Barrier Coatings for Refractory Metals and Superalloys

International Nuclear Information System (INIS)

SM Sabol; BT Randall; JD Edington; CJ Larkin; BJ Close

2006-01-01

In the closed working fluid loop of the proposed Prometheus space nuclear power plant (SNPP), there is the potential for reaction of core and plant structural materials with gas phase impurities and gas phase transport of interstitial elements between superalloy and refractory metal alloy components during service. Primary concerns are surface oxidation, interstitial embrittlement of refractory metals and decarburization of superalloys. In parallel with kinetic investigations, this letter evaluates the ability of potential coatings to prevent or impede communication between reactor and plant components. Key coating requirements are identified and current technology coating materials are reviewed relative to these requirements. Candidate coatings are identified for future evaluation based on current knowledge of design parameters and anticipated environment. Coatings were identified for superalloys and refractory metals to provide diffusion barriers to interstitial transport and act as reactive barriers to potential oxidation. Due to their high stability at low oxygen potential, alumina formers are most promising for oxidation protection given the anticipated coolant gas chemistry. A sublayer of iridium is recommended to provide inherent diffusion resistance to interstitials. Based on specific base metal selection, a thin film substrate--coating interdiffusion barrier layer may be necessary to meet mission life

Numerical studies of film formation in context of steel coating

Science.gov (United States)

Aniszewski, Wojciech; Zaleski, Stephane; Popinet, Stephane

2017-11-01

In this work, we present a detailed example of numerical study of film formation in the context of metal coating. Liquid metal is drawn from a reservoir onto a retracting solid sheet, forming a coating film characterized by phenomena such as longitudinal thickness variation (in 3D) or waves akin to that predicted by Kapitza and Kapitza (visible in two dimensions as well). While the industry standard configuration for Zinc coating is marked by coexistence of medium Capillary number (Ca = 0.03) and film Reynolds number above 1000, we present also parametric studies in order to establish more clearly to what degree does the numerical method influence film regimes obtained in the target configuration. The simulations have been performed using Basilisk, a grid-adapting, strongly optimized code derived from Gerris . Mesh adaptation allows for arbitrary precision in relevant regions such as the contact line or the meniscus, while a coarse grid is applied elsewhere. This adaptation strategy, as the results indicate, is the only realistic approach for numerical method to cover the wide range of necessary scales from the predicted film thickness (hundreds of microns) to the domain size (meters).

Experimental evaluation of coating delamination in vinyl coated metal forming

International Nuclear Information System (INIS)

Son, Young Ki; Lee, Chan Joo; Kim, Byung Min; Lee, Jung Min; Byoen, Sang Doek; Lee, Soen Bong

2012-01-01

In this paper, a new evaluation and prediction method for coating delamination during sheet metal forming is presented. On the basis of the forming limit diagram (FLD), the current study evaluates the delamination of PET coating by using a cross cut specimen, dome test, and rectangular cup drawing test. Dome test specimens were subjected to biaxial, plane strain, and uniaxial deformation modes. Rectangular cup drawing test specimens were subjected to the deep drawing deformation mode, and compression deformation mode. A vinyl coated metal (VCM) sheet consists of three layers of polymer on the sheet metals: a protective film, a PET layer and a PVC layer. The areas with coating delamination were identified, and the results of the evaluation were plotted according to major and minor strain values, depicting coating delamination. The constructed delamination limit diagram (DLD) can be used to determine the forming limit of VCM during the complex press forming process. ARGUS (GOM) was employed to identify the strain value and deformation mode of the delaminated surface after the press forming. After identifying the areas of delamination, the DLD of the PET coating can be constructed in a format similar to that of the FLD. The forming limit of the VCM sheet can be evaluated using the superimposition of the delamination limit strain of the coating onto the FLD of VCM sheet. The experimental results showed that the proposed test method will support the sheet metal forming process design for VCM sheets. The assessment method presented in this study can be used to determine the delamination limit strain under plastic deformation of other polymer coated metals. The experimental results suggested that the proposed testing method is effective in evaluating delamination for specific applications

Experimental evaluation of coating delamination in vinyl coated metal forming

Energy Technology Data Exchange (ETDEWEB)

Son, Young Ki; Lee, Chan Joo; Kim, Byung Min [Pusan National Univ., Busan (Korea, Republic of); Lee, Jung Min [Korea Institute of Industrial Technology, Busan (Korea, Republic of); Byoen, Sang Doek [HA Digital Engineering Gr., Seongsan Gu (Korea, Republic of); Lee, Soen Bong [Keimyung Univ., Daegu (Korea, Republic of)

