposited films of SiC and TiN materials were examined by the Raman spectroscopy, SEM and XPS. The results of the Raman spectroscopy have proved an amorphous structure of SiC films. The data from XPS on TiN films have shown that the films are heavily oxidized, but also prove that the films are composed of TiN and pure Ti. The SEM provided information about the size of grains and particles constituting the deposited films, which is important for tribological properties of the films. Deposition of the chameleon coating is very complex problem and IJD could be ideal method for preparation of this coating.

  17. Hot Deformation Behavior and Processing Maps of Diamond/Cu Composites

    Science.gov (United States)

    Zhang, Hongdi; Liu, Yue; Zhang, Fan; Zhang, Di; Zhu, Hanxing; Fan, Tongxiang

    2018-06-01

    The hot deformation behaviors of 50 vol pct uncoated and Cr-coated diamond/Cu composites were investigated using hot isothermal compression tests under the temperature and strain rate ranging from 1073 K to 1273 K (800 °C to 1000 °C) and from 0.001 to 5 s-1, respectively. Dynamic recrystallization was determined to be the primary restoration mechanism during deformation. The Cr3C2 coating enhanced the interfacial bonding and resulted in a larger flow stress for the Cr-coated diamond/Cu composites. Moreover, the enhanced interfacial affinity led to a higher activation energy for the Cr-coated diamond/Cu composites (238 kJ/mol) than for their uncoated counterparts (205 kJ/mol). The strain-rate-dependent constitutive equations of the diamond/Cu composites were derived based on the Arrhenius model, and a high correlation ( R = 0.99) was observed between the calculated flow stresses and experimental data. With the help of processing maps, hot extrusions were realized at 1123 K/0.01 s-1 and 1153 K/0.01 s-1 (850 °C/0.01 s-1 and 880 °C/0.01 s-1) for the uncoated and coated diamond/Cu composites, respectively. The combination of interface optimization and hot extrusion led to increases of the density and thermal conductivity, thereby providing a promising route for the fabrication of diamond/Cu composites.

  18. Phase transitions of doped carbon in CrCN coatings with modified mechanical and tribological properties via filtered cathodic vacuum arc deposition

    International Nuclear Information System (INIS)

    Guan, J.J.; Wang, H.Q.; Qin, L.Z.; Liao, B.; Liang, H.; Li, B.

    2017-01-01

    The CrCN coatings were fabricated onto Si (1 1 1) wafers and SUS304 stainless steel plates using filtered cathodic vacuum arc deposition (FCVAD) technique under different flow ratios of N_2/C_2H_2 gas mixture. The morphology, crystalline structure and chemical composition of the coatings were characterized. It was found that the grain size reduce with increasing carbon content, which makes the CrCN coatings refined and smooth. The quasi-one-dimensional carbolite phase was also found in CrN host lattice with C_2H_2 content ranging from 5% to 20%, and it will be evolved into amorphous carbon and amorphous CN_x phases as C_2H_2 content exceeds 20%. Moreover, we examined the mechanical and tribological properties of the CrCN coatings, and the experimental results confirmed that the friction coefficient of the coatings descend to the lowest value as 0.39 with 30% C_2H_2 content, due to the graphite (sp"2 C−C) phase embed in CrN host lattice; while the chromium carbon (Cr_3C_2) and diamond (sp"3 C−C) phases may give rise to the increase of the coating hardness with the highest value at 23.97 GPa under 20% C_2H_2 content.

  19. Phase transitions of doped carbon in CrCN coatings with modified mechanical and tribological properties via filtered cathodic vacuum arc deposition

    Science.gov (United States)

    Guan, J. J.; Wang, H. Q.; Qin, L. Z.; Liao, B.; Liang, H.; Li, B.

    2017-04-01

    The CrCN coatings were fabricated onto Si (1 1 1) wafers and SUS304 stainless steel plates using filtered cathodic vacuum arc deposition (FCVAD) technique under different flow ratios of N2/C2H2 gas mixture. The morphology, crystalline structure and chemical composition of the coatings were characterized. It was found that the grain size reduce with increasing carbon content, which makes the CrCN coatings refined and smooth. The quasi-one-dimensional carbolite phase was also found in CrN host lattice with C2H2 content ranging from 5% to 20%, and it will be evolved into amorphous carbon and amorphous CNx phases as C2H2 content exceeds 20%. Moreover, we examined the mechanical and tribological properties of the CrCN coatings, and the experimental results confirmed that the friction coefficient of the coatings descend to the lowest value as 0.39 with 30% C2H2 content, due to the graphite (sp2 Csbnd C) phase embed in CrN host lattice; while the chromium carbon (Cr3C2) and diamond (sp3 Csbnd C) phases may give rise to the increase of the coating hardness with the highest value at 23.97 GPa under 20% C2H2 content.

  20. Laser diagnostics of a diamond depositing chemical vapour deposition gas-phase environment

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James Anthony

    2002-07-01

    Studies have been carried out to understand the gas-phase chemistry underpinning diamond deposition in hot filament and DC-arcjet chemical vapour deposition (CVD) systems. Resonance enhanced Multiphoton lonisation (REMPI) techniques were used to measure the relative H atom and CH{sub 3} radical number densities and local gas temperatures prevalent in a hot filament reactor, operating on Ch{sub 4}/H{sub 2} and C{sub 2}H{sub 2}/H{sub 2} gas mixtures. These results were compared to a 3D-computer simulation, and hence provided an insight into the nature of the gas-phase chemistry with particular reference to C{sub 2}{yields}C{sub 1} species conversion. Similar experimental and theoretical studies were also carried out to explain the chemistry involved in NH{sub 3}/CH{sub 4}/H{sub 2} and N{sub 2}/CH{sub 4}/H{sub 2} gas mixtures. It was demonstrated that the reactive nature of the filament surface was dependent on the addition of NH{sub 3}, influencing atomic hydrogen production, and thus the H/C/N gas-phase chemistry. Studies of the DC-arcjet diamond CVD reactor consisted of optical emission spectroscopic studies of the plume during deposition from an Ar/H{sub 2}/CH{sub 4}/N{sub 2} gas mixture. Spatially resolved species emission intensity maps were obtained for C{sub 2}(d{yields}a), CN(B{yields}X) and H{sub {beta}} from Abel-inverted datasets. The C{sub 2}(d{yields}a) and CN(B{yields}X) emission intensity maps both show local maxima near the substrate surface. SEM and Laser Raman analyses indicate that N{sub 2} additions lead to a reduction in film quality and growth rate. Photoluminescence and SIMS analyses of the grown films provide conclusive evidence of nitrogen incorporation (as chemically bonded CN). Absolute column densities of C{sub 2}(a) in a DC-arcjet reactor operating on an Ar/H{sub 2}/CH{sub 4} gas mixture, were measured using Cavity ring down spectroscopy. Simulations of the measured C{sub 2}(v=0) transition revealed a rotational temperature of {approx

  1. Compositionally modulated multilayer diamond-like carbon coatings with AlTiSi multi-doping by reactive high power impulse magnetron sputtering

    Science.gov (United States)

    Dai, Wei; Gao, Xiang; Liu, Jingmao; Kwon, Se-Hun; Wang, Qimin

    2017-12-01

    Diamond-like carbon (DLC) coatings with AlTiSi multi-doping were prepared by a reactive high power impulse magnetron sputtering with using a gas mixture of Ar and C2H2 as precursor. The composition, microstructure, compressive stress, and mechanical property of the as-deposited DLC coatings were studied systemically by using SEM, XPS, TEM, Raman spectrum, stress-tester, and nanoindentation as a function of the Ar fraction. The results show that the doping concentrations of the Al, Ti and Si atoms increased as the Ar fraction increased. The doped Ti and Si preferred to bond with C while the doped Al mainly existed in oxidation state without bonding with C. As the doping concentrations increased, TiC carbide nanocrystals were formed in the DLC matrix. The microstructure of coatings changed from an amorphous feature dominant AlTiSi-DLC to a carbide nanocomposite AlTiSi-DLC with TiC nanoparticles embedding. In addition, the coatings exhibited the compositionally modulated multilayer consisting of alternate Al-rich layer and Al-poor layer due to the rotation of the substrate holder and the diffusion behavior of the doped Al which tended to separate from C and diffuse towards the DLC matrix surface owing to its weak interactions with C. The periodic Al-rich layer can effectively release the compressive stress of the coatings. On the other hand, the hard TiC nanoparticles were conducive to the hardness of the coatings. Consequently, the DLC coatings with relatively low residual stress and high hardness could be acquired successfully through AlTiSi multi-doping. It is believed that the AlCrSi multi-doping may be a good way for improving the comprehensive properties of the DLC coatings. In addition, we believe that the DLC coatings with Al-rich multilayered structure have a high oxidation resistance, which allows the DLC coatings application in high temperature environment.

  2. Preliminary viability studies of fibroblastic cells cultured on microcrystalline and nanocrystalline diamonds produced by chemical vapour deposition method

    Directory of Open Access Journals (Sweden)

    Ana Amélia Rodrigues

    2013-02-01

    Full Text Available Implant materials used in orthopedics surgery have demonstrated some disadvantages, such as metallic corrosion processes, generation of wear particles, inflammation reactions and bone reabsorption in the implant region. The diamond produced through hot-filament chemical vapour deposition method is a new potential biomedical material due to its chemical inertness, extreme hardness and low coefficient of friction. In the present study we analysis two samples: the microcrystalline diamond and the nanocrystalline diamond. The aim of this study was to evaluate the surface properties of the diamond samples by scanning electron microscopy, Raman spectroscopy and atomic force microscopy. Cell viability and morphology were assessed using thiazolyl blue tetrazolium bromide, cytochemical assay and scanning electron microscopy, respectively. The results revealed that the two samples did not interfere in the cell viability, however the proliferation of fibroblasts cells observed was comparatively higher with the nanocrystalline diamond.

  3. Roll-to-roll vacuum deposition of barrier coatings

    CERN Document Server

    Bishop, Charles A

    2015-01-01

    It is intended that the book will be a practical guide to provide any reader with the basic information to help them understand what is necessary in order to produce a good barrier coated web or to improve the quality of any existing barrier product. After providing an introduction, where the terminology is outlined and some of the science is given (keeping the mathematics to a minimum), including barrier testing methods, the vacuum deposition process will be described. In theory a thin layer of metal or glass-like material should be enough to convert any polymer film into a perfect barrier material. The reality is that all barrier coatings have their performance limited by the defects in the coating. This book looks at the whole process from the source materials through to the post deposition handling of the coated material. This holistic view of the vacuum coating process provides a description of the common sources of defects and includes the possible methods of limiting the defects. This enables readers...

  4. Study of carbide-forming element interlayers for diamond nucleation and growth on silicon and WC-Co substrates

    International Nuclear Information System (INIS)

    Tang, Y.; Li, Y.S.; Yang, Q.; Hirose, A.

    2010-01-01

    Diamond nucleation and growth on several typical carbide-forming elements (CFE) (Ti, Cr and W) coated Si and WC-Co substrates were studied. The ion beam sputtered CFE interlayers show an amorphous/nanocrystalline microstructure. The diamond formed on the CFE coated substrates shows higher nucleation density and rate and finer grain structure than on uncoated substrates. Consequently, nanocrystalline diamond thin films can be formed on the CFE coated substrates under conventional microcrystalline diamond growth conditions. Among the three tested CFE interlayers, diamond has the highest nucleation density and rate on W layer and the lowest on Ti layer. The diamond nucleation density and rate on CFE coated WC-Co are much higher than those on widely used metal nitride coated WC-Co.

  5. Diamond Pixel Detectors and 3D Diamond Devices

    International Nuclear Information System (INIS)

    Venturi, N.

    2016-01-01

    Results from detectors of poly-crystalline chemical vapour deposited (pCVD) diamond are presented. These include the first analysis of data of the ATLAS Diamond Beam Monitor (DBM). The DBM module consists of pCVD diamond sensors instrumented with pixellated FE-I4 front-end electronics. Six diamond telescopes, each with three modules, are placed symmetrically around the ATLAS interaction point. The DBM tracking capabilities allow it to discriminate between particles coming from the interaction point and background particles passing through the ATLAS detector. Also, analysis of test beam data of pCVD DBM modules are presented. A new low threshold tuning algorithm based on noise occupancy was developed which increases the DBM module signal to noise ratio significantly. Finally first results from prototypes of a novel detector using pCVD diamond and resistive electrodes in the bulk, forming a 3D diamond device, are discussed. 3D devices based on pCVD diamond were successfully tested with test beams at CERN. The measured charge is compared to that of a strip detector mounted on the same pCVD diamond showing that the 3D device collects significantly more charge than the planar device.

  6. A review of hydroxyapatite-based coating techniques: Sol-gel and electrochemical depositions on biocompatible metals.

    Science.gov (United States)

    Asri, R I M; Harun, W S W; Hassan, M A; Ghani, S A C; Buyong, Z

    2016-04-01

    New promising techniques for depositing biocompatible hydroxyapatite-based coatings on biocompatible metal substrates for biomedical applications have continuously been exploited for more than two decades. Currently, various experimental deposition processes have been employed. In this review, the two most frequently used deposition processes will be discussed: a sol-gel dip coating and an electrochemical deposition. This study deliberates the surface morphologies and chemical composition, mechanical performance and biological responses of sol-gel dip coating as well as the electrochemical deposition for two different sample conditions, with and without coating. The review shows that sol-gel dip coatings and electrochemical deposition were able to obtain the uniform and homogeneous coating thickness and high adherent biocompatible coatings even in complex shapes. It has been accepted that both coating techniques improve bone strength and initial osseointegration rate. The main advantages and limitations of those techniques of hydroxyapatite-based coatings are presented. Furthermore, the most significant challenges and critical issues are also highlighted. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Thermal shock behavior of platinum aluminide bond coat/electron beam-physical vapor deposited thermal barrier coatings

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Zhenhua, E-mail: zhxuciac@163.com [Beijing Institute of Aeronautical Materials, Department 5, P.O. Box 81-5, Beijing 100095 (China); Dai, Jianwei [Beijing Institute of Aeronautical Materials, Department 5, P.O. Box 81-5, Beijing 100095 (China); Niu, Jing [Shenyang Liming Aero-engine (Group) Corporation Ltd., Institute of Metallurgical Technology, Technical Center, Shengyang 110043 (China); Li, Na; Huang, Guanghong; He, Limin [Beijing Institute of Aeronautical Materials, Department 5, P.O. Box 81-5, Beijing 100095 (China)

    2014-12-25

    Highlights: • TBCs of (Ni, Pt)Al bond coat with grit blasting process and YSZ ceramic coating. • Grain boundary ridges are the sites for spallation damage initiation in TBCs. • Ridges removed, cavities formation appeared and the damage initiation deteriorated. • Damage initiation and progression at interface lead to a buckling failure. - Abstract: Thermal barrier coating systems (TBCs) including of chemical vapor deposited (Ni, Pt)Al bond coat with grit blasting process and electron beam physical vapor deposited Y{sub 2}O{sub 3}-stabilized-ZrO{sub 2} (YSZ) ceramic coating were investigated. The phase structures, surface and cross-sectional morphologies, thermal shock behaviors and residual stresses of the coatings were studied in detail. Grain boundary ridges still remain on the surface of bond coat prior to the deposition of the ceramic coating, which are shown to be the major sites for spallation damage initiation in TBCs. When these ridges are mostly removed, they appear some of cavities formation and then the damage initiation mode is deteriorated. Damage initiation and progression occurs at the bond coat to thermally grown oxide (TGO) interface leading to a buckling failure behavior. A buckle failure once started may be arrested when it runs into a region of high bond coat to TGO interface toughness. Thus, complete failure requires further loss in toughness of the bond coat to TGO interface during cooling. The suppressed cavities formation, the removed ridges at the grain boundaries, the relative high TGO to bond coat interface toughness, the uniform growth behavior of TGO thickening and the lower of the residual stress are the primary factors for prolonging the lifetime of TBCs.

  8. Deposition of hybrid organic-inorganic composite coatings using an atmospheric plasma jet system.

    Science.gov (United States)

    Dembele, Amidou; Rahman, Mahfujur; Reid, Ian; Twomey, Barry; MacElroy, J M Don; Dowling, Denis P

    2011-10-01

    The objective of this study is to investigate the influence of alcohol addition on the incorporation of metal oxide nanoparticles into nm thick siloxane coatings. Titanium oxide (TiO2) nanoparticles with diameters of 30-80 nm were incorporated into an atmospheric plasma deposited tetramethylorthosilicate (TMOS) siloxane coating. The TMOS/TiO2 coating was deposited using the atmospheric plasma jet system known as PlasmaStream. In this system the liquid precursor/nanoparticle mixture is nebulised into the plasma. It was observed that prior to being nebulised the TiO2 particles agglomerated and settled over time in the TMOS/TiO2 mixture. In order to obtain a more stable nanoparticle/TMOS suspension the addition of the alcohols methanol, octanol and pentanol to this mixture was investigated. The addition of each of these alcohols was found to stabilise the nanoparticle suspension. The effect of the alcohol was therefore assessed with respect to the properties of the deposited coatings. It was observed that coatings deposited from TMOS/TiO2, with and without the addition of methanol were broadly similar. In contrast the coatings deposited with octanol and pentanol addition to the TMOS/TiO2 mixture were significantly thicker, for a given set of deposition parameters and were also more homogeneous. This would indicate that the alcohol precursor was incorporated into the plasma polymerised siloxane. The incorporation of the organic functionality from the alcohols was confirmed from FTIR spectra of the coatings. The difference in behaviour with alcohol type is likely to be due to the lower boiling point of methanol (65 degrees C), which is lower than the maximum plasma temperature measured at the jet orifice (77 degrees C). This temperature is significantly lower than the 196 degrees C and 136 degrees C boiling points of octanol and pentanol respectively. The friction of the coatings was determined using the Pin-on-disc technique. The more organic coatings deposited with

  9. Influence of the deposition geometry on the microstructure of sputter-deposited V-Al-C-N coatings

    Energy Technology Data Exchange (ETDEWEB)

    Darma, Susan; Krause, Baerbel; Doyle, Stephen; Mangold, Stefan; Baumbach, Tilo [ISS, Karlsruher Institut fuer Technologie (Germany); Ulrich, Sven; Stueber, Michael [IAM-AWP, Karlsruher Institut fuer Technologie (Germany)

    2012-07-01

    Multi-element hard coating materials such as V-Al-C-N are of great interest for many technological applications. Their mechanical properties depend on the composition and microstructure of the coating. In order to determine the optimum composition and deposition conditions of these complex materials, many samples are required. One powerful tool for reducing the number of experiments is based on the so-called combinatorial approach for thin film deposition: many different thin film samples can be realized simultaneously, exploiting the deposition gradient resulting from codeposition of several materials. We will present an X-ray diffraction study of the influence of the deposition geometry on the microstructure of V-Al-C-N coatings. The films were deposited by reactive RF magnetron sputtering from a segmented target composed of AlN and VC. Synchrotron radiation measurements where performed at the beamline PDIFF at ANKA. Significant texture changes were observed which can be attributed to the deposition geometry, as verified by calculations of the flux distribution. We conclude that codeposition can accelerate significantly the screening of new materials, under the condition that the desired property is not significantly influenced by the microstructural changes due to the deposition geometry.

  10. Comparative evaluation of CVD diamond technologies

    Energy Technology Data Exchange (ETDEWEB)

    Anthony, T.R. [General Electric Corporate Research & Development Center, Schenectady, NY (United States)

    1993-01-01

    Chemical vapor deposition (CVD) of diamonds occurs from hydrogen-hydrocarbon gas mixtures in the presence of atomic hydrogen at subatmospheric pressures. Most CVD methods are based on different means of generating and transporting atomic hydrogen in a particular system. Evaluation of these different techniques involves their capital costs, material costs, energy costs, labor costs and the type and quality of diamond that they produce. Currently, there is no universal agreement on which is the best technique and technique selection has been largely driven by the professional background of the user as well as the particular application of interest. This article discusses the criteria for evaluating a process for low-pressure deposition of diamond. Next, a brief history of low-pressure diamond synthesis is reviewed. Several specific processes are addressed, including the hot filament process, hot filament electron-assisted chemical vapor deposition, and plasma generation of atomic hydrogen by glow discharge, microwave discharge, low pressure radio frequency discharge, high pressure DC discharge, high pressure microwave discharge jets, high pressure RF discharge, and high and low pressure flames. Other types of diamond deposition methods are also evaluated. 101 refs., 15 figs.

  11. The interaction between diamond like carbon (DLC coatings and ionic liquids under boundary lubrication conditions

    Directory of Open Access Journals (Sweden)

    K. Milewski

    2017-01-01

    Full Text Available The aim of the study was to analyse antiwear DLC coatings produced by physical vapour deposition. The a-C:H coatings were deposited on steel elements designed to operate under friction conditions. The coating structure was studied by observing the surface topography with a scanning electron microscope (SEM and a profilometer. The friction and wear properties of the coatings were examined using a ball-on-disc tribotester. The lubricants tested were two types of ionic liquids (1-butyl-3-methylimidazolium tetrafluoroborate and trihexyltetradecylphosphonium bis(trifluoromethy-lsulphonyl amide. The experimental data was used to select ionic liquids with the best tribological properties to operate under lubricated friction conditions and interact with DLC coatings.

  12. Long length coated conductor fabrication by inclined substrate deposition and evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Prusseit, W [THEVA Duennschichttechnik GmbH, Rote-Kreuz-Str. 8, 85737 Ismaning (Germany); Hoffmann, C [THEVA Duennschichttechnik GmbH, Rote-Kreuz-Str. 8, 85737 Ismaning (Germany); Nemetschek, R [THEVA Duennschichttechnik GmbH, Rote-Kreuz-Str. 8, 85737 Ismaning (Germany); Sigl, G [THEVA Duennschichttechnik GmbH, Rote-Kreuz-Str. 8, 85737 Ismaning (Germany); Handke, J [THEVA Duennschichttechnik GmbH, Rote-Kreuz-Str. 8, 85737 Ismaning (Germany); Luemkemann, A [Technical University Munich, James- Franck-Str. 1, 85748 Garching (Germany); Kinder, H [Technical University Munich, James- Franck-Str. 1, 85748 Garching (Germany)

    2006-06-01

    The commercial development of coated conductors is rapidly progressing. As a result we present an economic route to produce second generation HTS tape from the initial substrate preparation to the final metal coating. The most important and technically challenging steps are the deposition of an oriented buffer layer and the superconductor film in a reel-to-reel configuration. New evaporation techniques have been developed to enable reliable, high rate tape coating. Highly oriented MgO - buffer layers are realized by inclined substrate deposition (ISD) and DyBCO is deposited by simple e-gun evaporation yielding critical currents beyond 200 A/cm. Coated conductors have been fabricated up to 40 m length and are currently tested in a variety of applications.

  13. Superhard carbon film deposition by means of Laser-Arco {sup registered} on the way from the laboratory into the industrial series coating; Abscheidung superharter Kohlenstoffschichten mittels Laser-Arco {sup registered} auf dem Weg vom Labor in die industrielle Serienfertigung

    Energy Technology Data Exchange (ETDEWEB)

    Scheibe, Hans-Joachim; Leonhardt, Michael; Leson, Andreas; Meyer, Carl-Friedrich; Stucky, Thomas; Weihnacht, Volker [Fraunhofer-Institut fuer Werkstoff- und Strahltechnik (IWS), Dresden (Germany)

    2008-12-15

    Diamond-like carbon films (DLC) are more and more applied as wear protection coatings for components and tools due to their unique combination of high hardness, low friction and sticking tendency to metallic counter bodies. Up to now applied DLC films are hydrogen containing (a-C:H) or metal carbon films (Me-C:H) deposited by a plasma assisted CVD process from carbon-hydrogen gas mixtures. Their wide industrial effort results from that the can be deposited with slowly modified coating machines for classical hard coating (e.g. TiN or CrN). A new generation DLC films are the hydrogen-free ta-C films (ta-C = tetrahedral bounded amorphous carbon) with a between two and three-times higher hardness and with a resulting higher wear resistance under extreme condition than classical DLC films. They have excellent emergency running properties at lubrication break down. Their industrial application is more difficult due to that they cannot deposited with modified coating machines for classical hard and DLC coating and a new technology with corresponding equipment was not available up to now. The laser controlled, pulsed arc deposition technology (Laser-Arco {sup registered}) of the Fraunhofer IWS Dresden has this potential. In kind of a Laser-Arc-Module-source the ta-C film deposition can be integrated in every industrial used deposition machine. (orig.)

  14. Plasmochemical modification of aluminum-zinc alloys using NH{sub 3}-Ar atmosphere with anti-wear coatings deposition

    Energy Technology Data Exchange (ETDEWEB)

    Kyzioł, Karol, E-mail: kyziol@agh.edu.pl [Faculty of Materials Science and Ceramics, AGH University of Science and Technology, A. Mickiewicza Av. 30, 30 059 Kraków (Poland); Koper, Katarzyna [Faculty of Materials Science and Ceramics, AGH University of Science and Technology, A. Mickiewicza Av. 30, 30 059 Kraków (Poland); Kaczmarek, Łukasz [Institute of Materials Science and Engineering, Lodz University of Technology, Stefanowskiego Str. 1/15, 90 924 Łódz (Poland); Grzesik, Zbigniew [Faculty of Materials Science and Ceramics, AGH University of Science and Technology, A. Mickiewicza Av. 30, 30 059 Kraków (Poland)

    2017-03-01

    This paper constitutes a continuation of studies on modification technologies for 7075 series aluminum alloys (Al-Zn) in plasmochemical conditions using the RF CVD (Radio-Frequency Chemical Vapor Deposition) method. This technique is simultaneously the second stage of alloy ageing. The presented results concern optimization of alloy surface modification using N{sup +} ions (in NH{sub 3} or NH{sub 3}/Ar atmosphere) before obtaining a DLC (Diamond-Like Carbon) layer doped with Si and N. From the results it can be concluded that the most profitable mechanical properties (H, ca. 12 GPa and E, ca. 115 GPa) are obtained when the SiCNH coating process is preceded by Al-Zn alloy surface modification with nitrogen ions. These ions are provided by a flowing NH{sub 3} and Ar gas mixture (1:1 ratio). In these process conditions, the lowest tribological wear of the surface is also observed. Furthermore, the obtained coating exhibits a fine-grained structure. - Highlights: • Surface properties of Al-Zn alloy after plasma processes are investigated. • Modification in a RF reactor was the second stage of ageing. • The N{sup +} ion treatments of aluminum substrates was justified. • SiCNH coatings obtained on Al alloys significantly improve mechanical parameters.

  15. Carbon-Based Wear Coatings: Properties and Applications

    Science.gov (United States)

    Miyoshi, Kazuhisa

    2003-01-01

    and friction; thermal conductivity; chemical and thermal inertness; corrosion and wear resistance; radiation resistance and biocompatibility; electronic, acoustic, and electrochemical characteristics; and environmental compatibility. These properties make diamond attractive for a wide range of diverse applications. In particular, chemical-vapor-deposited (CVD) diamond coatings offer a broad potential, since size and cost are not as limiting. The production of large, superhard diamond films or sheets at low cost make designer materials possible. This presentation is divided into two sections: properties and applications of hard coatings. The first section is concerned with the fundamental properties of the surfaces of CVD diamonds and related materials. The surface properties of hard coatings with favorable coefficients of friction (less than or equal to 0.1) and dimensional wear coefficients (less than or equal to 10(exp -6) cubic millimeters/N.m) in specific environments are discussed. The second section is devoted to applications. Examples of actual, successful applications and of potential challenging applications of the coatings.such as CVD diamond, diamondlike carbon, and cubic boron nitride-are described. Cutting tools coated with CVD diamond are of immediate commercial interest. Other applications, such as microelectromechanical systems (MEMS), valves, and bearings of CVD diamond, are being developed, but at a slow pace. There is a continually growing interest in commercializing diamondlike carbon for wear parts applications, such as biomedical parts and implants, forming dies, transport guides, magnetic tapes and disks, valves, and gears. Cubic boron nitride films are receiving attention because they can be used on tools to machine ferrous materials or on wear parts in sliding contact with ferrous materials.

  16. Large area IBAD deposition of Zn-alloys in the coil coating mode

    International Nuclear Information System (INIS)

    Wolf, G.K.; Preiss, G.; Muenz, R.; Guzman, L.

    2001-01-01

    In the last years many studies on IBAD coatings on metals and insulators for wear reduction and corrosion protection have been published. However the IBAD deposition of larger areas (>10 x 10 cm) is still a major problem. Therefore we have developed a coil coater running inside the IBAD deposition chamber and allowing very flexible deposition modes. Single layers, multilayers and alloys can be deposited under ion bombardment on substrates up to 30 by 40 cm or on metal and polymer strips 30 cm wide. A number of examples dealing with Zn-alloy coatings on low alloy steel are reported: pure Zn-coatings were compared with Zn/Ti-alloys Zn/Cr-alloys and Zn/Mn-alloys. In some cases also multilayers of the different metals were studied in the static and dynamic operation mode. The coatings had a thickness of 2-8 μm and their corrosion behaviour was investigated by salt spray tests. The microstructure of the coatings was studied by electron microscopy and EDX-depth profiling. The behaviour of the coating/substrate system is discussed in comparison with 'state-of-the-art' Zn-coatings produced by electrogalvanizing. Generally speaking the performance of the optimized coatings was as good as or better than the electrogalvanized standard

  17. Diamond Nucleation Using Polyethene

    Science.gov (United States)

    Morell, Gerardo (Inventor); Makarov, Vladimir (Inventor); Varshney, Deepak (Inventor); Weiner, Brad (Inventor)

    2013-01-01

    The invention presents a simple, non-destructive and non-abrasive method of diamond nucleation using polyethene. It particularly describes the nucleation of diamond on an electrically viable substrate surface using polyethene via chemical vapor deposition (CVD) technique in a gaseous environment.

  18. Electrophoretic deposition of sol-gel-derived ceramic coatings

    International Nuclear Information System (INIS)

    Zhang, Y.; Crooks, R.M.

    1992-01-01

    In this paper the physical, optical, and chemical characteristics of electrophoretically and dip-coated sol-gel ceramic films are compared. The results indicate that electrophoresis may allow a higher level of control over the chemistry and structure of ceramic coatings than dip-coating techniques. For example, controlled-thickness sol-gel coatings can be prepared by adjusting the deposition time or voltage. Additionally, electrophoretic coatings can be prepared in a four-component alumino-borosilicate sol display interesting optical characteristics. For example, the ellipsometrically-measured refractive indices of electrophoretic coatings are higher than the refractive indices of dip-coated films cast from identical sols, and they are also higher than any of the individual sol components. This result suggests that there are physical and/or chemical differences between films prepared by dip-coating and electrophoresis

  19. Influence of electroformation regime on the specific properties of cobalt oxide‒platinum composite films deposited on conductive diamond

    Energy Technology Data Exchange (ETDEWEB)

    Spătaru, Tanţa; Osiceanu, Petre; Preda, Loredana; Munteanu, Cornel [Institute of Physical Chemistry “Ilie Murgulescu”, 202 Spl. Independenţei 060021, Bucharest (Romania); Spătaru, Nicolae, E-mail: nspataru@icf.ro [Institute of Physical Chemistry “Ilie Murgulescu”, 202 Spl. Independenţei 060021, Bucharest (Romania); Fujishima, Akira [Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku Tokyo 162-8601 (Japan)

    2014-04-01

    Two straightforward electrochemical methods were used in the present work for depositing cobalt oxide-platinum composite films on boron-doped diamond substrates in order to put into evidence the effect of the electroformation regime on the morphological and electrochemical features of these hybrid systems. The shift from potentiostatic to potentiodynamic deposition enabled not only a significant improvement of the Pt particles dispersion but also a much higher surface concentration of oxygenated species of platinum. For similar Co{sub 3}O{sub 4} and Pt loadings, the specific capacitance of the composite films deposited by cyclic voltammetry was with ca. 8% higher than that of the potentiostatically obtained ones. Additional advantage of potentiodynamic deposition is the improved resistance to fouling during methanol anodic oxidation of Pt particles, tentatively ascribed to the higher surface concentration of oxygenated species of platinum. - Highlights: • Cobalt oxide-platinum composite films were electrodeposited on conductive diamond. • Composite films formed by cyclic voltammetry exhibit enhanced specific capacitance. • Potentiodynamic deposition enables higher concentration of oxygenated Pt species. • Co{sub 3}O{sub 4}–Pt films prepared by cyclic voltammetry are less susceptible to CO poisoning.

  20. Vibration atomic layer deposition for conformal nanoparticle coating

    Energy Technology Data Exchange (ETDEWEB)

    Park, Suk Won; Woo Kim, Jun; Jong Choi, Hyung; Hyung Shim, Joon, E-mail: shimm@korea.ac.kr [School of Mechanical Engineering, Korea University, Seoul 136-701 (Korea, Republic of)

    2014-01-15

    A vibration atomic layer deposition reactor was developed for fabricating a conformal thin-film coating on nanosize particles. In this study, atomic layer deposition of 10–15-nm-thick Al{sub 2}O{sub 3} films was conducted on a high-surface-area acetylene black powder with particle diameters of 200–250 nm. Intense vibration during the deposition resulted in the effective separation of particles, overcoming the interparticle agglomeration force and enabling effective diffusion of the precursor into the powder chunk; this phenomenon led to the formation of a conformal film coating on the nanopowder particles. It was also confirmed that the atomic layer deposition Al{sub 2}O{sub 3} films initially grew on the high-surface-area acetylene black powder particles as discrete islands, presumably because chemisorption of the precursor and water occurred only on a few sites on the high-surface-area acetylene black powder surface. Relatively sluggish growth of the films during the initial atomic layer deposition cycles was identified from composition analysis.

  1. Friction and wear of TiCN coatings deposited by filtered arc

    International Nuclear Information System (INIS)

    Huang, S.W.; Ng, K.; Samandi, M.

    1998-01-01

    A series of macroparticle-free TiN, TiCN and TiC coatings were deposited on 316 austenitic stainless steel using a titanium target in a filtered arc deposition system and reactive mixtures of CH4 and N2 gases. The microhardness of the coatings were measured by using an Ultra Microhardness Indentation System (UMIS-2000). The wear and friction of the coatings were assessed under controlled test conditions in a pin-on-disc tribometer. The results show a significant increase in microhardness and wear resistance as the CH4 :N2 gas flow rate ratio is increased. At lower load (14N), all coatings exhibited low friction and wear. At higher load (25N), the higher carbon content TiCN and TiC coatings showed a much lower friction and wear compared to TiN and low carbon TiCN. The topographical examination of coatings and worn surfaces established that the self-lubricating effect of the carbonaceous particles condensed from the plasma during the deposition was primarily responsible for the low friction and wear regime. (authors)

  2. Sandblasting induced stress release and enhanced adhesion strength of diamond films deposited on austenite stainless steel

    Science.gov (United States)

    Li, Xiao; Ye, Jiansong; Zhang, Hangcheng; Feng, Tao; Chen, Jianqing; Hu, Xiaojun

    2017-08-01

    We firstly used sandblasting to treat austenite stainless steel and then deposited a Cr/CrN interlayer by close field unbalanced magnetron sputtering on it. After that, diamond films were prepared on the interlayer. It is found that the sandblasting process induces phase transition from austenite to martensite in the surface region of the stainless steel, which decreases thermal stress in diamond films due to lower thermal expansion coefficient of martensite phase compared with that of austenite phase. The sandblasting also makes stainless steel's surface rough and the Cr/CrN interlayer film inherits the rough surface. This decreases the carburization extent of the interlayer, increases nucleation density and modifies the stress distribution. Due to lower residual stress and small extent of the interlayer's carburization, the diamond film on sandblast treated austenite stainless steel shows enhanced adhesion strength.

  3. Amorphous boron coatings produced with vacuum arc deposition technology

    CERN Document Server

    Klepper, C C; Yadlowsky, E J; Carlson, E P; Keitz, M D; Williams, J M; Zuhr, R A; Poker, D B

    2002-01-01

    In principle, boron (B) as a material has many excellent surface properties, including corrosion resistance, very high hardness, refractory properties, and a strong tendency to bond with most substrates. The potential technological benefits of the material have not been realized, because it is difficult to deposit it as coatings. B is difficult to evaporate, does not sputter well, and cannot be thermally sprayed. In this article, first successful deposition results from a robust system, based on the vacuum (cathodic) arc technology, are reported. Adherent coatings have been produced on 1100 Al, CP-Ti, Ti-6Al-4V, 316 SS, hard chrome plate, and 52 100 steel. Composition and thickness analyses have been performed by Rutherford backscattering spectroscopy. Hardness (H) and modules (E) have been evaluated by nanoindentation. The coatings are very pure and have properties characteristic of B suboxides. A microhardness of up to 27 GPa has been measured on a 400-nm-thick film deposited on 52 100 steel, with a corresp...

  4. Improved stability of titanium based boron-doped chemical vapor deposited diamond thin-film electrode by modifying titanium substrate surface

    International Nuclear Information System (INIS)

    Lim, P.Y.; Lin, F.Y.; Shih, H.C.; Ralchenko, V.G.; Varnin, V.P.; Pleskov, Yu.V.; Hsu, S.F.; Chou, S.S.; Hsu, P.L.

    2008-01-01

    The film quality and electrochemical properties of BDD (boron-doped diamond) thin films grown by hot-filament chemical vapor deposition technique on titanium substrates that had been subjected to a range of pre-treatment processes were evaluated. The pre-roughened Ti-substrates are shown to support more adherent BDD films. It is evident that acid-etching the Ti-substrate involves surface hydrogenation that enhances nucleation and formation of diamond thereon. The prepared BDD film exhibits wide potential window and electrochemical reversibility. It also demonstrated a better long-term electrochemical stability based on the low variation in voltametric background current upon the exposing of the electrodes to repeated cycles of electrochemical metal deposition/stripping process

  5. Hard coatings on magnesium alloys by sputter deposition using a pulsed d.c. bias voltage

    Energy Technology Data Exchange (ETDEWEB)

    Reiners, G. [Bundesanstalt fuer Materialforschung und -pruefung, Berlin (Germany); Griepentrog, M. [Bundesanstalt fuer Materialforschung und -pruefung, Berlin (Germany)

    1995-12-01

    An increasing use of magnesium-based light-metal alloys for various industrial applications was predicted in different technological studies. Companies in different branches have developed machine parts made of magnesium alloys (e.g. cars, car engines, sewing and knitting machines). Hence, this work was started to evaluate the ability of hard coatings obtained by physical vapour deposition (PVD) in combination with coatings obtained by electrochemical deposition to protect magnesium alloys against wear and corrosion. TiN hard coatings were deposited onto magnesium alloys by unbalanced magnetron sputter deposition. A bipolar pulsed d.c. bias voltage was used to limit substrate temperatures to 180 C during deposition without considerable loss of microhardness and adhesion. Adhesion, hardness and load-carrying capacity of TiN coatings deposited directly onto magnesium alloys are compared with the corresponding values of TiN coatings deposited onto substrates which had been coated electroless with an Ni-P alloy interlayer prior to the PVD. (orig.)

  6. Interlayer utilization (including metal borides) for subsequent deposition of NSD films via microwave plasma CVD on 316 and 440C stainless steels

    Science.gov (United States)

    Ballinger, Jared

    Diamond thin films have promising applications in numerous fields due to the extreme properties of diamonds in conjunction with the surface enhancement of thin films. Biomedical applications are numerous including temporary implants and various dental and surgical instruments. The unique combination of properties offered by nanostructured diamond films that make it such an attractive surface coating include extreme hardness, low obtainable surface roughness, excellent thermal conductivity, and chemical inertness. Regrettably, numerous problems exist when attempting to coat stainless steel with diamond generating a readily delaminated film: outward diffusion of iron to the surface, inward diffusion of carbon limiting necessary surface carbon precursor, and the mismatch between the coefficients of thermal expansion yielding substantial residual stress. While some exotic methods have been attempted to overcome these hindrances, the most common approach is the use of an intermediate layer between the stainless steel substrate and the diamond thin film. In this research, both 316 stainless steel disks and 440C stainless steel ball bearings were tested with interlayers including discrete coatings and graded, diffusion-based surface enhancements. Titanium nitride and thermochemical diffusion boride interlayers were both examined for their effectiveness at allowing for the growth of continuous and adherent diamond films. Titanium nitride interlayers were deposited by cathodic arc vacuum deposition on 440C bearings. Lower temperature diamond processing resulted in improved surface coverage after cooling, but ultimately, both continuity and adhesion of the nanostructured diamond films were unacceptable. The ability to grow quality diamond films on TiN interlayers is in agreement with previous work on iron and low alloy steel substrates, and the similarly seen inadequate adhesion strength is partially a consequence of the lacking establishment of an interfacial carbide phase

  7. Phase transitions of doped carbon in CrCN coatings with modified mechanical and tribological properties via filtered cathodic vacuum arc deposition

    Energy Technology Data Exchange (ETDEWEB)

    Guan, J.J. [Faculty of Materials and Energy, Southwest University, Chongqing 400715 (China); Wang, H.Q. [College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Qin, L.Z., E-mail: qin8394@163.com [Faculty of Materials and Energy, Southwest University, Chongqing 400715 (China); Liao, B.; Liang, H. [College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Li, B. [Faculty of Materials and Energy, Southwest University, Chongqing 400715 (China)

    2017-04-15

    The CrCN coatings were fabricated onto Si (1 1 1) wafers and SUS304 stainless steel plates using filtered cathodic vacuum arc deposition (FCVAD) technique under different flow ratios of N{sub 2}/C{sub 2}H{sub 2} gas mixture. The morphology, crystalline structure and chemical composition of the coatings were characterized. It was found that the grain size reduce with increasing carbon content, which makes the CrCN coatings refined and smooth. The quasi-one-dimensional carbolite phase was also found in CrN host lattice with C{sub 2}H{sub 2} content ranging from 5% to 20%, and it will be evolved into amorphous carbon and amorphous CN{sub x} phases as C{sub 2}H{sub 2} content exceeds 20%. Moreover, we examined the mechanical and tribological properties of the CrCN coatings, and the experimental results confirmed that the friction coefficient of the coatings descend to the lowest value as 0.39 with 30% C{sub 2}H{sub 2} content, due to the graphite (sp{sup 2} C−C) phase embed in CrN host lattice; while the chromium carbon (Cr{sub 3}C{sub 2}) and diamond (sp{sup 3} C−C) phases may give rise to the increase of the coating hardness with the highest value at 23.97 GPa under 20% C{sub 2}H{sub 2} content.