2012-10-15

In this paper, a new evaluation and prediction method for coating delamination during sheet metal forming is presented. On the basis of the forming limit diagram (FLD), the current study evaluates the delamination of PET coating by using a cross cut specimen, dome test, and rectangular cup drawing test. Dome test specimens were subjected to biaxial, plane strain, and uniaxial deformation modes. Rectangular cup drawing test specimens were subjected to the deep drawing deformation mode, and compression deformation mode. A vinyl coated metal (VCM) sheet consists of three layers of polymer on the sheet metals: a protective film, a PET layer and a PVC layer. The areas with coating delamination were identified, and the results of the evaluation were plotted according to major and minor strain values, depicting coating delamination. The constructed delamination limit diagram (DLD) can be used to determine the forming limit of VCM during the complex press forming process. ARGUS (GOM) was employed to identify the strain value and deformation mode of the delaminated surface after the press forming. After identifying the areas of delamination, the DLD of the PET coating can be constructed in a format similar to that of the FLD. The forming limit of the VCM sheet can be evaluated using the superimposition of the delamination limit strain of the coating onto the FLD of VCM sheet. The experimental results showed that the proposed test method will support the sheet metal forming process design for VCM sheets. The assessment method presented in this study can be used to determine the delamination limit strain under plastic deformation of other polymer coated metals. The experimental results suggested that the proposed testing method is effective in evaluating delamination for specific applications.

Application of a tablet film coating model to define a process-imposed transition boundary for robust film coating.

Science.gov (United States)

van den Ban, Sander; Pitt, Kendal G; Whiteman, Marshall

2018-02-01

A scientific understanding of interaction of product, film coat, film coating process, and equipment is important to enable design and operation of industrial scale pharmaceutical film coating processes that are robust and provide the level of control required to consistently deliver quality film coated product. Thermodynamic film coating conditions provided in the tablet film coating process impact film coat formation and subsequent product quality. A thermodynamic film coating model was used to evaluate film coating process performance over a wide range of film coating equipment from pilot to industrial scale (2.5-400 kg). An approximate process-imposed transition boundary, from operating in a dry to a wet environment, was derived, for relative humidity and exhaust temperature, and used to understand the impact of the film coating process on product formulation and process control requirements. This approximate transition boundary may aid in an enhanced understanding of risk to product quality, application of modern Quality by Design (QbD) based product development, technology transfer and scale-up, and support the science-based justification of critical process parameters (CPPs).

Thin film plasma coatings from dielectric free-flowing materials

International Nuclear Information System (INIS)

Timofeeva, L.A.; Katrich, S.A.; Solntsev, L.A.

1994-01-01

Fabrication of thin film plasma coatings from insulating free-flowing materials is considered. Molybdenum-tart ammonium coating of 3...5 μ thickness deposited on glassy carbon, aluminium, silicon, nickel, cast iron and steel substrates in 'Bulat-ZT' machine using insulating free-flowing materials cathod was found to form due to adsorption, absorption and dissuasion processes. The use of insulating free-flowing materials coatings allow to exclude pure metals cathods in plasma-plating process

Polyethylene oxide film coating enhances lithium cycling efficiency of an anode-free lithium-metal battery.

Science.gov (United States)

Assegie, Addisu Alemayehu; Cheng, Ju-Hsiang; Kuo, Li-Ming; Su, Wei-Nien; Hwang, Bing-Joe

2018-03-29

The practical implementation of an anode-free lithium-metal battery with promising high capacity is hampered by dendrite formation and low coulombic efficiency. Most notably, these challenges stem from non-uniform lithium plating and unstable SEI layer formation on the bare copper electrode. Herein, we revealed the homogeneous deposition of lithium and effective suppression of dendrite formation using a copper electrode coated with a polyethylene oxide (PEO) film in an electrolyte comprising 1 M LiTFSI, DME/DOL (1/1, v/v) and 2 wt% LiNO3. More importantly, the PEO film coating promoted the formation of a thin and robust SEI layer film by hosting lithium and regulating the inevitable reaction of lithium with the electrolyte. The modified electrode exhibited stable cycling of lithium with an average coulombic efficiency of ∼100% over 200 cycles and low voltage hysteresis (∼30 mV) at a current density of 0.5 mA cm-2. Moreover, we tested the anode-free battery experimentally by integrating it with an LiFePO4 cathode into a full-cell configuration (Cu@PEO/LiFePO4). The new cell demonstrated stable cycling with an average coulombic efficiency of 98.6% and capacity retention of 30% in the 200th cycle at a rate of 0.2C. These impressive enhancements in cycle life and capacity retention result from the synergy of the PEO film coating, high electrode-electrolyte interface compatibility, stable polar oligomer formation from the reduction of 1,3-dioxolane and the generation of SEI-stabilizing nitrite and nitride upon lithium nitrate reduction. Our result opens up a new route to realize anode-free batteries by modifying the copper anode with PEO to achieve ever more demanding yet safe interfacial chemistry and control of dendrite formation.

Fracture resistance of dental nickel-titanium rotary instruments with novel surface treatment: Thin film metallic glass coating.