  8. Chemically vapor deposited coatings for multibarrier containment of nuclear wastes

    International Nuclear Information System (INIS)

    Rusin, J.M.; Shade, J.W.; Kidd, R.W.; Browning, M.F.

    1981-01-01

    Chemical vapor deposition (CVD) was selected as a feasible method to coat ceramic cores, since the technology has previously been demonstrated for high-temperature gas-cooled reactor (HTGR) fuel particles. CVD coatings, including SiC, PyC (pyrolytic carbon), SiO 2 , and Al 2 O 3 were studied. This paper will discuss the development and characterization of PyC and Al 2 O 3 CVD coatings on supercalcine cores. Coatings were applied to 2 mm particles in either fluidized or vibrating beds. The PyC coating was deposited in a fluidized bed with ZrO 2 diluent from C 2 H 2 at temperatures between 1100 and 1200 0 C. The Al 2 O 3 coatings were deposited in a vibrated bed by a two-stage process to minimize loss of PyC during the overcoating operation. This process involved applying 10 μm of Al 2 O 3 using water vapor hydrolysis of AlCl 3 and then switching to the more surface-controlled hydrolysis via the H 2 + CO 2 reaction (3CO 2 + 3H 2 + 2AlCl 3 = Al 2 O 3 + 6HCl + 3CO). Typically, 50 to 80 μm Al 2 O 3 coatings were applied over 30 to 40 μm PyC coatings. The coatings were evaluated by metallographic examination, PyC oxidation tests, and leach resistance. After air oxidation for 100 hours at 750 0 C, the duplex PyC/Al 2 O 3 coated particles exhibited a weight loss of 0.01 percent. Leach resistance is being determined for temperatures from 50 to 150 0 C in various solutions. Typical results are given for selected ions. The leach resistance of supercalcine cores is significantly improved by the application of PyC and/or Al 2 O 3 coatings

  9. UV detectors based on epitaxial diamond films grown on single-crystal diamond substrates by vapor-phase synthesis

    International Nuclear Information System (INIS)

    Sharonov, G.V.; Petrov, S.A.; Bol'shakov, A.P.; Ral'chenko, V.G.; Kazyuchits, N.M.

    2010-01-01

    The prospects for use of CVD-technology for epitaxial growth of single-crystal diamond films of instrumental quality in UHF plasma for the production of optoelectronic devices are discussed. A technology for processing diamond single crystals that provides a perfect surface crystal structure with roughness less than 0,5 nm was developed. It was demonstrated that selective UV detectors based on synthetic single-crystal diamond substrates coated with single-crystal films can be produced. A criterion for selecting clean and structurally perfect single crystals of synthetic diamond was developed for the epitaxial growth technology. (authors)

  10. Prospects for the synthesis of large single-crystal diamonds

    International Nuclear Information System (INIS)

    Khmelnitskiy, R A

    2015-01-01

    The unique properties of diamond have stimulated the study of and search for its applications in many fields, including optics, optoelectronics, electronics, biology, and electrochemistry. Whereas chemical vapor deposition allows the growth of polycrystalline diamond plates more than 200 mm in diameter, most current diamond application technologies require large-size (25 mm and more) single-crystal diamond substrates or films suitable for the photolithography process. This is quite a challenge, because the largest diamond crystals currently available are 10 mm or less in size. This review examines three promising approaches to fabricating large-size diamond single crystals: growing large-size single crystals, the deposition of heteroepitaxial diamond films on single-crystal substrates, and the preparation of composite diamond substrates. (reviews of topical problems)

  11. Adhesion and differentiation of Saos-2 osteoblast-like cells on chromium-doped diamond-like carbon coatings.

    Science.gov (United States)

    Filova, Elena; Vandrovcova, Marta; Jelinek, Miroslav; Zemek, Josef; Houdkova, Jana; Jan Remsa; Kocourek, Tomas; Stankova, Lubica; Bacakova, Lucie

    2017-01-01

    Diamond-like carbon (DLC) thin films are promising for use in coating orthopaedic, dental and cardiovascular implants. The problem of DLC layers lies in their weak layer adhesion to metal implants. Chromium is used as a dopant for improving the adhesion of DLC films. Cr-DLC layers were prepared by a hybrid technology, using a combination of pulsed laser deposition (PLD) from a graphite target and magnetron sputtering. Depending on the deposition conditions, the concentration of Cr in the DLC layers moved from zero to 10.0 at.%. The effect of DLC layers with 0.0, 0.9, 1.8, 7.3, 7.7 and 10.0 at.% Cr content on the adhesion and osteogenic differentiation of human osteoblast-like Saos-2 cells was assessed in vitro. The DLC samples that contained 7.7 and 10.0 at.% of Cr supported cell spreading on day 1 after seeding. On day three after seeding, the most apparent vinculin-containing focal adhesion plaques were also found on samples with higher concentrations of chromium. On the other hand, the expression of type I collagen and alkaline phosphatase at the mRNA and protein level was the highest on Cr-DLC samples with a lower concentration of Cr (0-1.8 at.%). We can conclude that higher concentrations of chromium supported cell adhesion; however DLC and DLC doped with a lower concentration of chromium supported osteogenic cell differentiation.

  12. Thermal diffusivity of diamond films using a laser pulse technique

    International Nuclear Information System (INIS)

    Albin, S.; Winfree, W.P.; Crews, B.S.

    1990-01-01

    Polycrystalline diamond films were deposited using a microwave plasma-enhanced chemical vapor deposition process. A laser pulse technique was developed to measure the thermal diffusivity of diamond films deposited on a silicon substrate. The effective thermal diffusivity of a diamond film on silicon was measured by observing the phase and amplitude of the cyclic thermal waves generated by laser pulses. An analytical model is presented to calculate the effective inplane (face-parallel) diffusivity of a two-layer system. The model is used to reduce the effective thermal diffusivity of the diamond/silicon sample to a value for the thermal diffusivity and conductivity of the diamond film

  13. Thin diamond films for tribological applications

    International Nuclear Information System (INIS)

    Wong, M.S.; Meilunas, R.; Ong, T.P.; Chang, R.P.H.

    1989-01-01

    Diamond films have been deposited on Si, Mo and many other substrates by microwave and radio frequency plasma enhanced chemical vapor deposition. Although the adhesion between the diamond film and most of the metal substrates is poor due to residual thermal stress from the mismatch of thermal expansion coefficients, the authors have developed processes to promote the growth of uniform and continuous diamond films with enhanced adhesion to metal substrates for tribological applications. The tribological properties of these films are measured using a ring-on-block tribotester. The coefficients of friction of diamond films sliding against a 52100 steel ring under the same experimental conditions are found to be significantly different depending on the morphology, grain size and roughness of the diamond films. However, under all cases tested, it is found that for uniform and continuous diamond films with small grain size of 1-3 micrometers, the coefficient of friction of the diamond film sliding against a steel ring under lubrication of a jet of mineral oil is about 0.04

  14. Performance characterization of Ni60-WC coating on steel processed with supersonic laser deposition

    Directory of Open Access Journals (Sweden)

    Fang Luo

    2015-03-01

    Full Text Available Ni60-WC particles are used to improve the wear resistance of hard-facing steel due to their high hardness. An emerging technology that combines laser with cold spraying to deposit the hard-facing coatings is known as supersonic laser deposition. In this study, Ni60-WC is deposited on low-carbon steel using SLD. The microstructure and performance of the coatings are investigated through SEM, optical microscopy, EDS, XRD, microhardness and pin-on-disc wear tests. The experimental results of the coating processed with the optimal parameters are compared to those of the coating deposited using laser cladding.

  15. The Influence of the Coating Deposition Process on the Interdiffusion Behavior Between Nickel-Based Superalloys and MCrAlY Bond Coats

    Science.gov (United States)

    Elsaß, M.; Frommherz, M.; Oechsner, M.

    2018-02-01

    In this work, interdiffusion between two nickel-based superalloys and two MCrAlY bond coats is investigated. The MCrAlY bond coats were applied using two different spraying processes, high velocity oxygen fuel spraying (HVOF) and low-pressure plasma spraying. Of primary interest is the evolution of Kirkendall porosity, which can form at the interface between substrate and bond coat and depends largely on the chemical compositions of the coating and substrate. Experimental evidence further suggested that the formation of Kirkendall porosity depends on the coating deposition process. Formation of porosity at the interface causes a degradation of the bonding strength between substrate and coating. After coating deposition, the samples were annealed at 1050 °C for up to 2000 h. Microstructural and compositional analyses were performed to determine and evaluate the Kirkendall porosity. The results reveal a strong influence of both the coating deposition process and the chemical compositions. The amount of Kirkendall porosity formed, as well as the location of appearance, is largely influenced by the coating deposition process. In general, samples with bond coats applied by means of HVOF show accelerated element diffusion. It is hypothesized that recrystallization of the substrate material is a main root cause for these observations.

  16. Perfect alignment and preferential orientation of nitrogen-vacancy centers during chemical vapor deposition diamond growth on (111) surfaces

    International Nuclear Information System (INIS)

    Michl, Julia; Zaiser, Sebastian; Jakobi, Ingmar; Waldherr, Gerald; Dolde, Florian; Neumann, Philipp; Wrachtrup, Jörg; Teraji, Tokuyuki; Doherty, Marcus W.; Manson, Neil B.; Isoya, Junichi

    2014-01-01

    Synthetic diamond production is a key to the development of quantum metrology and quantum information applications of diamond. The major quantum sensor and qubit candidate in diamond is the nitrogen-vacancy (NV) color center. This lattice defect comes in four different crystallographic orientations leading to an intrinsic inhomogeneity among NV centers, which is undesirable in some applications. Here, we report a microwave plasma-assisted chemical vapor deposition diamond growth technique on (111)-oriented substrates, which yields perfect alignment (94% ± 2%) of as-grown NV centers along a single crystallographic direction. In addition, clear evidence is found that the majority (74% ± 4%) of the aligned NV centers were formed by the nitrogen being first included in the (111) growth surface and then followed by the formation of a neighboring vacancy on top. The achieved homogeneity of the grown NV centers will tremendously benefit quantum information and metrology applications

  17. Titanium dioxide antireflection coating for silicon solar cells by spray deposition

    Science.gov (United States)

    Kern, W.; Tracy, E.

    1980-01-01

    A high-speed production process is described for depositing a single-layer, quarter-wavelength thick antireflection coating of titanium dioxide on metal-patterned single-crystal silicon solar cells for terrestrial applications. Controlled atomization spraying of an organotitanium solution was selected as the most cost-effective method of film deposition using commercial automated equipment. The optimal composition consists of titanium isopropoxide as the titanium source, n-butyl acetate as the diluent solvent, sec-butanol as the leveling agent, and 2-ethyl-1-hexanol to render the material uniformly depositable. Application of the process to the coating of circular, large-diameter solar cells with either screen-printed silver metallization or with vacuum-evaporated Ti/Pd/Ag metallization showed increases of over 40% in the electrical conversion efficiency. Optical characteristics, corrosion resistance, and several other important properties of the spray-deposited film are reported. Experimental evidence indicates a wide tolerance in the coating thickness upon the overall efficiency of the cell. Considerations pertaining to the optimization of AR coatings in general are discussed, and a comprehensive critical survey of the literature is presented.

  18. Friction Properties of Polished Cvd Diamond Films Sliding against Different Metals

    Science.gov (United States)

    Lin, Zichao; Sun, Fanghong; Shen, Bin

    2016-11-01

    Owing to their excellent mechanical and tribological properties, like the well-known extreme hardness, low coefficient of friction and high chemical inertness, chemical vapor deposition (CVD) diamond films have found applications as a hard coating for drawing dies. The surface roughness of the diamond films is one of the most important attributes to the drawing dies. In this paper, the effects of different surface roughnesses on the friction properties of diamond films have been experimentally studied. Diamond films were fabricated using hot filament CVD. The WC-Co (Co 6wt.%) drawing dies were used as substrates. A gas mixture of acetone and hydrogen gas was used as the feedstock gas. The CVD diamond films were polished using mechanical polishing. Polished diamond films with three different surface roughnesses, as well as the unpolished diamond film, were fabricated in order to study the tribological performance between the CVD diamond films and different metals with oil lubrication. The unpolished and polished CVD diamond films are characterized with scanning electron microscope (SEM), atomic force microscope (AFM), surface profilometer, Raman spectrum and X-ray diffraction (XRD). The friction examinations were carried out by using a ball-on-plate type reciprocating friction tester. Low carbide steel, stainless steel, copper and aluminum materials were used as counterpart balls. Based on this study, the results presented the friction coefficients between the polished CVD films and different metals. The friction tests demonstrate that the smooth surface finish of CVD diamond films is beneficial for reducing their friction coefficients. The diamond films exhibit low friction coefficients when slid against the stainless steel balls and low carbide steel ball, lower than that slid against copper ball and aluminum ball, attributed to the higher ductility of copper and aluminum causing larger amount of wear debris adhering to the sliding interface and higher adhesive

  19. Trapezoidal diffraction grating beam splitters in single crystal diamond

    Science.gov (United States)

    Kiss, Marcell; Graziosi, Teodoro; Quack, Niels

    2018-02-01

    Single Crystal Diamond has been recognized as a prime material for optical components in high power applications due to low absorption and high thermal conductivity. However, diamond microstructuring remains challenging. Here, we report on the fabrication and characterization of optical diffraction gratings exhibiting a symmetric trapezoidal profile etched into a single crystal diamond substrate. The optimized grating geometry diffracts the transmitted optical power into precisely defined proportions, performing as an effective beam splitter. We fabricate our gratings in commercially available single crystal CVD diamond plates (2.6mm x 2.6mm x 0.3mm). Using a sputter deposited hard mask and patterning by contact lithography, the diamond is etched in an inductively coupled oxygen plasma with zero platen power. The etch process effectively reveals the characteristic {111} diamond crystal planes, creating a precisely defined angled (54.7°) profile. SEM and AFM measurements of the fabricated gratings evidence the trapezoidal shape with a pitch of 3.82μm, depth of 170 nm and duty cycle of 35.5%. Optical characterization is performed in transmission using a 650nm laser source perpendicular to the sample. The recorded transmitted optical power as function of detector rotation angle shows a distribution of 21.1% in the 0th order and 23.6% in each +/-1st order (16.1% reflected, 16.6% in higher orders). To our knowledge, this is the first demonstration of diffraction gratings with trapezoidal profile in single crystal diamond. The fabrication process will enable beam splitter gratings of custom defined optical power distribution profiles, while antireflection coatings can increase the efficiency.

  20. Optimization and characterization of adhesion properties of DLC coatings on different substrates

    International Nuclear Information System (INIS)

    Waseem, B; Alam, S; Irfan, M; Shahid, M; Soomro, B D; Hashim, S; Iqbal, R

    2014-01-01

    The Diamond Like Carbon coatings (DLC) are gaining prime importance in the field of surface engineering especially cutting tools technology. The self lubricating property of these coatings makes them unique among other coatings like TiN, TiAlN, CrN etc. Unlike other coatings, DLC coatings give better surface finish and their self lubrication reduces the wear of a part to large extent. In present work, different substrates were selected to study the wear and adhesion behavior of DLC coatings. The coating was produced by physical Vapor Deposition (PVD) technique and the adhesive properties of DLC coatings were analyzed under ambient conditions using nano Scratch testing. Scanning electron microscope (SEM) was used to observe the scratches and their mechanisms

  1. Optimization and characterization of adhesion properties of DLC coatings on different substrates

    International Nuclear Information System (INIS)

    Waseem, B.; Alam, S.; Irfan, M.; Shahid, M.; Soomro, B. D.; Hashim, S.; Iqbal, R.

    2013-01-01

    The Diamond Like Carbon coatings (DLC) are gaining prime importance in the field of surface engineering especially cutting tools technology. The self lubricating property of these coatings makes them unique among other coatings like TiN, TiAlN, CrN etc. Unlike other coatings, DLC coatings give better surface finish and their self lubrication reduces the wear of a part to large extent. In present work, different substrates were selected to study the wear and adhesion behavior of DLC coatings. The coating was produced by physical Vapor Deposition (PVD) technique and the adhesive properties of DLC coatings were analyzed under ambient conditions using nano Scratch testing. Scanning electron microscope (SEM) was used to observe the scratches and their mechanisms. (author)

  2. Electrodeposition of diamond-like carbon films on titanium alloy using organic liquids: Corrosion and wear resistance

    International Nuclear Information System (INIS)

    Falcade, Tiago; Shmitzhaus, Tobias Eduardo; Gomes dos Reis, Otávio; Vargas, André Luis Marin; Hübler, Roberto; Müller, Iduvirges Lourdes; Fraga Malfatti, Célia de

    2012-01-01

    Highlights: ► The electrodeposition may be conducted at room temperature. ► The DLC films have good resistance to corrosion in saline environments. ► The films have lower coefficient of friction than the uncoated substrate. ► The abrasive wear protection is evident in coated systems. - Abstract: Diamond-like carbon (DLC) films have been studied as coatings for corrosion protection and wear resistance because they have excellent chemical inertness in traditional corrosive environments, besides presenting a significant reduction in coefficient of friction. Diamond-like carbon (DLC) films obtained by electrochemical deposition techniques have attracted a lot of interest, regarding their potential in relation to the vapor phase deposition techniques. The electrochemical deposition techniques are carried out at room temperature and do not need vacuum system, making easier this way the technological transfer. At high electric fields, the organic molecules polarize and react on the electrode surface, forming carbon films. The aim of this work was to obtain DLC films onto Ti6Al4V substrate using as electrolyte: acetonitrile (ACN) and N,N-dimethylformamide (DMF). The films were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM), Raman spectroscopy, potentiodynamic polarization and wear tests. The results show that these films can improve, significantly, the corrosion resistance of titanium and its alloys and their wear resistance.

  3. High-speed deposition of titanium carbide coatings by laser-assisted metal–organic CVD

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Yansheng [Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074 (China); Tu, Rong, E-mail: turong@whut.edu.cn [State Key Laboratory of Advanced Technology for Material Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Goto, Takashi [Institute for Materials Research, Tohoku University, Aoba-ku, 2-1-1 Katahira, Sendai 980-8577 (Japan)

    2013-08-01

    Graphical abstract: - Highlights: • A semiconductor laser was first used to prepare wide-area LCVD-TiC{sub x} coatings. • The effect of laser power for the deposition of TiC{sub x} coatings was discussed. • TiC{sub x} coatings showed a columnar cross section and a dense surface texture. • TiC{sub x} coatings had a 1–4 order lower laser density than those of previous reports. • This study gives the possibility of LCVD applying on the preparation of TiC{sub x} coating. - Abstract: A semiconductor laser-assisted chemical vapor deposition (LCVD) of titanium carbide (TiC{sub x}) coatings on Al{sub 2}O{sub 3} substrate using tetrakis (diethylamido) titanium (TDEAT) and C{sub 2}H{sub 2} as source materials were investigated. The influences of laser power (P{sub L}) and pre-heating temperature (T{sub pre}) on the microstructure and deposition rate of TiC{sub x} coatings were examined. Single phase of TiC{sub x} coatings were obtained at P{sub L} = 100–200 W. TiC{sub x} coatings had a cauliflower-like surface and columnar cross section. TiC{sub x} coatings in the present study had the highest R{sub dep} (54 μm/h) at a relative low T{sub dep} than those of conventional CVD-TiC{sub x} coatings. The highest volume deposition rate (V{sub dep}) of TiC{sub x} coatings was about 4.7 × 10{sup −12} m{sup 3} s{sup −1}, which had 3–10{sup 5} times larger deposition area and 1–4 order lower laser density than those of previous LCVD using CO{sub 2}, Nd:YAG and argon ion laser.

  4. Plasmon-organic fiber interactions in diamond-like carbon coated nanostructured gold films

    Science.gov (United States)

    Cielecki, Paweł Piotr; Sobolewska, Elżbieta Karolina; Kostiuočenko, Oksana; Leißner, Till; Tamulevičius, Tomas; Tamulevičius, Sigitas; Rubahn, Horst-Günter; Adam, Jost; Fiutowski, Jacek

    2017-11-01

    Gold is the most commonly used plasmonic material, however soft and prone to mechanical deformations. It has been shown that the durability of gold plasmonic substrates can be improved by applying a protective diamond-like carbon (DLC) coating. In this work, we investigate the influence of such protective layers on plasmonic interactions in organic-plasmonic hybrid systems. We consider systems, consisting of 1-Cyano-quaterphenylene nanofibers on top of gold nano-square plasmonic arrays, coated with protective layers of varying thickness. We numerically investigate the spectral position of surface plasmon polariton resonances and electric field intensity, as a function of protective layer thickness, using the finite-difference time-domain method. To confirm the numerically indicated field enhancement preservation on top of protective layers, we experimentally map the second harmonic response of organic nanofibers. Subsequently, we characterize the plasmonic coupling between organic nanofibers and underlying substrates, considered as one of the main loss channels for photoluminescence from nanofibers, by time-resolved photoluminescence spectroscopy. Our findings reveal that, for the investigated system, plasmonic interactions are preserved for DLC coatings up to 55 nm. This is relevant for the fabrication of new passive and active plasmonic components with increased durability and hence prolonged lifetime.

  5. Microstructural development in physical vapour-deposited partially stabilized zirconia thermal barrier coatings

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Y. H. (Center for Intelligent Processing of Materials, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609-2280 (United States)); Biederman, R.R. (Center for Intelligent Processing of Materials, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609-2280 (United States)); Sisson, R.D. Jr. (Center for Intelligent Processing of Materials, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609-2280 (United States))

    1994-10-01

    The effects of processing parameters of physical vapour deposition on the microstructure of partially stabilized zirconia (PSZ) thermal barrier coatings have been experimentally investigated. Emphasis has been placed on the crystallographic texture of the PSZ coatings and the microstructure of the top surface of the PSZ coatings as well as the metal-ceramic interface. The variations in the deposition chamber temperature, substrate thickness, substrate rotation and vapour incidence angle resulted in the observation of significant differences in the crystallographic texture and microstructure of the PSZ coatings. ((orig.))

  6. Fluidized bed deposition and evaluation of silicon carbide coatings on microspheres

    International Nuclear Information System (INIS)

    Federer, J.I.

    1977-01-01

    The fuel element for the HTGR is an array of closely packed fuel microspheres in a carbonaceous matrix. A coating of dense silicon carbide (SiC), along with pyrocarbon layers, is deposited on the fueled microspheres to serve as a barrier against diffusion of fission products. The microspheres are coated with silicon carbide in a fluidized bed by reaction of methyltrichlorosilane (CH 3 SiCl 3 or MTS) and hydrogen at elevated temperatures. The principal variables of coating temperature and reactant gas composition (H 2 /MTS ratio) have been correlated with coating rate, morphology, stoichiometry, microstructure, and density. The optimum temperature for depositing highly dense coatings is in the range 1475 to 1675 0 C. Lower temperatures result in silicon-rich deposits, while higher temperatures may cause unacceptable porosity. The optimum H 2 /MTS ratio for highly dense coatings is 20 or more (approximately 5% MTS or less). The amount of grown-in porosity increases as the H 2 /MTS ratio decreases below 20. The requirement that the H 2 /MTS ratio be about 20 or more imposes a practical restraint on coating rate, since increasing the total flow rate would eventually expel microspheres from the coating tube. Evaluation of stoichiometry, morphology, and microstructure support the above mentioned optimum conditions of temperature and reactant gas composition. 18 figures, 3 tables

  7. STRUCTURING OF DIAMOND FILMS USING MICROSPHERE LITHOGRAPHY

    Directory of Open Access Journals (Sweden)

    Mária Domonkos

    2014-10-01

    Full Text Available In this study, the structuring of micro- and nanocrystalline diamond thin films is demonstrated. The structuring of the diamond films is performed using the technique of microsphere lithography followed by reactive ion etching. Specifically, this paper presents a four-step fabrication process: diamond deposition (microwave plasma assisted chemical vapor deposition, mask preparation (by the standard Langmuir-Blodgett method, mask modification and diamond etching. A self-assembled monolayer of monodisperse polystyrene (PS microspheres with close-packed ordering is used as the primary template. Then the PS microspheres and the diamond films are processed in capacitively coupled radiofrequency plasma  using different plasma chemistries. This fabrication method illustrates the preparation of large arrays of periodic and homogeneous hillock-like structures. The surface morphology of processed diamond films is characterized by scanning electron microscopy and atomic force microscope. The potential applications of such diamond structures in various fields of nanotechnology are also briefly discussed.

  8. Anti-sticking behavior of DLC-coated silicon micro-molds

    International Nuclear Information System (INIS)

    Saha, B; Tor, S B; Liu, E; Khun, N W; Hardt, D E; Chun, J H

    2009-01-01

    Pure carbon- (C), nitrogen- (N) and titanium- (Ti) doped diamond-like carbon (DLC) coatings were deposited on silicon (Si) micro-molds by dc magnetron sputtering deposition to improve the tribological performance of the micro-molds. The coated and uncoated Si molds were used in injection molding for the fabrication of secondary metal-molds, which were used for the replication of micro-fluidic devices. The bonding structure, surface roughness, surface energy, critical load and friction coefficient of the DLC coatings were characterized with micro-Raman spectroscopy, atomic force microscopy (AFM), contact angle, microscratch and ball-on-disc sliding wear tests, respectively. It was observed that the doping conditions had significant effects on Raman peak positions, mechanical and tribological properties of the coatings. The G peak shifted toward a lower position with N and Ti doping. The DLC coating deposited with 1 sccm N 2 flow rate showed the lowest G peak position and the smoothest surface. The surface energies of the pure carbon and Ti-doped DLC coatings were lower than that of the N-doped DLC, which was more significant at a higher N 2 flow rate. In terms of adhesion and friction coefficient, it was observed that the Ti-doped DLC coating had the best performance. Ti incorporated in the DLC coating decreased the residual stress of the coating, which improved the adhesive strength of the coating with the Si substrate

  9. Operation of microstrip gas chambers manufactured on glass coated with high resistivity diamond-like layers

    CERN Document Server

    Boimska, B; Dominik, Wojciech; Hoch, M; Million, Gilbert; Ropelewski, Leszek; Sauli, Fabio; Sharma, A

    1997-01-01

    We describe recent observations and measurements realized with micro-strip gas chambers (MSGCs) manufactured on boro-silicate glass coated with a thin layer of diamond-like carbon (DLC) having a surface resistivity around 4.10$^{16}\\Omega/\\Box$. The role of the back-pla electrode configuration and potential in the detector performance has been studied. Even for this very high resistivity of the coatings, MSGCs operate differently from those manufactured on bare boro-silicate glass; the charge gain increases with the radiation flux for counting rates above 103 Hz/mm2, reaching a value 60% higher for 105 Hz/mm2. This behavior does not depend on the presence and potential of the back plane electrode; however, both maximum gain and rate capability are influenced by the drift field. From this study, compared with measurements realized previously with other detectors, we deduce that for stable high rate operation of MSGCs the resistivity of the coating should not exceed ~10$^{15}\\Omega/\\Box$.

  10. Improved dental implant drill durability and performance using heat and wear resistant protective coatings.

    Science.gov (United States)

    Er, Nilay; Alkan, Alper; İlday, Serim; Bengu, Erman

    2018-03-02

    Dental implant drilling procedure is an essential step for implant surgery and frictional heat appeared in bone during drilling is a key factor affecting the success of an implant. The aim of this study is to increase the dental implant drill lifetime and performance using heat- and wear-resistant protective coatings hence to decrease the alveolar bone temperature caused by the dental implant drilling procedure. Commercially obtained stainless steel drills were coated with titanium aluminum nitride, diamond-like carbon, titanium boron nitride, and boron nitride coatings via magnetron-sputter deposition. Drilling procedure was performed on a bovine femoral cortical bone under the conditions mimicking clinical practice, where the tests were performed both under water-assisted cooling and under the conditions without any cooling was applied. Coated drill performances and durabilities were compared to that of three commonly used commercial drills which surfaces are made from namely; zirconia, black diamond and stainless steel. Protective coatings with boron nitride, titanium boron nitride and diamond-like carbon have significantly improved drill performance and durability. Especially boron nitride-coated drills have performed within safe bone temperature limits for 50 drillings even without any cooling is applied. Titanium aluminium nitride coated drills did not show any improvement over commercially obtained stainless steel drills. Surface modification using heat and wear resistant coatings is an easy and highly effective way to improve implant drill performance and durability, which can reflect positively on surgical procedure and healing period afterwards. The noteworthy success of different types of coatings is novel and likely to be applicable to various other medical systems.

  11. A Comparative Study of Three Different Chemical Vapor Deposition Techniques of Carbon Nanotube Growth on Diamond Films

    Directory of Open Access Journals (Sweden)

    Betty T. Quinton

    2013-01-01

    Full Text Available This paper compares between the methods of growing carbon nanotubes (CNTs on diamond substrates and evaluates the quality of the CNTs and the interfacial strength. One potential application for these materials is a heat sink/spreader for high-power electronic devices. The CNTs and diamond substrates have a significantly higher specific thermal conductivity than traditional heat sink/spreader materials making them good replacement candidates. Only limited research has been performed on these CNT/diamond structures and their suitability of different growth methods. This study investigates three potential chemical vapor deposition (CVD techniques for growing CNTs on diamond: thermal CVD (T-CVD, microwave plasma-enhanced CVD (MPE-CVD, and floating catalyst thermal CVD (FCT-CVD. Scanning electron microscopy (SEM and high-resolution transmission electron microscopy (TEM were used to analyze the morphology and topology of the CNTs. Raman spectroscopy was used to assess the quality of the CNTs by determining the ID/IG peak intensity ratios. Additionally, the CNT/diamond samples were sonicated for qualitative comparisons of the durability of the CNT forests. T-CVD provided the largest diameter tubes, with catalysts residing mainly at the CNT/diamond interface. The MPE-CVD process yielded non uniform defective CNTs, and FCT-CVD resulted in the smallest diameter CNTs with catalyst particles imbedded throughout the length of the nanotubes.

  12. Analyses of Biofilm on Implant Abutment Surfaces Coating with Diamond-Like Carbon and Biocompatibility.

    Science.gov (United States)

    Huacho, Patricia Milagros Maquera; Nogueira, Marianne N Marques; Basso, Fernanda G; Jafelicci Junior, Miguel; Francisconi, Renata S; Spolidorio, Denise M P

    2017-01-01

    The aim of this study was to evaluate the surface free energy (SFE), wetting and surface properties as well as antimicrobial, adhesion and biocompatibility properties of diamond-like carbon (DLC)-coated surfaces. In addition, the leakage of Escherichia coli through the abutment-dental implant interface was also calculated. SFE was calculated from contact angle values; R a was measured before and after DLC coating. Antimicrobial and adhesion properties against E. coli and cytotoxicity of DLC with human keratinocytes (HaCaT) were evaluated. Further, the ability of DLC-coated surfaces to prevent the migration of E. coli into the external hexagonal implant interface was also evaluated. A sterile technique was used for the semi-quantitative polymerase chain reaction (semi-quantitative PCR). The surfaces showed slight decreases in cell viability (p0.05). It was concluded that DLC was shown to be a biocompatible material with mild cytotoxicity that did not show changes in R a, SFE, bacterial adhesion or antimicrobial properties and did not inhibit the infiltration of E. coli into the abutment-dental implant interface.

  13. Development of coatings for ultrasonic additive manufacturing sonotrode using laser direct metal deposition process

    Energy Technology Data Exchange (ETDEWEB)

    Niyanth S, Niyanth [ORNL; Dehoff, Ryan R [ORNL; Jordan, Brian H [ORNL; Babu, Sudarsanam Suresh [ORNL

    2016-10-01

    ORNL partnered with Fabrisonic, LLC to develop galling resistant hard facing coatings on sonotrodes used to fabricate 3D printed materials using ultrasonic additive manufacturing. The development and deployment of a coated sonotrode is expected to push the existing state of the art to facilitate the solidstate additive manufacturing of hard steels and titanium alloys. To this effect a structurally amorphous stainless steel material and cobalt chrome material were deposited on the sonotrode material. Both the deposits showed good adhesion to the substrate. The coatings made using the structurally amorphous steel materials showed cracking during the initial trials and cracking was eliminated by deposition on a preheated substrate. Both the coatings show hardness in excess of 600 HVN. Thus the phase 1 of this project has been used to identify suitable materials to use to coat the sonotrode. Despite the fact that successful deposits were obtained, the coatings need to be evaluated by performing detailed galling tests at various temperatures. In addition field tests are also necessary to test the stability of these coatings in a high cycle ultrasonic vibration mode. If awarded, phase 2 of the project would be used to optimize the composition of the deposit material to maximize galling resistance. The industrial partner would then use the coated sonotrode to fabricate builds made of austenitic stainless steel to test the viability of using a coated sonotrode.

  14. Diamond film growth with modification properties of adhesion between substrate and diamond film

    Directory of Open Access Journals (Sweden)

    Setasuwon P.

    2004-03-01

    Full Text Available Diamond film growth was studied using chemical vapor deposition (CVD. A special equipment was build in-house, employing a welding torch, and substrate holder with a water-cooling system. Acetylene and oxygen were used as combustion gases and the substrate was tungsten carbide cobalt. It was found that surface treatments, such as diamond powder scratching or acid etching, increase the adhesion and prevent the film peel-off. Diamond powder scratching and combined diamond powder scratching with acid etching gave the similar diamond film structure with small grain and slightly rough surface. The diamond film obtained with both treatments has high adhesion and can withstand internal stress better than ones obtained by untreated surface or acid etching alone. It was also found that higher substrate temperature produced smoother surface and more uniform diamond grain.

  15. Electroless deposition of nickel-boron coatings using low frequency ultrasonic agitation: Effect of ultrasonic frequency on the coatings.

    Science.gov (United States)

    Bonin, L; Bains, N; Vitry, V; Cobley, A J

    2017-05-01

    The effect of ultrasound on the properties of Nickel-Boron (NiB) coatings was investigated. NiB coatings were fabricated by electroless deposition using either ultrasonic or mechanical agitation. The deposition of Ni occurred in an aqueous bath containing a reducible metal salt (nickel chloride), reducing agent (sodium borohydride), complexing agent (ethylenediamine) and stabilizer (lead tungstate). Due to the instability of the borohydride in acidic, neutral and slightly alkaline media, pH was controlled at pH 12±1 in order to avoid destabilizing the bath. Deposition was performed in three different configurations: one with a classical mechanical agitation at 300rpm and the other two employing ultrasound at a frequency of either 20 or 35kHz. The microstructures of the electroless coatings were characterized by a combination of optical Microscopy and Scanning Electron Microscope (SEM). The chemistry of the coatings was determined by ICP-AES (Inductively Coupled Plasma - Atomic Emission Spectrometry) after dissolution in aqua regia. The mechanical properties of the coatings were established by a combination of roughness measurements, Vickers microhardness and pin-on-disk tribology tests. Lastly, the corrosion properties were analysed by potentiodynamic polarization. The results showed that low frequency ultrasonic agitation could be used to produce coatings from an alkaline NiB bath and that the thickness of coatings obtained could be increased by over 50% compared to those produced using mechanical agitation. Although ultrasonic agitation produced a smoother coating and some alteration of the deposit morphology was observed, the mechanical and corrosion properties were very similar to those found when using mechanical agitation. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Plasma deposition of antimicrobial coating on organic polymer

    Science.gov (United States)

    Rżanek-Boroch, Zenobia; Dziadczyk, Paulina; Czajkowska, Danuta; Krawczyk, Krzysztof; Fabianowski, Wojciech

    2013-02-01

    Organic materials used for packing food products prevent the access of microorganisms or gases, like oxygen or water vapor. To prolong the stability of products, preservatives such as sulfur dioxide, sulfites, benzoates, nitrites and many other chemical compounds are used. To eliminate or limit the amount of preservatives added to food, so-called active packaging is sought for, which would limit the development of microorganisms. Such packaging can be achieved, among others, by plasma modification of a material to deposit on its surface substances inhibiting the growth of bacteria. In this work plasma modification was carried out in barrier discharge under atmospheric pressure. Sulfur dioxide or/and sodium oxide were used as the coating precursors. As a result of bacteriological studies it was found that sulfur containing coatings show a 16% inhibition of Salmonella bacteria growth and 8% inhibition of Staphylococcus aureus bacteria growth. Sodium containing coatings show worse (by 10%) inhibiting properties. Moreover, films with plasma deposited coatings show good sealing properties against water vapor. Contribution to the Topical Issue "13th International Symposium on High Pressure Low Temperature Plasma Chemistry (Hakone XIII)", Edited by Nicolas Gherardi, Henryca Danuta Stryczewska and Yvan Ségui.

  17. Deposition and characterization of sputtered hexaboride coatings

    International Nuclear Information System (INIS)

    Waldhauser, W.

    1996-06-01

    Hexaborides of the rare-earth elements ReB 6 are potential materials for cathode applications since they combine properties such as low work function, good electrical conductivity, high melting point as well as low volatility at high temperatures. Due to their high hardness and colorations ranging from blue to purple these compounds are also considered for applications to coatings for decoration of consumer products. At present, either rods of sintered LaB 6 or single LaB 6 crystals are indirectly heated to induce emission. In this workboride coatings were deposited onto various substrates employing non-reactive magnetron sputtering from LaB 6 , CeB 6 , SmB 6 and YB 6 targets. Coatings deposited were examined using scanning electron microscopy, X-ray diffraction, electron probe microanalysis. Vickers microhardness, colorimeter and spectroscopic ellipsometry measurements. Electron emission characteristics of the coatings were studied by the thermionic emission and the contact potential method. After optimization of the sputtering parameters fine-columnar or partially amorphous films with atomic ratios of boron to metal in the order of 5 to 7.5 were obtained. The tendency to form the corresponding hexaboride phase decreases from LaB 6 , CeB 6 and SmB 6 to YB 6 . The work function was measured to be in the range of 2.6 to 3.3 eV. Vickers microhardness values lie between 1500 and 2000 HVO.01. LaB 6 coatings showed the most pronounced visual color impression corresponding to dark violet. The results obtained indicate that sputtered hexaboride films are well suited for decorative and thermionic applications. (author)

  18. Oxygen plasma etching of silver-incorporated diamond-like carbon films

    International Nuclear Information System (INIS)

    Marciano, F.R.; Bonetti, L.F.; Pessoa, R.S.; Massi, M.; Santos, L.V.; Trava-Airoldi, V.J.

    2009-01-01

    Diamond-like carbon (DLC) film as a solid lubricant coating represents an important area of investigation related to space devices. The environment for such devices involves high vacuum and high concentration of atomic oxygen. The purpose of this paper is to study the behavior of silver-incorporated DLC thin films against oxygen plasma etching. Silver nanoparticles were produced through an electrochemical process and incorporated into DLC bulk during the deposition process using plasma enhanced chemical vapor deposition technique. The presence of silver does not affect significantly DLC quality and reduces by more than 50% the oxygen plasma etching. Our results demonstrated that silver nanoparticles protect DLC films against etching process, which may increase their lifetime in low earth orbit environment.

  19. Oxygen plasma etching of silver-incorporated diamond-like carbon films

    Energy Technology Data Exchange (ETDEWEB)

    Marciano, F.R., E-mail: fernanda@las.inpe.b [Instituto Nacional de Pesquisas Espaciais (INPE), Laboratorio Associado de Sensores e Materiais (LAS), Av. dos Astronautas 1758, Sao Jose dos Campos, 12227-010, SP (Brazil); Instituto Tecnologico de Aeronautica (ITA), Centro Tecnico Aeroespacial (CTA), Pca. Marechal Eduardo Gomes, 50-Sao Jose dos Campos, 12228-900, SP (Brazil); Bonetti, L.F. [Clorovale Diamantes Industria e Comercio Ltda, Estr. do Torrao de Ouro, 500-Sao Jose dos Campos, 12229-390, SP (Brazil); Pessoa, R.S.; Massi, M. [Instituto Tecnologico de Aeronautica (ITA), Centro Tecnico Aeroespacial (CTA), Pca. Marechal Eduardo Gomes, 50-Sao Jose dos Campos, 12228-900, SP (Brazil); Santos, L.V.; Trava-Airoldi, V.J. [Instituto Nacional de Pesquisas Espaciais (INPE), Laboratorio Associado de Sensores e Materiais (LAS), Av. dos Astronautas 1758, Sao Jose dos Campos, 12227-010, SP (Brazil)

    2009-08-03

    Diamond-like carbon (DLC) film as a solid lubricant coating represents an important area of investigation related to space devices. The environment for such devices involves high vacuum and high concentration of atomic oxygen. The purpose of this paper is to study the behavior of silver-incorporated DLC thin films against oxygen plasma etching. Silver nanoparticles were produced through an electrochemical process and incorporated into DLC bulk during the deposition process using plasma enhanced chemical vapor deposition technique. The presence of silver does not affect significantly DLC quality and reduces by more than 50% the oxygen plasma etching. Our results demonstrated that silver nanoparticles protect DLC films against etching process, which may increase their lifetime in low earth orbit environment.

  20. Physically vapor deposited coatings on tools: performance and wear phenomena

    International Nuclear Information System (INIS)

    Koenig, W.; Fritsch, R.; Kammermeier, D.

    1991-01-01

    Coatings produced by physical vapor deposition (PVD) enhance the performance of tools for a broad variety of production processes. In addition to TiN, nowadays (Ti,Al)N and Ti(C,N) coated tools are available. This gives the opportunity to compare the performance of different coatings under identical machining conditions and to evaluate causes and phenomena of wear. TiN, (Ti,Al)N and Ti(C,N) coatings on high speed steel (HSS) show different performances in milling and turning of heat treated steel. The thermal and frictional properties of the coating materials affect the structure, the thickness and the flow of the chips, the contact area on the rake face and the tool life. Model tests show the influence of internal cooling and the thermal conductivity of coated HSS inserts. TiN and (Ti,Zr)N PVD coatings on cemented carbides were examined in interrupted turning and in milling of heat treated steel. Experimental results show a significant influence of typical time-temperature cycles of PVD and chemical vapor deposition (CVD) coating processes on the physical data and on the performance of the substrates. PVD coatings increase tool life, especially towards lower cutting speeds into ranges which cannot be applied with CVD coatings. The reason for this is the superior toughness of the PVD coated carbide. The combination of tough, micrograin carbide and PVD coating even enables broaching of case hardened sliding gears at a cutting speed of 66 m min -1 . (orig.)

  1. Preparation of rutile TiO(2) coating by thermal chemical vapor deposition for anticoking applications.

    Science.gov (United States)

    Tang, Shiyun; Wang, Jianli; Zhu, Quan; Chen, Yaoqiang; Li, Xiangyuan

    2014-10-08

    To inhibit the metal catalytic coking and improve the oxidation resistance of TiN coating, rutile TiO2 coating has been directly designed as an efficient anticoking coating for n-hexane pyrolysis. TiO2 coatings were prepared on the inner surface of SS304 tubes by a thermal CVD method under varied temperatures from 650 to 900 °C. The rutile TiO2 coating was obtained by annealing the as-deposited TiO2 coating, which is an alternative route for the deposition of rutile TiO2 coating. The morphology, elemental and phase composition of TiO2 coatings were characterized by SEM, EDX and XRD, respectively. The results show that deposition temperature of TiO2 coatings has a strong effect on the morphology and thickness of as-deposited TiO2 coatings. Fe, Cr and Ni at.% of the substrate gradually changes to 0 when the temperature is increased to 800 °C. The thickness of TiO2 coating is more than 6 μm and uniform by metalloscopy, and the films have a nonstoichiometric composition of Ti3O8 when the deposition temperature is above 800 °C. The anticoking tests show that the TiO2 coating at a deposition temperature of 800 °C is sufficiently thick to cover the cracks and gaps on the surface of blank substrate and cut off the catalytic coke growth effect of the metal substrate. The anticoking ratio of TiO2 coating corresponding to each 5 cm segments is above 65% and the average anticoking ratio of TiO2 coating is up to 76%. Thus, the TiO2 coating can provide a very good protective layer to prevent the substrate from severe coking efficiently.

  2. Solar cells based upon multicrystalline Si with DLC antireflection and passivating coatings

    International Nuclear Information System (INIS)

    Klyui, N.; Litovchenko, V.; Neselevska, L.; Kostylyov, V.; Sarikov, A.; Taraschenko, N.; Kittler, M.; Seifert, W.

    2006-01-01

    The characteristics of multicrystalline Si solar cells covered by diamond-like carbon (DLC) antireflection coatings been experimentally studied. It has been shown that this kind of coating provides a significant increase of the efficiency of solar cells mainly due to the increase of the short-circuit current density. The effects of antireflection and of the surface and bulk passivation on the SC current-voltage characteristics due to the DLC deposition have been investigated theoretically. Physical mechanisms underlying the observed effects have been proposed

  3. Properties of DLC coatings deposited by dc and dc with superimposed pulsed vacuum arc

    International Nuclear Information System (INIS)

    Zavaleyev, V.; Walkowicz, J.; Aksyonov, D.S.; Luchaninov, A.A.; Reshetnyak, E.N.; Strel'nitskij, V.E.

    2014-01-01

    Comparative studies of the structure, mechanical and tribological properties of DLC coatings deposited in DC and DC with superimposed high current pulse modes of operation vacuum-arc plasma source with the graphite cathode are presented. Imposition the pulses of high current on DC vacuum-arc discharge allows both increase the deposition rate of DLC coating and reduce the residual compressive stress in the coatings what promotes substantial improvement the adhesion to the substrate. Effect of vacuum arc plasma filtration with Venetian blind filter on the deposition rate and tribological characteristics of the coatings analyzed.

  4. The effect of nitrogen and oxygen plasma on the wear properties and adhesion strength of the diamond-like carbon film coated on PTFE

    International Nuclear Information System (INIS)

    Ozeki, K.; Hirakuri, K.K.

    2008-01-01

    Diamond-like carbon (DLC) films were deposited on polytetrafluoroethylene (PTFE) using a radiofrequency plasma chemical vapour deposition method. Prior to DLC coating, the PTFE substrates were modified with O 2 and N 2 plasma to enhance the adhesion strength of the DLC film to the substrate. The effect of the plasma pre-treatment on the chemical composition and the surface energy of the plasma pre-treated PTFE surface was investigated by X-ray photoelectron spectroscopy (XPS) and static water contact angle measurement, respectively. A pull-out test and a ball-on-disc test were carried out to evaluate the adhesion strength and the wear properties of the DLC-coated PTFE. In the N 2 plasma pre-treatment, the XPS result indicated that defluorination and the nitrogen grafting occurred on the plasma pre-treated PTFE surface, and the water contact angle decreased with increasing the plasma pre-treatment time. In the O 2 plasma pre-treatment, no grafting of the oxygen occurred, and the water contact angle slightly increased with the treatment time. In the pull-out test, the adhesion strength of the DLC film to the PTFE substrate was improved with the plasma pre-treatment to the PTFE substrate, and N 2 plasma pre-treatment was more effective than the O 2 plasma pre-treatment. In the ball-on-disc test, the DLC film with the N 2 plasma pre-treatment showed good wear resistance, compared with that with O 2 plasma pre-treatment

  5. LARGE AREA FILTERED ARC DEPOSITION OF CARBON AND BORON BASED HARD COATINGS

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Rabi S.

    2003-12-05

    This document is a final report covering work performed under Contract No. DE-FG02-99ER82911 from the Department of Energy under a SBIR Phase II Program. Wear resistant, hard coatings can play a vital role in many engineering applications. The primary goal of this project was to develop coatings containing boron and carbon with hardness greater than 30 GPa and evaluate these coatings for machining applications. UES has developed a number of carbon and boron containing coatings with hardness in the range of 34 to 65 GPa using a combination of filtered cathodic arc and magnetron sputtering. The boron containing coatings were based on TiB2, TiBN, and TiBCN, while the carbon containing coatings ere TiC+C and hydrogen free diamond-like-carbon. Machining tests were performed with single and multilayer coated tools. The turning and milling tests were run at TechSolve Inc., under a subcontract at Ohio State University. Significant increases in tool lives were realized in end milling of H-13 die steel (8X) and titanium alloy (80%) using the TiBN coating. A multilayer TiBN/TiN performed the best in end-milling of highly abrasive Al-Si alloys. A 40% increase in life over the TiAlN benchmark coating was found. Further evaluations of these coatings with commercialization partners are currently in progress.

  6. Structure And Properties Of PVD Coatings Deposited On Cermets

    Directory of Open Access Journals (Sweden)

    Żukowska L.

    2015-06-01

    Full Text Available The main aim of the research is the investigation of the structure and properties of single-layer and gradient coatings of the type (Ti,AlN and Ti(C,N deposited by physical vapour deposition technology (PVD on the cermets substrate.

  7. Vapor deposition on doublet airfoil substrates: Control of coating thickness and microstructure

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, Theron M.; Zhao, Hengbei; Wadley, Haydn N. G., E-mail: haydn@virginia.edu [Department of Materials Science and Engineering, University of Virginia, 395 McCormick Rd., P.O. Box 400745, Charlottesville, Virginia 22904 (United States)

    2015-11-15

    Gas jet assisted vapor deposition processes for depositing coatings are conducted at higher pressures than conventional physical vapor deposition methods, and have shown promise for coating complex shaped substrates including those with non-line-of-sight (NLS) regions on their surface. These regions typically receive vapor atoms at a lower rate and with a wider incident angular distribution than substrate regions in line-of-sight (LS) of the vapor source. To investigate the coating of such substrates, the thickness and microstructure variation along the inner (curved) surfaces of a model doublet airfoil containing both LS and NLS regions has been investigated. Results from atomistic simulations and experiments confirm that the coating's thickness is thinner in flux-shadowed regions than in other regions for all the coating processes investigated. They also indicated that the coatings columnar microstructure and pore volume fraction vary with surface location through the LS to NLS transition zone. A substrate rotation strategy for optimizing the thickness over the entire doublet airfoil surface was investigated, and led to the identification of a process that resulted in only small variation of coating thickness, columnar growth angle, and pore volume fraction on all doublet airfoil surfaces.

  8. GENERAL RULES OF SIC FORMATION IN DIAMOND-CONTAINING COMPOSITION AT LOW PRESSURE

    Directory of Open Access Journals (Sweden)

    A. E. Zhuk

    2007-01-01

    Full Text Available Results of experimental investigations of structure-formation process of «diamond-carbide silicon» composite at low pressure which is obtained by liquid silicon impregnation of a porous blank made of diamond crystals with nano-coatings have made it possible to establish the following general rules of the process concerning a sintering reaction in the coating and composite material: vacuum magnetronic spraying of composite cathodes leads to formation of nano-coating which is made of silicon and hydrogen atoms or clusters, and their subsequent treatment with plasma of glow discharge is accompanied by formation of α-SiC at low temperatures in a hard phase; silicon impregnation at 1500 °C with given pyrolytic carbon in the charge may result in β-SiC matrix formation.The formed «diamond-carbide silicon» composite material contains a frame structure of diamond crystals with nano-coating impregnated by silicon carbide and is characterized by high physical and mechanical properties. 

  9. Tuning properties of long-period gratings by plasma post-processing of their diamond-like carbon nano-overlays

    International Nuclear Information System (INIS)

    Smietana, M; Koba, M; Mikulic, P; Bock, W J

    2014-01-01

    This work presents an application of reactive ion etching (RIE) for effective tuning of spectral response and the refractive index (RI) sensitivity of diamond-like carbon (DLC) nano-coated long-period gratings (LPGs). When oxygen plasma is applied the technique allows for an efficient and well controlled etching of hard and chemically resistant DLC films deposited on optical fibers. We show that optical properties of DLC, especially its refractive index, strongly depend on thickness of the film when it is thinner than 150 nm. The effect of DLC nano-coating deposition and etching on spectral properties of the LPGs is discussed. We have correlated the DLC properties with the shift of the LPG resonance wavelength and have found that both deposition and etching processes took place less effectively than on the electrode when the LPG sample was held above the electrode in the plasma reactor. An advantage of plasma-based etching is a capability for post-processing of the nano-coated structures with a good precision, as well as cleaning the samples and their re-coating according to requested needs. Moreover, the application of RIE allows for post-fabrication tuning of RI sensitivity of the DLC nano-coated LPGs. (paper)

  10. Tuning properties of long-period gratings by plasma post-processing of their diamond-like carbon nano-overlays

    Science.gov (United States)

    Smietana, M.; Koba, M.; Mikulic, P.; Bock, W. J.

    2014-11-01

    This work presents an application of reactive ion etching (RIE) for effective tuning of spectral response and the refractive index (RI) sensitivity of diamond-like carbon (DLC) nano-coated long-period gratings (LPGs). When oxygen plasma is applied the technique allows for an efficient and well controlled etching of hard and chemically resistant DLC films deposited on optical fibers. We show that optical properties of DLC, especially its refractive index, strongly depend on thickness of the film when it is thinner than 150 nm. The effect of DLC nano-coating deposition and etching on spectral properties of the LPGs is discussed. We have correlated the DLC properties with the shift of the LPG resonance wavelength and have found that both deposition and etching processes took place less effectively than on the electrode when the LPG sample was held above the electrode in the plasma reactor. An advantage of plasma-based etching is a capability for post-processing of the nano-coated structures with a good precision, as well as cleaning the samples and their re-coating according to requested needs. Moreover, the application of RIE allows for post-fabrication tuning of RI sensitivity of the DLC nano-coated LPGs.

  11. Ohmic contacts to semiconducting diamond

    Science.gov (United States)

    Zeidler, James R.; Taylor, M. J.; Zeisse, Carl R.; Hewett, C. A.; Delahoussaye, Paul R.

    1990-10-01

    Work was carried out to improve the electron beam evaporation system in order to achieve better deposited films. The basic system is an ion pumped vacuum chamber, with a three-hearth, single-gun e-beam evaporator. Four improvements were made to the system. The system was thoroughly cleaned and new ion pump elements, an e-gun beam adjust unit, and a more accurate crystal monitor were installed. The system now has a base pressure of 3 X 10(exp -9) Torr, and can easily deposit high-melting-temperature metals such as Ta with an accurately controlled thickness. Improved shadow masks were also fabricated for better alignment and control of corner contacts for electrical transport measurements. Appendices include: A Thermally Activated Solid State Reaction Process for Fabricating Ohmic Contacts to Semiconducting Diamond; Tantalum Ohmic Contacts to Diamond by a Solid State Reaction Process; Metallization of Semiconducting Diamond: Mo, Mo/Au, and Mo/Ni/Au; Specific Contact Resistance Measurements of Ohmic Contracts to Diamond; and Electrical Activation of Boron Implanted into Diamond.

  12. Effect of plasma composition on nanocrystalline diamond layers deposited by a microwave linear antenna plasma-enhanced chemical vapour deposition system

    Czech Academy of Sciences Publication Activity Database

    Taylor, Andrew; Ashcheulov, Petr; Čada, Martin; Fekete, Ladislav; Hubík, Pavel; Klimša, Ladislav; Olejníček, Jiří; Remeš, Zdeněk; Jirka, Ivan; Janíček, P.; Bedel-Pereira, E.; Kopeček, Jaromír; Mistrík, J.; Mortet, Vincent

    2015-01-01

    Roč. 212, č. 11 (2015), s. 2418-2423 ISSN 1862-6300 R&D Projects: GA ČR GA13-31783S; GA MŠk LO1409 Grant - others:FUNBIO(XE) CZ.2.16/3.1.00/21568 Institutional support: RVO:68378271 ; RVO:61388955 Keywords : diamond * electrical conductivity * nanocrystalline materials * optical emission spectroscopy * plasma enhanced chemical vapour deposition * SiC Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.648, year: 2015

  13. Resistance to Corrosion of Zirconia Coatings Deposited by Spray Pyrolysis in Nitrided Steel

    Science.gov (United States)

    Cubillos, G. I.; Olaya, J. J.; Bethencourt, M.; Cifredo, G.; Blanco, G.

    2013-10-01

    Coatings of zirconium oxide were deposited onto three types of stainless steel, AISI 316L, 2205, and tool steel AISI D2, using the ultrasonic spray pyrolysis method. The effect of the flux ratio on the process and its influence on the structure and morphology of the coatings were investigated. The coatings obtained, 600 nm thick, were characterized using x-ray diffraction, scanning electron microscopy, confocal microscopy, and atomic force microscopy. The resistance to corrosion of the coatings deposited over steel (not nitrided) and stainless steel nitrided (for 2 h at 823 K) in an ammonia atmosphere was evaluated. The zirconia coating enhances the stainless steel's resistance to corrosion, with the greatest increase in corrosion resistance being observed for tool steel. When the deposition is performed on previously nitrided stainless steel, the morphology of the surface improves and the coating is more homogeneous, which leads to an improved corrosion resistance.

  14. Electrophoretic deposition of PEEK-TiO 2 composite coatings on stainless steel

    KAUST Repository

    Seuß, Sigrid

    2012-03-01

    Electrophoretic deposition (EPD) has been successfully used to deposit composite coatings composed of polyetheretherketone (PEEK) and titanium dioxide (TiO 2) nanoparticles on 316L stainless steel substrates. The suspensions of TiO2 nanoparticles and PEEK microparticles for EPD were prepared in ethanol. PEEK-TiO 2 composite coatings were optimized using suspensions containing 6wt% PEEK-TiO 2 in ethanol with a 3:1 ratio of PEEK to TiO 2 in weight and by applying a potential difference of 30 V for 1 minute. A heat-treatment process of the optimized PEEK-TiO 2 composite coatings was erformed at 335°C for 30 minutes with a heating rate of 10°Cmin -1 to densify the deposits. The EPD coatings were microstructurally evaluated by scanning electron microscopy (SEM). It was demonstrated that EPD is a convenient and rapid method to fabricate PEEK/TiO 2 coatings on stainless steel which are interesting for biomedical applications. © (2012) Trans Tech Publications, Switzerland.

  15. Deposition of antimicrobial coatings on microstereolithography-fabricated microneedles

    Science.gov (United States)

    Gittard, Shaun D.; Miller, Philip R.; Jin, Chunming; Martin, Timothy N.; Boehm, Ryan D.; Chisholm, Bret J.; Stafslien, Shane J.; Daniels, Justin W.; Cilz, Nicholas; Monteiro-Riviere, Nancy A.; Nasir, Adnan; Narayan, Roger J.

    2011-06-01

    Microneedles are small-scale needle-like projections that may be used for transdermal delivery of pharmacologic agents, including protein-containing and nucleic acid-containing agents. Commercial translation of polymeric microneedles would benefit from the use of facile and cost effective fabrication methods. In this study, visible light dynamic mask microstereolithography, a rapid prototyping technique that utilizes digital light projection for selective polymerization of a liquid resin, was used for fabrication of solid microneedle array structures out of an acrylate-based polymer. Pulsed laser deposition was used to deposit silver and zinc oxide coatings on the surfaces of the visible light dynamic mask microstereolithography-fabricated microneedle array structures. Agar diffusion studies were used to demonstrate the antimicrobial activity of the coated microneedle array structures. This study indicates that light-based technologies, including visible light dynamic mask microstereolithography and pulsed laser deposition, may be used to fabricate microneedles with antimicrobial properties for treatment of local skin infections.

  16. Thick CrN/NbN multilayer coating deposited by cathodic arc technique

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Juliano Avelar; Tschiptschin, Andre Paulo; Souza, Roberto Martins, E-mail: antschip@usp.br [Universidade de Sao Paulo (USP), SP (Brazil); Lima, Nelson Batista de [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-01-15

    The production of tribological nanoscale multilayer CrN/NbN coatings up to 6 μm thick by Sputtering/HIPIMS has been reported in literature. However, high demanding applications, such as internal combustion engine parts, need thicker coatings (>30 μm). The production of such parts by sputtering would be economically restrictive due to low deposition rates. In this work, nanoscale multilayer CrN/NbN coatings were produced in a high-deposition rate, industrial-size, Cathodic Arc Physical Vapor Deposition (ARC-PVD) chamber, containing three cathodes in alternate positions (Cr/ Nb/Cr). Four 30 μm thick NbN/CrN multilayer coatings with different periodicities (20, 10, 7.5 and 4 nm) were produced. The coatings were characterized by X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). The multilayer coating system was composed of alternate cubic rock salt CrN and NbN layers, coherently strained due to lattice mismatch. The film grew with columnar morphology through the entire stratified structure. The periodicities adopted were maintained throughout the entire coating. The 20 nm periodicity coating showed separate NbN and CrN peaks in the XRD patterns, while for the lower periodicity (≤10nm) coatings, just one intermediate lattice (d-spacing) was detected. An almost linear increase of hardness with decreasing bilayer period indicates that interfacial effects can dominate the hardening mechanisms. (author)

  17. Novel Bioactive Antimicrobial Lignin Containing Coatings on Titanium Obtained by Electrophoretic Deposition

    Directory of Open Access Journals (Sweden)

    Sanja Erakovic

    2014-07-01

    Full Text Available Hydroxyapatite (HAP is the most suitable biocompatible material for bone implant coatings; its brittleness, however, is a major obstacle, and the reason why research focuses on creating composites with biopolymers. Organosolv lignin (Lig is used for the production of composite coatings, and these composites were examined in this study. Titanium substrate is a key biomedical material due to its well-known properties, but infections of the implantation site still impose a serious threat. One approach to prevent infection is to improve antimicrobial properties of the coating material. Silver doped hydroxyapatite (Ag/HAP and HAP coatings on titanium were obtained by an electrophoretic deposition method in order to control deposited coating mass and morphology by varying applied voltage and deposition time. The effect of lignin on microstructure, morphology and thermal behavior of biocomposite coatings was investigated. The results showed that higher lignin concentrations protect the HAP lattice during sintering, improving coating stability. The corrosion stability was evaluated in simulated body fluid (SBF at 37 °C. Newly formed plate-shaped carbonate-HAP was detected, indicating enhanced bioactive performance. The antimicrobial efficiency of Ag/HAP/Lig was confirmed by its higher reduction of bacteria Staphylococcus aureus TL (S. aureus TL than of HAP/Lig coating. Cytotoxicity assay revealed that both coatings can be classified as non-toxic against healthy immunocompetent peripheral blood mononuclear cells (PBMC.

  18. Modeling of gas flow and deposition profile in HWCVD processes

    Energy Technology Data Exchange (ETDEWEB)

    Pflug, Andreas; Höfer, Markus; Harig, Tino; Armgardt, Markus; Britze, Chris; Siemers, Michael; Melzig, Thomas; Schäfer, Lothar

    2015-11-30

    Hot wire chemical vapor deposition (HWCVD) is a powerful technology for deposition of high quality films on large area, where drawbacks of plasma based technology such as defect generation by ion bombardment and high equipment costs are omitted. While processes for diamond coatings using H{sub 2} and CH{sub 4} as precursor have been investigated in detail since 1990 and have been transferred to industry, research also focuses on silicon based coatings with H{sub 2}, SiH{sub 4} and NH{sub 3} as process gases. HWCVD of silicon based coatings is a promising alternative for state-of-the-art radiofrequency-plasma enhanced chemical vapor deposition reactors. The film formation in HWCVD results from an interaction of several concurrent chemical reactions such as gas phase chemistry, film deposition, abstraction of surplus hydrogen bonds and etching by atomic hydrogen. Since there is no easy relation between process parameters and resulting deposition profiles, substantial experimental effort is required to optimize the process for a given film specification and the desired film uniformity. In order to obtain a deeper understanding of the underlying mechanisms and to enable an efficient way of process optimization, simulation methods come into play. While diamond deposition occurs at pressures in the range of several kPa HWCVD deposition of Si based coatings operates at pressures in the 0.1–30 Pa range. In this pressure regime, particle based simulation methods focused on solving the Boltzmann equation are computationally feasible. In comparison to computational fluid dynamics this yields improved accuracy even near small gaps or orifices, where characteristic geometric dimensions approach the order of the mean free path of gas molecules. At Fraunhofer IST, a parallel implementation of the Direct Simulation Monte Carlo (DSMC) method extended by a reactive wall chemistry model is developed. To demonstrate the feasibility of three-dimensional simulation of HWCVD processes

  19. The development of chemically vapor deposited mullite coatings for the corrosion protection of SiC

    Energy Technology Data Exchange (ETDEWEB)

    Auger, M.; Hou, P.; Sengupta, A.; Basu, S.; Sarin, V. [Boston Univ., MA (United States)

    1998-05-01

    Crystalline mullite coatings have been chemically vapor deposited onto SiC substrates to enhance the corrosion and oxidation resistance of the substrate. Current research has been divided into three distinct areas: (1) Development of the deposition processing conditions for increased control over coating`s growth rate, microstructure, and morphology; (2) Analysis of the coating`s crystal structure and stability; (3) The corrosion resistance of the CVD mullite coating on SiC.

  20. Magnetic field effects on coating deposition rate and surface morphology coatings using magnetron sputtering

    International Nuclear Information System (INIS)

    Yang, Yu-Sen; Huang, Wesley

    2010-01-01

    Chromium nitride coatings exhibit superior hardness, excellent wear and oxidation resistance, and are widely applied in the die and mold industries. The aim of this study was to investigate magnetic field effects on the deposition rate and surface morphology of chromium nitride coatings deposited by magnetron sputtering. Four types of magnetic field configurations, including the magnetron sputtering system, SNSN, SNNN, and intermediate magnetron modification, are discussed in this paper. SKD11 cold work die steel and a silicon (100) chip were used as substrates in the chromium nitride depositions. The process parameters, such as target current, substrate bias, and the distance between the substrate and target, are at fixed conditions, except for the magnetic arrangement type. The experimental results showed that the deposition rates of the four types of magnetic field configurations were 1.06, 1.38, 1.67 and 1.26 µm h −1 , respectively. In these cases, the SNNN type performs more than 58% faster than the unbalanced magnetron configuration does for the deposition rate. The surface morphology of chromium nitride films was also examined by SEM and is discussed in this paper

  1. Tribological investigation of diamond-like carbon coated micro-dimpled surface under bovine serum and osteoarthritis oriented synovial fluid

    International Nuclear Information System (INIS)

    Ghosh, Subir; Roy, Taposh; Pingguan-Murphy, Belinda; Choudhury, Dipankar; Bin Mamat, Azuddin; Masjuki, H H

    2015-01-01

    Osteoarthritis-oriented synovial fluid (OASF), i.e., that typical of a patient with osteoarthritis, has different physical and biological characteristics than bovine serum (BS), a lubricant widely used in biotribological investigations. Micro-dimpled and diamond-like carbon- (DLC) coated surfaces are key emerging interfaces for orthopedic implants. In this study, tribological performances of dimpled surfaces, with and without DLC coating, have been investigated under both BS and OASF. The friction tests were performed utilizing a pin on a disk tribometer, whereas contact pressure, speed, and temperature were simulated to a ‘medium walking gait’ of hip joint conditions. The mechanical properties of the specimen and the physical properties of the lubricant were characterized before the friction test. Raman analysis was conducted to identify the coating condition both before and after the test. The DLC-coated dimpled surface showed maximum hardness and residual stress. A DLC-coated dimpled surface under an OASF lubricated condition yielded a lower friction coefficient and wear compared to those of plain and dimpled specimens. The higher graphitization of coated materials with increasing load was confirmed by Raman spectroscopy. (paper)

  2. Tribological investigation of diamond-like carbon coated micro-dimpled surface under bovine serum and osteoarthritis oriented synovial fluid

    Science.gov (United States)

    Ghosh, Subir; Choudhury, Dipankar; Roy, Taposh; Mamat, Azuddin Bin; Masjuki, H. H.; Pingguan-Murphy, Belinda

    2015-06-01

    Osteoarthritis-oriented synovial fluid (OASF), i.e., that typical of a patient with osteoarthritis, has different physical and biological characteristics than bovine serum (BS), a lubricant widely used in biotribological investigations. Micro-dimpled and diamond-like carbon- (DLC) coated surfaces are key emerging interfaces for orthopedic implants. In this study, tribological performances of dimpled surfaces, with and without DLC coating, have been investigated under both BS and OASF. The friction tests were performed utilizing a pin on a disk tribometer, whereas contact pressure, speed, and temperature were simulated to a ‘medium walking gait’ of hip joint conditions. The mechanical properties of the specimen and the physical properties of the lubricant were characterized before the friction test. Raman analysis was conducted to identify the coating condition both before and after the test. The DLC-coated dimpled surface showed maximum hardness and residual stress. A DLC-coated dimpled surface under an OASF lubricated condition yielded a lower friction coefficient and wear compared to those of plain and dimpled specimens. The higher graphitization of coated materials with increasing load was confirmed by Raman spectroscopy.

  3. Diamond Growth in the Subduction Factory

    Science.gov (United States)

    Bureau, H.; Frost, D. J.; Bolfan-Casanova, N.; Leroy, C.; Estève, I.

    2014-12-01

    Natural diamonds are fabulous probes of the deep Earth Interior. They are the evidence of the deep storage of volatile elements, carbon at first, but also hydrogen and chlorine trapped as hydrous fluids in inclusions. The study of diamond growth processes in the lithosphere and mantle helps for our understanding of volatile elements cycling between deep reservoirs. We know now that inclusion-bearing diamonds similar to diamonds found in nature (i.e. polycrystalline, fibrous and coated diamonds) can grow in hydrous fluids or melts (Bureau et al., GCA 77, 202-214, 2012). Therefore, we propose that the best environment to promote such diamonds is the subduction factory, where highly hydrous fluids or melts are present. When oceanic plates are subducted in the lithosphere, they carry an oceanic crust soaked with seawater. While the slabs are traveling en route to the mantle, dehydration processes generate saline fluids highly concentrated in NaCl. In the present study we have experimentally shown that diamonds can grow from the saline fluids (up to 30 g/l NaCl in water) generated in subducted slabs. We have performed multi-anvil press experiments at 6-7 GPa and from 1300 to 1400°C during 6:00 hours to 30:00 hours. We observed large areas of new diamond grown in epitaxy on pure diamond seeds in salty hydrous carbonated melts, forming coated gems. The new rims are containing multi-component primary inclusions. Detailed characterizations of the diamonds and their inclusions have been performed and will be presented. These experimental results suggest that multi-component salty fluids of supercritical nature migrate with the slabs, down to the deep mantle. Such fluids may insure the first stage of the deep Earth's volatiles cycling (C, H, halogen elements) en route to the transition zone and the lower mantle. We suggest that the subduction factory may also be a diamond factory.

  4. Surface modification of reverse osmosis desalination membranes by thin-film coatings deposited by initiated chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Ozaydin-Ince, Gozde, E-mail: gozdeince@sabanciuniv.edu [Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Matin, Asif, E-mail: amatin@mit.edu [Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Khan, Zafarullah, E-mail: zukhan@mit.edu [Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Zaidi, S.M. Javaid, E-mail: zaidismj@kfupm.edu.sa [Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Gleason, Karen K., E-mail: kkgleasn@mit.edu [Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

    2013-07-31

    Thin-film polymeric reverse osmosis membranes, due to their high permeation rates and good salt rejection capabilities, are widely used for seawater desalination. However, these membranes are prone to biofouling, which affects their performance and efficiency. In this work, we report a method to modify the membrane surface without damaging the active layer or significantly affecting the performance of the membrane. Amphiphilic copolymer films of hydrophilic hydroxyethylmethacrylate and hydrophobic perfluorodecylacrylate (PFA) were synthesized and deposited on commercial RO membranes using an initiated chemical vapor deposition technique which is a polymer deposition technique that involves free-radical polymerization initiated by gas-phase radicals. Relevant surface characteristics such as hydrophilicity and roughness could be systematically controlled by varying the polymer chemistry. Increasing the hydrophobic PFA content in the films leads to an increase in the surface roughness and hydrophobicity. Furthermore, the surface morphology studies performed using the atomic force microscopy show that as the thickness of the coating increases average surface roughness increases. Using this knowledge, the coating thickness and chemistry were optimized to achieve high permeate flux and to reduce cell attachment. Results of the static bacterial adhesion tests show that the attachment of bacterial cells is significantly reduced on the coated membranes. - Highlights: • Thin films are deposited on reverse osmosis membranes. • Amphiphilic thin films are resistant to protein attachment. • The permeation performance of the membranes is not affected by the coating. • The thin film coatings delayed the biofouling.

  5. Diamond bio electronics.

    Science.gov (United States)

    Linares, Robert; Doering, Patrick; Linares, Bryant

    2009-01-01

    The use of diamond for advanced applications has been the dream of mankind for centuries. Until recently this dream has been realized only in the use of diamond for gemstones and abrasive applications where tons of diamonds are used on an annual basis. Diamond is the material system of choice for many applications, but its use has historically been limited due to the small size, high cost, and inconsistent (and typically poor) quality of available diamond materials until recently. The recent development of high quality, single crystal diamond crystal growth via the Chemical Vapor Deposition (CVD) process has allowed physcists and increasingly scientists in the life science area to think beyond these limitations and envision how diamond may be used in advanced applications ranging from quantum computing, to power generation and molecular imaging, and eventually even diamond nano-bots. Because of diamond's unique properties as a bio-compatible material, better understanding of diamond's quantum effects and a convergence of mass production, semiconductor-like fabrication process, diamond now promises a unique and powerful key to the realization of the bio-electronic devices being envisioned for the new era of medical science. The combination of robust in-the-body diamond based sensors, coupled with smart bio-functionalized diamond devices may lead to diamond being the platform of choice for bio-electronics. This generation of diamond based bio-electronic devices would contribute substantially to ushering in a paradigm shift for medical science, leading to vastly improved patient diagnosis, decrease of drug development costs and risks, and improved effectiveness of drug delivery and gene therapy programs through better timed and more customized solutions.

  6. Surface smoothening effects on growth of diamond films

    Science.gov (United States)

    Reshi, Bilal Ahmad; Kumar, Shyam; Kartha, Moses J.; Varma, Raghava

    2018-04-01

    We have carried out a detailed study of the growth dynamics of the diamond film during initial time on diamond substrates. The diamond films are deposited using Microwave Plasma Chemical Vapor Deposition (MPCVD) method for different times. Surface morphology and its correlation with the number of hours of growth of thin films was invested using atomic force microscopy (AFM). Diamond films have smooth interface with average roughness of 48.6873nm. The initial growth dynamics of the thin film is investigated. Interestingly, it is found that there is a decrease in the surface roughness of the film. Thus a smoothening effect is observed in the grown films. The film enters into the growth regime in the later times. Our results also find application in building diamond detector.

  7. Galvanic deposition and characterization of brushite/hydroxyapatite coatings on 316L stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Blanda, Giuseppe [Laboratorio di Chimica Fisica Applicata, Dipartimento di Ingegneria Chimica Gestionale Informatica Meccanica, Università di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Brucato, Valerio; Pavia, Francesco Carfì; Greco, Silvia [Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Piazza, Salvatore; Sunseri, Carmelo [Laboratorio di Chimica Fisica Applicata, Dipartimento di Ingegneria Chimica Gestionale Informatica Meccanica, Università di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Inguanta, Rosalinda, E-mail: rosalinda.inguanta@unipa.it [Laboratorio di Chimica Fisica Applicata, Dipartimento di Ingegneria Chimica Gestionale Informatica Meccanica, Università di Palermo, Viale delle Scienze, 90128 Palermo (Italy)

    2016-07-01

    In this work, brushite and brushite/hydroxyapatite (BS, CaHPO{sub 4}·H{sub 2}O; HA, Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2}) coatings were deposited on 316L stainless steel (316LSS) from a solution containing Ca(NO{sub 3}){sub 2}·4H{sub 2}O and NH{sub 4}H{sub 2}PO{sub 4} by a displacement reaction based on a galvanic contact, where zinc acts as sacrificial anode. Driving force for the cementation reaction arises from the difference in the electrochemical standard potentials of two different metallic materials (316LSS and Zn) immersed in an electrolyte, so forming a galvanic contact leading to the deposition of BS/HA on nobler metal. We found that temperature and deposition time affect coating features (morphology, structure, and composition). Deposits were characterized by means of several techniques. The morphology was investigated by scanning electron microscopy, the elemental composition was obtained by X-ray energy dispersive spectroscopy, whilst the structure was identified by Raman spectroscopy and X-ray diffraction. BS was deposited at all investigated temperatures covering the 316LSS surface. At low and moderate temperature, BS coatings were compact, uniform and with good crystalline degree. On BS layers, HA crystals were obtained at 50 °C for all deposition times, while at 25 °C, its presence was revealed only after long deposition time. Electrochemical studies show remarkable improvement in corrosion resistance. - Highlights: • Brushite/hydroxyapatite coatings were obtained by a galvanic deposition method. • Galvanic deposition is simple and cheap and does not require external power supply. • Temperature is a key parameter to control composition and morphology of coatings. • Ca/P ratio changes with deposition time, from about 1 up to an optimum value of 1.7. • Compact and adherent layer covering substrate surface were obtained on 316LSS.

  8. Galvanic deposition and characterization of brushite/hydroxyapatite coatings on 316L stainless steel

    International Nuclear Information System (INIS)

    Blanda, Giuseppe; Brucato, Valerio; Pavia, Francesco Carfì; Greco, Silvia; Piazza, Salvatore; Sunseri, Carmelo; Inguanta, Rosalinda

    2016-01-01

    In this work, brushite and brushite/hydroxyapatite (BS, CaHPO_4·H_2O; HA, Ca_1_0(PO_4)_6(OH)_2) coatings were deposited on 316L stainless steel (316LSS) from a solution containing Ca(NO_3)_2·4H_2O and NH_4H_2PO_4 by a displacement reaction based on a galvanic contact, where zinc acts as sacrificial anode. Driving force for the cementation reaction arises from the difference in the electrochemical standard potentials of two different metallic materials (316LSS and Zn) immersed in an electrolyte, so forming a galvanic contact leading to the deposition of BS/HA on nobler metal. We found that temperature and deposition time affect coating features (morphology, structure, and composition). Deposits were characterized by means of several techniques. The morphology was investigated by scanning electron microscopy, the elemental composition was obtained by X-ray energy dispersive spectroscopy, whilst the structure was identified by Raman spectroscopy and X-ray diffraction. BS was deposited at all investigated temperatures covering the 316LSS surface. At low and moderate temperature, BS coatings were compact, uniform and with good crystalline degree. On BS layers, HA crystals were obtained at 50 °C for all deposition times, while at 25 °C, its presence was revealed only after long deposition time. Electrochemical studies show remarkable improvement in corrosion resistance. - Highlights: • Brushite/hydroxyapatite coatings were obtained by a galvanic deposition method. • Galvanic deposition is simple and cheap and does not require external power supply. • Temperature is a key parameter to control composition and morphology of coatings. • Ca/P ratio changes with deposition time, from about 1 up to an optimum value of 1.7. • Compact and adherent layer covering substrate surface were obtained on 316LSS.

  9. Modified DLC coatings prepared in a large-scale reactor by dual microwave/pulsed-DC plasma-activated chemical vapour deposition

    International Nuclear Information System (INIS)

    Corbella, C.; Bialuch, I.; Kleinschmidt, M.; Bewilogua, K.

    2008-01-01

    Diamond-Like Carbon (DLC) films find abundant applications as hard and protective coatings due to their excellent mechanical and tribological performances. The addition of new elements to the amorphous DLC matrix tunes the properties of this material, leading to an extension of its scope of applications. In order to scale up their production to a large plasma reactor, DLC films modified by silicon and oxygen additions have been grown in an industrial plant of 1m 3 by means of pulsed-DC plasma-activated chemical vapour deposition (PACVD). The use of an additional microwave (MW) source has intensified the glow discharge, partly by electron cyclotron resonance (ECR), accelerating therefore the deposition process. Hence, acetylene, tetramethylsilane (TMS) and hexamethyldisiloxane (HMDSO) constituted the respective gas precursors for the deposition of a-C:H (DLC), a-C:H:Si and a-C:H:Si:O films by dual MW/pulsed-DC PACVD. This work presents systematic studies of the deposition rate, hardness, adhesion, abrasive wear and water contact angle aimed to optimize the technological parameters of deposition: gas pressure, relative gas flow of the monomers and input power. This study has been completed with measures of the atomic composition of the samples. Deposition rates around 1 μm/h, typical for standard processes held in the large reactor, were increased about by a factor 10 when the ionization source has been operated in ECR mode

  10. Effects of heat treatment on the microstructure of amorphous boron carbide coating deposited on graphite substrates by chemical vapor deposition

    International Nuclear Information System (INIS)

    Li Siwei; Zeng Bin; Feng Zude; Liu Yongsheng; Yang Wenbin; Cheng Laifei; Zhang Litong

    2010-01-01

    A two-layer boron carbide coating is deposited on a graphite substrate by chemical vapor deposition from a CH 4 /BCl 3 /H 2 precursor mixture at a low temperature of 950 o C and a reduced pressure of 10 KPa. Coated substrates are annealed at 1600 o C, 1700 o C, 1800 o C, 1900 o C and 2000 o C in high purity argon for 2 h, respectively. Structural evolution of the coatings is explored by electron microscopy and spectroscopy. Results demonstrate that the as-deposited coating is composed of pyrolytic carbon and amorphous boron carbide. A composition gradient of B and C is induced in each deposition. After annealing, B 4 C crystallites precipitate out of the amorphous boron carbide and grow to several hundreds nanometers by receiving B and C from boron-doped pyrolytic carbon. Energy-dispersive spectroscopy proves that the crystallization is controlled by element diffusion activated by high temperature annealing, after that a larger concentration gradient of B and C is induced in the coating. Quantified Raman spectrum identifies a graphitization enhancement of pyrolytic carbon. Transmission electron microscopy exhibits an epitaxial growth of B 4 C at layer/layer interface of the annealed coatings. Mechanism concerning the structural evolution on the basis of the experimental results is proposed.

  11. Microstructure and properties of duplex (Ti:N)-DLC/MAO coating on magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Wei; Ke, Peiling [Ningbo Key Laboratory of Marine Protection Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Fang, Yong [Sir Run Run Shaw Hospital, School of Medicine, Zhe Jiang University, Zhejiang 310016 (China); Zheng, He [Ningbo Key Laboratory of Marine Protection Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Wang, Aiying, E-mail: aywang@nimte.ac.cn [Ningbo Key Laboratory of Marine Protection Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

    2013-04-01

    Ti and N co-doped diamond-like carbon ((Ti:N)-DLC) film was deposited on the MAO coated substrate using a hybrid beam deposition system, which consists of a DC magnetron sputtering of Ti target and a linear ion source (LIS) with C{sub 2}H{sub 2} and N{sub 2} precursor gas. The microstructure and properties of the duplex (Ti:N)-DLC/MAO coating were investigated. Results indicate that the (Ti:N)-DLC top film with TiN crystalline phase was formed. Ti and N co-doping resulted in the increasing I{sub D}/I{sub G} ratio. The significant improvement in the wear and corrosion resistance of duplex (Ti:N)-DLC/MAO coating was mainly attributed to the increased binding strength, lubrication characteristics and chemical inertness of (Ti:N)-DLC top film. The superior low-friction and anti-corrosion properties of duplex (Ti:N)-DLC/MAO coating make it a good candidate as protective coating on magnesium alloy.

  12. Chemical vapor deposition: A technique for applying protective coatings

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, T.C. Sr.; Bowman, M.G.

    1979-01-01

    Chemical vapor deposition is discussed as a technique for applying coatings for materials protection in energy systems. The fundamentals of the process are emphasized in order to establish a basis for understanding the relative advantages and limitations of the technique. Several examples of the successful application of CVD coating are described. 31 refs., and 18 figs.

  13. Cyclic voltammetry response of an undoped CVD diamond electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Fabisiak, K., E-mail: kfab@ukw.edu.pl [Institute of Physics, Kazimierz Wielki University, Powstancow Wielkopolskich 2, 85-090 Bydgoszcz (Poland); Torz-Piotrowska, R. [Faculty of Chemical Technology and Engineering, UTLS Seminaryjna 3, 85-326 Bydgoszcz (Poland); Staryga, E. [Institute of Physics, Technical University of Lodz, Wolczanska 219, 90-924 Lodz (Poland); Szybowicz, M. [Faculty of Technical Physics, Poznan University of Technology, Nieszawska 13A, 60-965 Poznan (Poland); Paprocki, K.; Popielarski, P.; Bylicki, F. [Institute of Physics, Kazimierz Wielki University, Powstancow Wielkopolskich 2, 85-090 Bydgoszcz (Poland); Wrzyszczynski, A. [Institute of Physics, Technical University of Lodz, Wolczanska 219, 90-924 Lodz (Poland)

    2012-09-01

    Highlights: Black-Right-Pointing-Pointer Correlation was found between diamond quality and its electrochemical performance. Black-Right-Pointing-Pointer The electrode sensitivity depends on the content of sp{sup 2} carbon phase in diamond layer. Black-Right-Pointing-Pointer The sp{sup 2} carbon phase content has little influence on the CV peak separation ({Delta}E{sub p}). - Abstract: The polycrystalline undoped diamond layers were deposited on tungsten wire substrates by using hot filament chemical vapor deposition (HFCVD) technique. As a working gas the mixture of methanol in excess of hydrogen was used. The morphologies and quality of as-deposited films were monitored by means of scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy respectively. The electrochemical activity of the obtained diamond layers was monitored by using cyclic voltammetry measurements. Analysis of the ferrocyanide-ferricyanide couple at undoped diamond electrode suggests that electrochemical reaction at diamond electrode has a quasireversibile character. The ratio of the anodic and cathodic peak currents was always close to unity. In this work we showed that the amorphous carbon admixture in the CVD diamond layer has a crucial influence on its electrochemical performance.

  14. Coating of carbon short fibers with thin ceramic layers by chemical vapor deposition

    International Nuclear Information System (INIS)

    Hackl, Gerrit; Gerhard, Helmut; Popovska, Nadejda

    2006-01-01

    Carbon short fiber bundles with a length of 6 mm were uniformly coated using specially designed, continuous chemical vapor deposition (CVD) equipment. Thin layers of titanium nitride, silicon nitride (SiC) and pyrolytic carbon (pyC) were deposited onto several kilograms of short fibers in this large scale CVD reactor. Thermo-gravimetric analyses and scanning electron microscopy investigations revealed layer thicknesses between 20 and 100 nm on the fibers. Raman spectra of pyC coated fibers show a change of structural order depending on the CVD process parameters. For the fibers coated with SiC, Raman investigations showed a deposition of amorphous SiC. The coated carbon short fibers will be applied as reinforcing material in composites with ceramic and metallic matrices

  15. The effectiveness of Ti implants as barriers to carbon diffusion in Ti implanted steel under CVD diamond deposition conditions

    Energy Technology Data Exchange (ETDEWEB)

    Weiser, P.S.; Prawer, S. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Hoffman, A. [Technion-Israel Inst. of Tech., Haifa (Israel). Dept. of Chemistry; Evan, P.J. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Paterson, P.J.K. [Royal Melbourne Inst. of Tech., VIC (Australia)

    1993-12-31

    The growth of chemical vapour deposited (CVD) diamond onto iron based substrates complicated by preferential soot formation and carbon diffusion into the substrate [1], leading to poor quality films and poor adhesion. In the initial stages of exposure to a microwave plasma, a layer of graphite is rapidly formed on an untreated Fe based substrate. Once this graphite layer reaches a certain thickness, reasonable quality diamond nucleates and grows upon it. However, the diamond film easily delaminates from the substrate, the weak link being the graphitic layer. Following an initial success in using a TiN barrier layer to inhibit the formation of such a graphitic layer the authors report on attempts to use an implanted Ti layer for the same purpose. This work was prompted by observation that, although the TiN proved to be an extremely effective diffusion barrier, adhesion may be further enhanced by the formation of a TiC interface layer between the diamond film and the Fe substrate. 3 refs., 6 figs.

  16. The effectiveness of Ti implants as barriers to carbon diffusion in Ti implanted steel under CVD diamond deposition conditions

    International Nuclear Information System (INIS)

    Weiser, P.S.; Prawer, S.; Paterson, P.J.K.

    1993-01-01

    The growth of chemical vapour deposited (CVD) diamond onto iron based substrates complicated by preferential soot formation and carbon diffusion into the substrate [1], leading to poor quality films and poor adhesion. In the initial stages of exposure to a microwave plasma, a layer of graphite is rapidly formed on an untreated Fe based substrate. Once this graphite layer reaches a certain thickness, reasonable quality diamond nucleates and grows upon it. However, the diamond film easily delaminates from the substrate, the weak link being the graphitic layer. Following an initial success in using a TiN barrier layer to inhibit the formation of such a graphitic layer the authors report on attempts to use an implanted Ti layer for the same purpose. This work was prompted by observation that, although the TiN proved to be an extremely effective diffusion barrier, adhesion may be further enhanced by the formation of a TiC interface layer between the diamond film and the Fe substrate. 3 refs., 6 figs

  17. The effectiveness of Ti implants as barriers to carbon diffusion in Ti implanted steel under CVD diamond deposition conditions

    Energy Technology Data Exchange (ETDEWEB)

    Weiser, P S; Prawer, S [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Hoffman, A [Technion-Israel Inst. of Tech., Haifa (Israel). Dept. of Chemistry; Evan, P J [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Paterson, P J.K. [Royal Melbourne Inst. of Tech., VIC (Australia)

    1994-12-31

    The growth of chemical vapour deposited (CVD) diamond onto iron based substrates complicated by preferential soot formation and carbon diffusion into the substrate [1], leading to poor quality films and poor adhesion. In the initial stages of exposure to a microwave plasma, a layer of graphite is rapidly formed on an untreated Fe based substrate. Once this graphite layer reaches a certain thickness, reasonable quality diamond nucleates and grows upon it. However, the diamond film easily delaminates from the substrate, the weak link being the graphitic layer. Following an initial success in using a TiN barrier layer to inhibit the formation of such a graphitic layer the authors report on attempts to use an implanted Ti layer for the same purpose. This work was prompted by observation that, although the TiN proved to be an extremely effective diffusion barrier, adhesion may be further enhanced by the formation of a TiC interface layer between the diamond film and the Fe substrate. 3 refs., 6 figs.

  18. Nickel coating on high strength low alloy steel by pulse current deposition

    Science.gov (United States)

    Nigam, S.; Patel, S. K.; Mahapatra, S. S.; Sharma, N.; Ghosh, K. S.

    2015-02-01

    Nickel is a silvery-white metal mostly used to enhance the value, utility, and lifespan of industrial equipment and components by protecting them from corrosion. Nickel is commonly used in the chemical and food processing industries to prevent iron from contamination. Since the properties of nickel can be controlled and varied over broad ranges, nickel plating finds numerous applications in industries. In the present investigation, pulse current electro-deposition technique has been used to deposit nickel on a high strength low alloy (HSLA) steel substrate.Coating of nickel is confirmed by X-ray diffraction (XRD) and EDAX analysis. Optical microscopy and SEM is used to assess the coating characteristics. Electrochemical polarization study has been carried out to study the corrosion behaviour of nickel coating and the polarisation curves have revealed that current density used during pulse electro-deposition plays a vital role on characteristics of nickel coating.

  19. Metal-doped diamond-like carbon films synthesized by filter-arc deposition

    International Nuclear Information System (INIS)

    Weng, K.-W.; Chen, Y.-C.; Lin, T.-N.; Wang, D.-Y.

    2006-01-01

    Diamond-like carbon (DLC) thin films are extensively utilized in the semiconductor, electric and cutting machine industries owing to their high hardness, high elastic modulus, low friction coefficients and high chemical stability. DLC films are prepared by ion beam-assisted deposition (BAD), sputter deposition, plasma-enhanced chemical vapor deposition (PECVD), cathodic arc evaporation (CAE), and filter arc deposition (FAD). The major drawbacks of these methods are the degraded hardness associated with the low sp 3 /sp 2 bonding ratio, the rough surface and poor adhesion caused by the presence of particles. In this study, a self-developed filter arc deposition (FAD) system was employed to prepare metal-containing DLC films with a low particle density. The relationships between the DLC film properties, such as film structure, surface morphology and mechanical behavior, with variation of substrate bias and target current, are examined. Experimental results demonstrate that FAD-DLC films have a lower ratio, suggesting that FAD-DLC films have a greater sp 3 bonding than the CAE-DLC films. FAD-DLC films also exhibit a low friction coefficient of 0.14 and half of the number of surface particles as in the CAE-DLC films. Introducing a CrN interfacial layer between the substrate and the DLC films enables the magnetic field strength of the filter to be controlled to improve the adhesion and effectively eliminate the contaminating particles. Accordingly, the FAD system improves the tribological properties of the DLC films

  20. Iridium Coating Deposited by Double Glow Plasma Technique — Effect of Glow Plasma on Structure of Coating at Single Substrate Edge

    International Nuclear Information System (INIS)

    Wu Wangping; Chen Zhaofeng; Liu Yong

    2012-01-01

    Double glow plasma technique has a high deposition rate for preparing iridium coating. However, the glow plasma can influence the structure of the coating at the single substrate edge. In this study, the iridium coating was prepared by double glow plasma on the surface of single niobium substrate. The microstructure of iridium coating at the substrate edge was observed by scanning electron microscopy. The composition of the coating was confirmed by energy dispersive spectroscopy and X-ray diffraction. There was a boundary between the coating and the substrate edge. The covered area for the iridium coating at the substrate edge became fewer and fewer from the inner area to the outer flange-area. The bamboo sprout-like particles on the surface of the substrate edge were composed of elemental niobium. The substrate edge was composed of the Nb coating and there was a transition zone between the Ir coating and the Nb coating. The interesting phenomenon of the substrate edge could be attributed to the effects of the bias voltages and the plasma cloud in the deposition chamber. The substrate edge effect could be mitigated or eliminated by adding lots of small niobium plates around the substrate in a deposition process. (plasma technology)

  1. Giant Negative Piezoresistive Effect in Diamond-like Carbon and Diamond-like Carbon-Based Nickel Nanocomposite Films Deposited by Reactive Magnetron Sputtering of Ni Target

    DEFF Research Database (Denmark)

    Meškinis, Šaru Nas; Gudaitis, Rimantas; Šlapikas, Kęstutis

    2018-01-01

    deposited by either reactive HIPIMS or dc magnetron sputtering of Ni target was explained by possible clustering of the sp2-bonded carbon and/or formation of areas with the decreased hydrogen content. It was suggested that the tensile stress-induced rearrangements of these conglomerations have resulted......Piezoresistive properties of hydrogenated diamond-like carbon (DLC) and DLC-based nickel nanocomposite (DLC:Ni) films were studied in the range of low concentration of nickel nanoparticles. The films were deposited by reactive high power pulsed magnetron sputtering (HIPIMS) of Ni target, and some...... samples were deposited by direct current (dc) reactive magnetron sputtering for comparison purposes. Raman scattering spectroscopy, energy-dispersive X-ray spectrometry (EDS), and X-ray photoelectron spectroscopy (XPS) were used to study the structure and chemical composition of the films. A four...

  2. High energy ion beam induced modifications in diamond and diamond like carbon thin films

    International Nuclear Information System (INIS)

    Dilawar, N.; Sah, S.; Mehta, B.R.; Vankar, V.D.

    1996-01-01

    Diamond and DLC films deposited using hot-filament chemical vapour deposition technique at various parameters were irradiated with 50 MeV Si 4+ ions. The resulting microstructural changes were studied using X-ray diffraction and scanning electron microscopy. All the samples showed the development of β-SiC and hexagonal carbon phases at the expense of the diamond/DLC phase. The ERD analysis was carried out to determine the hydrogen concentration and its distribution in DLC films. The absolute hydrogen concentration in DLC samples is of the order of 10 22 atoms/cm 3 which gets depleted on irradiation. The DLC samples show a clear dependence of hydrogen content on the deposition parameters. (author)

  3. Electro-chemical deposition of nano hydroxyapatite-zinc coating on titanium metal substrate.

    Science.gov (United States)

    El-Wassefy, N A; Reicha, F M; Aref, N S

    2017-08-13

    Titanium is an inert metal that does not induce osteogenesis and has no antibacterial properties; it is proposed that hydroxyapatite coating can enhance its bioactivity, while zinc can contribute to antibacterial properties and improve osseointegration. A nano-sized hydroxyapatite-zinc coating was deposited on commercially pure titanium using an electro-chemical process, in order to increase its surface roughness and enhance adhesion properties. The hydroxyapatite-zinc coating was attained using an electro-chemical deposition in a solution composed of a naturally derived calcium carbonate, di-ammonium hydrogen phosphate, with a pure zinc metal as the anode and titanium as the cathode. The applied voltage was -2.5 for 2 h at a temperature of 85 °C. The resultant coating was characterized for its surface morphology and chemical composition using a scanning electron microscope (SEM), energy dispersive x-ray spectroscope (EDS), and Fourier transform infrared (FT-IR) spectrometer. The coated specimens were also evaluated for their surface roughness and adhesion quality. Hydroxyapatite-zinc coating had shown rosette-shaped, homogenous structure with nano-size distribution, as confirmed by SEM analysis. FT-IR and EDS proved that coatings are composed of hydroxyapatite (HA) and zinc. The surface roughness assessment revealed that the coating procedure had significantly increased average roughness (Ra) than the control, while the adhesive tape test demonstrated a high-quality adhesive coat with no laceration on tape removal. The developed in vitro electro-chemical method can be employed for the deposition of an even thickness of nano HA-Zn adhered coatings on titanium substrate and increases its surface roughness significantly.

  4. Status and applications of diamond and diamond-like materials: An emerging technology

    Science.gov (United States)

    1990-01-01

    Recent discoveries that make possible the growth of crystalline diamond by chemical vapor deposition offer the potential for a wide variety of new applications. This report takes a broad look at the state of the technology following from these discoveries in relation to other allied materials, such as high-pressure diamond and cubic boron nitride. Most of the potential defense, space, and commercial applications are related to diamond's hardness, but some utilize other aspects such as optical or electronic properties. The growth processes are reviewed, and techniques for characterizing the resulting materials' properties are discussed. Crystalline diamond is emphasized, but other diamond-like materials (silicon carbide, amorphous carbon containing hydrogen) are also examined. Scientific, technical, and economic problem areas that could impede the rapid exploitation of these materials are identified. Recommendations are presented covering broad areas of research and development.

  5. Synthesis of mullite coatings by chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Mulpuri, R.P.; Auger, M.; Sarin, V.K. [Boston Univ., MA (United States)

    1996-08-01

    Formation of mullite on ceramic substrates via chemical vapor deposition was investigated. Mullite is a solid solution of Al{sub 2}O{sub 3} and SiO{sub 2} with a composition of 3Al{sub 2}O{sub 3}{circ}2SiO{sub 2}. Thermodynamic calculations performed on the AlCl{sub 3}-SiCl{sub 4}-CO{sub 2}-H{sub 2} system were used to construct equilibrium CVD phase diagrams. With the aid of these diagrams and consideration of kinetic rate limiting factors, initial process parameters were determined. Through process optimization, crystalline CVD mullite coatings have been successfully grown on SiC and Si{sub 3}N{sub 4} substrates. Results from the thermodynamic analysis, process optimization, and effect of various process parameters on deposition rate and coating morphology are discussed.

  6. Biomineralized diamond-like carbon films with incorporated titanium dioxide nanoparticles improved bioactivity properties and reduced biofilm formation.

    Science.gov (United States)

    Lopes, F S; Oliveira, J R; Milani, J; Oliveira, L D; Machado, J P B; Trava-Airoldi, V J; Lobo, A O; Marciano, F R

    2017-12-01

    Recently, the development of coatings to protect biomedical alloys from oxidation, passivation and to reduce the ability for a bacterial biofilm to form after implantation has emerged. Diamond-like carbon films are commonly used for implanted medical due to their physical and chemical characteristics, showing good interactions with the biological environment. However, these properties can be significantly improved when titanium dioxide nanoparticles are included, especially to enhance the bactericidal properties of the films. So far, the deposition of hydroxyapatite on the film surface has been studied in order to improve biocompatibility and bioactive behavior. Herein, we developed a new route to obtain a homogeneous and crystalline apatite coating on diamond-like carbon films grown on 304 biomedical stainless steel and evaluated its antibacterial effect. For this purpose, films containing two different concentrations of titanium dioxide (0.1 and 0.3g/L) were obtained by chemical vapor deposition. To obtain the apatite layer, the samples were soaked in simulated body fluid solution for up to 21days. The antibacterial activity of the films was evaluated by bacterial eradication tests using Staphylococcus aureus biofilm. Scanning electron microscopy, X-ray diffraction, Raman scattering spectroscopy, and goniometry showed that homogeneous, crystalline, and hydrophilic apatite films were formed independently of the titanium dioxide concentration. Interestingly, the diamond-like films containing titanium dioxide and hydroxyapatite reduced the biofilm formation compared to controls. A synergism between hydroxyapatite and titanium dioxide that provided an antimicrobial effect against opportunistic pathogens was clearly observed. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Design and investigation of properties of nanocrystalline diamond optical planar waveguides.

    Science.gov (United States)

    Prajzler, Vaclav; Varga, Marian; Nekvindova, Pavla; Remes, Zdenek; Kromka, Alexander

    2013-04-08

    Diamond thin films have remarkable properties comparable with natural diamond. Because of these properties it is a very promising material for many various applications (sensors, heat sink, optical mirrors, chemical and radiation wear, cold cathodes, tissue engineering, etc.) In this paper we report about design, deposition and measurement of properties of optical planar waveguides fabricated from nanocrystalline diamond thin films. The nanocrystalline diamond planar waveguide was deposited by microwave plasma enhanced chemical vapor deposition and the structure of the deposited film was studied by scanning electron microscopy and Raman spectroscopy. The design of the presented planar waveguides was realized on the bases of modified dispersion equation and was schemed for 632.8 nm, 964 nm, 1 310 nm and 1 550 nm wavelengths. Waveguiding properties were examined by prism coupling technique and it was found that the diamond based planar optical element guided one fundamental mode for all measured wavelengths. Values of the refractive indices of our NCD thin film measured at various wavelengths were almost the same as those of natural diamond.

  8. Influence of electrodes on the photon energy deposition in CVD-diamond dosimeters studied with the Monte Carlo code PENELOPE

    International Nuclear Information System (INIS)

    Gorka, B; Nilsson, B; Fernandez-Varea, J M; Svensson, R; Brahme, A

    2006-01-01

    A new dosimeter, based on chemical vapour deposited (CVD) diamond as the active detector material, is being developed for dosimetry in radiotherapeutic beams. CVD-diamond is a very interesting material, since its atomic composition is close to that of human tissue and in principle it can be designed to introduce negligible perturbations to the radiation field and the dose distribution in the phantom due to its small size. However, non-tissue-equivalent structural components, such as electrodes, wires and encapsulation, need to be carefully selected as they may induce severe fluence perturbation and angular dependence, resulting in erroneous dose readings. By introducing metallic electrodes on the diamond crystals, interface phenomena between high- and low-atomic-number materials are created. Depending on the direction of the radiation field, an increased or decreased detector signal may be obtained. The small dimensions of the CVD-diamond layer and electrodes (around 100 μm and smaller) imply a higher sensitivity to the lack of charged-particle equilibrium and may cause severe interface phenomena. In the present study, we investigate the variation of energy deposition in the diamond detector for different photon-beam qualities, electrode materials and geometric configurations using the Monte Carlo code PENELOPE. The prototype detector was produced from a 50 μm thick CVD-diamond layer with 0.2 μm thick silver electrodes on both sides. The mean absorbed dose to the detector's active volume was modified in the presence of the electrodes by 1.7%, 2.1%, 1.5%, 0.6% and 0.9% for 1.25 MeV monoenergetic photons, a complete (i.e. shielded) 60 Co photon source spectrum and 6, 18 and 50 MV bremsstrahlung spectra, respectively. The shift in mean absorbed dose increases with increasing atomic number and thickness of the electrodes, and diminishes with increasing thickness of the diamond layer. From a dosimetric point of view, graphite would be an almost perfect electrode

  9. Solution precursor plasma deposition of nanostructured ZnO coatings

    International Nuclear Information System (INIS)

    Tummala, Raghavender; Guduru, Ramesh K.; Mohanty, Pravansu S.

    2011-01-01

    Highlights: → The solution precursor route employed is an inexpensive process with capability to produce large scale coatings at fast rates on mass scale production. → It is highly capable of developing tailorable nanostructures. → This technique can be employed to spray the coatings on any kind of substrates including polymers. → The ZnO coatings developed via solution precursor plasma spray process have good electrical conductivity and reflectivity properties in spite of possessing large amount of particulate boundaries, porosity and nanostructured grains. -- Abstract: Zinc oxide (ZnO) is a wide band gap semiconducting material that has various applications including optical, electronic, biomedical and corrosion protection. It is usually synthesized via processing routes, such as vapor deposition techniques, sol-gel, spray pyrolysis and thermal spray of pre-synthesized ZnO powders. Cheaper and faster synthesis techniques are of technological importance due to increased demand in alternative energy applications. Here, we report synthesis of nanostructured ZnO coatings directly from a solution precursor in a single step using plasma spray technique. Nanostructured ZnO coatings were deposited from the solution precursor prepared using zinc acetate and water/isopropanol. An axial liquid atomizer was employed in a DC plasma spray torch to create fine droplets of precursor for faster thermal treatment in the plasma plume to form ZnO. Microstructures of coatings revealed ultrafine particulate agglomerates. X-ray diffraction confirmed polycrystalline nature and hexagonal Wurtzite crystal structure of the coatings. Transmission electron microscopy studies showed fine grains in the range of 10-40 nm. Observed optical transmittance (∼65-80%) and reflectivity (∼65-70%) in the visible spectrum, and electrical resistivity (48.5-50.1 mΩ cm) of ZnO coatings are attributed to ultrafine particulate morphology of the coatings.

  10. Solution precursor plasma deposition of nanostructured ZnO coatings

    Energy Technology Data Exchange (ETDEWEB)

    Tummala, Raghavender [Department of Mechanical Engineering, University of Michigan - Dearborn, MI 48128 (United States); Guduru, Ramesh K., E-mail: rkguduru@umich.edu [Department of Mechanical Engineering, University of Michigan - Dearborn, MI 48128 (United States); Mohanty, Pravansu S. [Department of Mechanical Engineering, University of Michigan - Dearborn, MI 48128 (United States)

    2011-08-15

    Highlights: {yields} The solution precursor route employed is an inexpensive process with capability to produce large scale coatings at fast rates on mass scale production. {yields} It is highly capable of developing tailorable nanostructures. {yields} This technique can be employed to spray the coatings on any kind of substrates including polymers. {yields} The ZnO coatings developed via solution precursor plasma spray process have good electrical conductivity and reflectivity properties in spite of possessing large amount of particulate boundaries, porosity and nanostructured grains. -- Abstract: Zinc oxide (ZnO) is a wide band gap semiconducting material that has various applications including optical, electronic, biomedical and corrosion protection. It is usually synthesized via processing routes, such as vapor deposition techniques, sol-gel, spray pyrolysis and thermal spray of pre-synthesized ZnO powders. Cheaper and faster synthesis techniques are of technological importance due to increased demand in alternative energy applications. Here, we report synthesis of nanostructured ZnO coatings directly from a solution precursor in a single step using plasma spray technique. Nanostructured ZnO coatings were deposited from the solution precursor prepared using zinc acetate and water/isopropanol. An axial liquid atomizer was employed in a DC plasma spray torch to create fine droplets of precursor for faster thermal treatment in the plasma plume to form ZnO. Microstructures of coatings revealed ultrafine particulate agglomerates. X-ray diffraction confirmed polycrystalline nature and hexagonal Wurtzite crystal structure of the coatings. Transmission electron microscopy studies showed fine grains in the range of 10-40 nm. Observed optical transmittance ({approx}65-80%) and reflectivity ({approx}65-70%) in the visible spectrum, and electrical resistivity (48.5-50.1 m{Omega} cm) of ZnO coatings are attributed to ultrafine particulate morphology of the coatings.

  11. Coating of ceramic powders by chemical vapor deposition techniques (CVD)

    International Nuclear Information System (INIS)

    Haubner, R.; Lux, B.

    1997-01-01

    New ceramic materials with selected advanced properties can be designed by coating of ceramic powders prior to sintering. By variation of the core and coating material a large number of various powders and ceramic materials can be produced. Powders which react with the binder phase during sintering can be coated with stable materials. Thermal expansion of the ceramic materials can be adjusted by varying the coating thickness (ratio core/layer). Electrical and wear resistant properties can be optimized for electrical contacts. A fluidized bed reactor will be designed which allow the deposition of various coatings on ceramic powders. (author)

  12. The microstructure, mechanical and friction properties of protective diamond like carbon films on magnesium alloy

    Science.gov (United States)

    Zou, Y. S.; Wu, Y. F.; Yang, H.; Cang, K.; Song, G. H.; Li, Z. X.; Zhou, K.

    2011-12-01

    Protective hard coatings deposited on magnesium alloys are believed to be effective for overcoming their poor wear properties. In this work, diamond-like carbon (DLC) films as hard protective films were deposited on AZ91 magnesium alloy by arc ion plating under negative pulse bias voltages ranging from 0 to -200 V. The microstructure, composition and mechanical properties of the DLC films were analyzed by scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and nanoindentation. The tribological behavior of uncoated and coated AZ91 magnesium alloy was investigated using a ball-on-disk tribotester. The results show that the negative pulse bias voltage used for film deposition has a significant effect on the sp3 carbon content and mechanical properties of the deposited DLC films. A maximum sp3 content of 33.3% was obtained at -100 V, resulting in a high hardness of 28.6 GPa and elastic modulus of 300.0 GPa. The DLC films showed very good adhesion to the AZ91 magnesium alloy with no observable cracks and delamination even during friction testing. Compared with the uncoated AZ91 magnesium alloy, the magnesium alloy coated with DLC films exhibits a low friction coefficient and a narrow, shallow wear track. The wear resistance and surface hardness of AZ91 magnesium alloy can be significantly improved by coating a layer of DLC protective film due to its high hardness and low friction coefficient.

  13. The microstructure, mechanical and friction properties of protective diamond like carbon films on magnesium alloy

    International Nuclear Information System (INIS)

    Zou, Y.S.; Wu, Y.F.; Yang, H.; Cang, K.; Song, G.H.; Li, Z.X.; Zhou, K.

    2011-01-01

    Protective hard coatings deposited on magnesium alloys are believed to be effective for overcoming their poor wear properties. In this work, diamond-like carbon (DLC) films as hard protective films were deposited on AZ91 magnesium alloy by arc ion plating under negative pulse bias voltages ranging from 0 to -200 V. The microstructure, composition and mechanical properties of the DLC films were analyzed by scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and nanoindentation. The tribological behavior of uncoated and coated AZ91 magnesium alloy was investigated using a ball-on-disk tribotester. The results show that the negative pulse bias voltage used for film deposition has a significant effect on the sp 3 carbon content and mechanical properties of the deposited DLC films. A maximum sp 3 content of 33.3% was obtained at -100 V, resulting in a high hardness of 28.6 GPa and elastic modulus of 300.0 GPa. The DLC films showed very good adhesion to the AZ91 magnesium alloy with no observable cracks and delamination even during friction testing. Compared with the uncoated AZ91 magnesium alloy, the magnesium alloy coated with DLC films exhibits a low friction coefficient and a narrow, shallow wear track. The wear resistance and surface hardness of AZ91 magnesium alloy can be significantly improved by coating a layer of DLC protective film due to its high hardness and low friction coefficient.

  14. The microstructure, mechanical and friction properties of protective diamond like carbon films on magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Y.S., E-mail: yshzou75@gmail.com [School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, 210094 (China); Wu, Y.F.; Yang, H.; Cang, K. [School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, 210094 (China); Song, G.H. [School of Materials Science and Engineering, Shenyang University of Technology, Shenyang, Liaoning, 110178 (China); Li, Z.X.; Zhou, K. [School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, 210094 (China)

    2011-12-01

    Protective hard coatings deposited on magnesium alloys are believed to be effective for overcoming their poor wear properties. In this work, diamond-like carbon (DLC) films as hard protective films were deposited on AZ91 magnesium alloy by arc ion plating under negative pulse bias voltages ranging from 0 to -200 V. The microstructure, composition and mechanical properties of the DLC films were analyzed by scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and nanoindentation. The tribological behavior of uncoated and coated AZ91 magnesium alloy was investigated using a ball-on-disk tribotester. The results show that the negative pulse bias voltage used for film deposition has a significant effect on the sp{sup 3} carbon content and mechanical properties of the deposited DLC films. A maximum sp{sup 3} content of 33.3% was obtained at -100 V, resulting in a high hardness of 28.6 GPa and elastic modulus of 300.0 GPa. The DLC films showed very good adhesion to the AZ91 magnesium alloy with no observable cracks and delamination even during friction testing. Compared with the uncoated AZ91 magnesium alloy, the magnesium alloy coated with DLC films exhibits a low friction coefficient and a narrow, shallow wear track. The wear resistance and surface hardness of AZ91 magnesium alloy can be significantly improved by coating a layer of DLC protective film due to its high hardness and low friction coefficient.

  15. Tungsten coatings electro-deposited on CFC substrates from oxide molten salt

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Ningbo; Zhang, Yingchun, E-mail: zycustb@163.com; Lang, Shaoting; Jiang, Fan; Wang, Lili

    2014-12-15

    Tungsten is considered as plasma facing material in fusion devices because of its high melting point, its good thermal conductivity, its low erosion rate and its benign neutron activation properties. On the other hand, carbon based materials like C/C fiber composites (CFC) have been used for plasma facing materials (PFMs) due to their high thermal shock resistance, light weight and high strength. Tungsten coatings on CFC substrates are used in the JET divertor in the frame of the JET ITER-like wall project, and have been prepared by plasma spray (PS) and other techniques. In this study, tungsten coatings were electro-deposited on CFC from Na{sub 2}WO{sub 4}–WO{sub 3} molten salt under various deposition parameters at 900 °C in air. In order to obtain tungsten coatings with excellent performance, the effects of pulse duration ratio and pulse current density on microstructures and crystal structures of tungsten coatings were investigated by X-ray diffraction (XRD, Rigaku Industrial Co., Ltd., D/MAX-RB) and a scanning electron microscope (SEM, JSM 6480LV). It is found that the pulsed duration ratio and pulse current density had a significant influence on tungsten nucleation and electro-crystallization phenomena. SEM observation revealed that intact, uniform and dense tungsten coatings formed on the CFC substrates. Both the average grain size and thickness of the coating increased with the pulsed current density. The XRD results showed that the coatings consisted of a single phase of tungsten with the body centered cubic (BCC) structure. The oxygen content of electro-deposited tungsten coatings was lower than 0.05%, and the micro-hardness was about 400 HV.

  16. Nanocomposite metal amorphous-carbon thin films deposited by hybrid PVD and PECVD technique.

    Science.gov (United States)

    Teixeira, V; Soares, P; Martins, A J; Carneiro, J; Cerqueira, F

    2009-07-01

    Carbon based films can combine the properties of solid lubricating graphite structure and hard diamond crystal structure, i.e., high hardness, chemical inertness, high thermal conductivity and optical transparency without the crystalline structure of diamond. Issues of fundamental importance associated with nanocarbon coatings are reducing stress, improving adhesion and compatibility with substrates. In this work new nanocomposite coatings with improved toughness based in nanocrystalline phases of metals and ceramics embedded in amorphous carbon matrix are being developed within the frame of a research project: nc-MeNxCy/a-C(Me) with Me = Mo, Si, Al, Ti, etc. Carbide forming metal/carbon (Me/C) composite films with Me = Mo, W or Ti possess appropriate properties to overcome the limitation of pure DLC films. These novel coating architectures will be adopted with the objective to decrease residual stress, improve adherence and fracture toughness, obtain low friction coefficient and high wear-resistance. Nanocomposite DLC's films were deposited by hybrid technique using a PVD-Physically Vapor Deposition (magnetron sputtering) and Plasma Enhanced Chemical Vapor Deposition (PECVD), by the use of CH4 gas. The parameters varied were: deposition time, substrate temperature (180 degrees C) and dopant (Si + Mo) of the amorphous carbon matrix. All the depositions were made on silicon wafers and steel substrates precoated with a silicon inter-layer. The characterisation of the film's physico-mechanical properties will be presented in order to understand the influence of the deposition parameters and metal content used within the a-C matrix in the thin film properties. Film microstructure and film hybridization state was characterized by Raman Spectroscopy. In order to characterize morphology SEM and AFM will be used. Film composition was measured by Energy-Dispersive X-ray analysis (EDS) and by X-ray photoelectron spectroscopy (XPS). The contact angle for the produced DLC's on

  17. RF magnetron-sputtered coatings deposited from biphasic calcium phosphate targets for biomedical implant applications

    Directory of Open Access Journals (Sweden)

    K.A. Prosolov

    2017-09-01

    Full Text Available Bioactive calcium phosphate coatings were deposited by radio-frequency magnetron sputtering from biphasic targets of hydroxyapatite and tricalcium phosphate, sintered at different mass % ratios. According to Raman scattering and X-ray diffraction data, the deposited hydroxyapatite coatings have a disordered structure. High-temperature treatment of the coatings in air leads to a transformation of the quasi-amorphous structure into a crystalline one. A correlation has been observed between the increase in the Ca content in the coatings and a subsequent decrease in Ca in the biphasic targets after a series of deposition processes. It was proposed that the addition of tricalcium phosphate to the targets would led to a finer coating's surface topography with the average size of 78 nm for the structural elements.

  18. Deposition and Characterization of TRISO Coating Layers

    International Nuclear Information System (INIS)

    Kim, D. K.; Choi, D. J.; Lee, H. K.; Kim, J. K.; Kim, J. H.; Chun, J. H.

    2007-03-01

    Zirconium carbide has been chosen and studied as an advanced material of silicon carbide. In order to collect data on the basic properties and characteristics of Zirconium carbide, studies have been conducted using various methods. As a result of chemically vapor deposed subliming zirconium tetrachloride(ZrCl4) and using methane(CH4) as a source in hydrogen atmosphere, graphite film is deposited.. Zirconium carbide was deposited on the sample where silicon carbide was deposited on a graphite substrate using Zirconium sponge as a Zirconium source. In terms of physical characteristics, the deposited Zirconium carbide showed higher strength, but slightly lower elastic modulus than silicon carbide. In order to evaluate the mechanical properties of a coating layer in pre-irradiation step, internal pressure induced method and direct strength measurement method is carried out. In the internal pressure induced method, in order to produce the requirement pressure, pressure media is used. In the direct strength measurement method, the indentation experiment that indent on a hemisphere shell with plate indenter is conducted. For this method, the finite element analysis is used and the analysis is verified by indentation experiments. To measure the strength of TRISO particle SiC coating, SiC hemisphere shell is performed through grinding and heat treatment. Through the finite element analysis, strength evaluation equation is suggested. Using suggested equation, Strength evaluation is performed and the strength value shows 1025MPa as a result of statistical analysis

  19. Deposition and Characterization of TRISO Coating Layers

    Energy Technology Data Exchange (ETDEWEB)

    Kim, D. K.; Choi, D. J.; Lee, H. K.; Kim, J. K.; Kim, J. H.; Chun, J. H. [KAIST, Daejeon (Korea, Republic of)

    2007-03-15

    Zirconium carbide has been chosen and studied as an advanced material of silicon carbide. In order to collect data on the basic properties and characteristics of Zirconium carbide, studies have been conducted using various methods. As a result of chemically vapor deposed subliming zirconium tetrachloride(ZrCl4) and using methane(CH4) as a source in hydrogen atmosphere, graphite film is deposited.. Zirconium carbide was deposited on the sample where silicon carbide was deposited on a graphite substrate using Zirconium sponge as a Zirconium source. In terms of physical characteristics, the deposited Zirconium carbide showed higher strength, but slightly lower elastic modulus than silicon carbide. In order to evaluate the mechanical properties of a coating layer in pre-irradiation step, internal pressure induced method and direct strength measurement method is carried out. In the internal pressure induced method, in order to produce the requirement pressure, pressure media is used. In the direct strength measurement method, the indentation experiment that indent on a hemisphere shell with plate indenter is conducted. For this method, the finite element analysis is used and the analysis is verified by indentation experiments. To measure the strength of TRISO particle SiC coating, SiC hemisphere shell is performed through grinding and heat treatment. Through the finite element analysis, strength evaluation equation is suggested. Using suggested equation, Strength evaluation is performed and the strength value shows 1025MPa as a result of statistical analysis.

  20. Chemical vapor deposited fiber coatings and chemical vapor infiltrated ceramic matrix composites

    Energy Technology Data Exchange (ETDEWEB)

    Kmetz, M.A.

    1992-01-01

    Conventional Chemical Vapor Deposition (CVD) and Organometallic Chemical Vapor Deposition (MOCVD) were employed to deposit a series of interfacial coatings on SiC and carbon yarn. Molybdenum, tungsten and chromium hexacarbonyls were utilized as precursors in a low temperature (350[degrees]C) MOCVD process to coat SiC yarn with Mo, W and Cr oxycarbides. Annealing studies performed on the MoOC and WOC coated SiC yarns in N[sub 2] to 1,000[degrees]C establish that further decomposition of the oxycarbides occurred, culminating in the formation of the metals. These metals were then found to react with Si to form Mo and W disilicide coatings. In the Cr system, heating in N[sub 2] above 800[degrees]C resulted in the formation of a mixture of carbides and oxides. Convention CVD was also employed to coat SiC and carbon yarn with C, Bn and a new interface designated BC (a carbon-boron alloy). The coated tows were then infiltrated with SiC, TiO[sub 2], SiO[sub 2] and B[sub 4]C by a chemical vapor infiltration process. The B-C coatings were found to provide advantageous interfacial properties over carbon and BN coatings in several different composite systems. The effectiveness of these different coatings to act as a chemically inert barrier layer and their relationship to the degree of interfacial debonding on the mechanical properties of the composites were examined. The effects of thermal stability and strength of the coated fibers and composites were also determined for several difference atmospheres. In addition, a new method for determining the tensile strength of the as-received and coated yarns was also developed. The coated fibers and composites were further characterized by AES, SEM, XPS, IR and X-ray diffraction analysis.