Science.gov (United States)

Chi, Chih-Wen; Deng, Yu-Lun; Lee, Jyh-Wei; Lin, Chun-Pin

2017-05-01

Dental nickel-titanium (NiTi) rotary instruments are widely used in endodontic therapy because they are efficient with a higher success rate. However, an unpredictable fracture of instruments may happen due to the surface characteristics of imperfection (or irregularity). This study assessed whether a novel surface treatment could increase fatigue fracture resistance of dental NiTi rotary instruments. A 200- or 500-nm thick Ti-zirconium-boron (Ti-Zr-B) thin film metallic glass was deposited on ProTaper Universal F2 files using a physical vapor deposition process. The characteristics of coating were analyzed by scanning electron microscopy, transmission electron microscopy, and X-ray diffractometry. In cyclic fatigue tests, the files were performed in a simulated root canal (radius=5 mm, angulation=60°) under a rotating speed of 300rpm. The fatigue fractured cross sections of the files were analyzed with their fractographic performances through scanning electron microscopy images. The amorphous structure of the Ti-Zr-B coating was confirmed by transmission electron microscopy and X-ray diffractometry. The surface of treated files presented smooth morphologies without grinding irregularity. For the 200- and 500-nm surface treatment groups, the coated files exhibited higher resistance of cyclic fatigue than untreated files. In fractographic analysis, treated files showed significantly larger crack-initiation zone; however, no significant differences in the areas of fatigue propagation and catastrophic fracture were found compared to untreated files. The novel surface treatment of Ti-Zr-B thin film metallic glass on dental NiTi rotary files can effectively improve the fatigue fracture resistance by offering a smooth coated surface with amorphous microstructure. Copyright © 2016. Published by Elsevier B.V.

Improvement of corrosion resistance of transparent conductive multilayer coating consisting of silver layers and transparent metal oxide layers

International Nuclear Information System (INIS)

Koike, Katsuhiko; Yamazaki, Fumiharu; Okamura, Tomoyuki; Fukuda, Shin

2007-01-01

An optical filter for plasma display panel (PDP) requires an electromagnetic shield with very high ability. The authors investigated a transparent conductive multilayer coating consisting of silver (Ag) layers and transparent metal oxide layers. The durability of the multilayer sputter coating, including the silver layer, is very sensitive to the surrounding atmosphere. For example, after an exposure test they found discolored points on the multilayer sputter coatings, possibly caused by migration of silver atoms in the silver layers. In their investigation, they modified the top surface of the multilayer sputter coatings with transition metals to improve the corrosion resistance of the multilayer coating. Specifically, they deposited transition metals 0.5-2 nm thick on the top surface of the multilayer coatings by sputtering. They chose indium tin oxide (ITO) as the transparent metal oxide. They applied the multilayer sputter coatings of seven layers to a polyethylene terephthalate (PET) film substrate. A cross-sectional structure of the film with the multilayer coatings is PET film/ITO/Ag/ITO/Ag/ITO/Ag/ITO. They evaluated the corrosion resistance of the films by a salt-water immersion test. In the test, they immersed the film with multilayer coatings into salt water, and then evaluated the appearance, transmittance, and electrical resistance of the multilayer coatings. They investigated several transition metals as the modifying material, and found that titanium and tantalum drastically improved the resistance of the multilayer coatings to the salt-water exposure without a significant decline in transmittance. They also investigated the relation between elapsed time after deposition of the modifying materials and resistance to the salt water. Furthermore, they investigated the effects of a heat treatment and an oxide plasma treatment on resistance to the salt water

Use of 2-hydroxylhydrazine as a new modifier in dip-coating nickel films

International Nuclear Information System (INIS)

Syukri, R.; Ito, Yusuke; Ban, Takayuki; Ohya, Yutaka; Takahashi, Yasutaka

2002-01-01

A modified version of the dip-coating technique, which uses 2-hydroxylhydrazine as a mild reducing agent, was applied in the fabrication of nickel thin films. Nickel acetate was used as metal source. Metallic nickel thin films were formed on glass substrates by firing in the range of 400-600 deg. C under nitrogen atmosphere. The deposited layers were composed of cubic Ni crystallites. X-ray photoelectron spectroscopy analysis indicated almost uniformity in composition throughout the film thickness. The morphology of the films analyzed by scanning electron microscopy and atomic force microscopy revealed a very weak roughness after firing at 400 deg. C and the films turned out to be homogeneous. A thin film of approximately 19 nm in thickness exhibited a high resistivity of 86 μΩ cm. However, the resistivity was found to gradually decrease with increasing film thickness up to 110 nm by repeated dip-coating, reaching a minimum value of approximately 10 μΩ cm

Infiltration processing of metal matrix composites using coated ceramic particulates

Science.gov (United States)

Leon-Patino, Carlos Alberto

2001-07-01

A new process was developed to fabricate particulate metal matrix composites (MMCs). The process involves three steps: (1) modifying the particulate surface by metal coating, (2) forming a particulate porous compact; and (3) introducing metal into the channel network by vacuum infiltration. MMCs with different reinforcements, volume fractions, and sizes can be produced by this technique. Powders of alumina and silicon carbide were successfully coated with nickel and copper in preparation for infiltration with molten aluminum. Electroless Ni and Cu deposition was used since it enhances the wettability of the reinforcements for composite fabrication. While Cu deposits were polycrystalline, traces of phosphorous co-deposited from the electroless bath gave an amorphous Ni-P coating. The effect of metal coating on wetting behavior was evaluated at 800°C on plain and metal-coated ceramic plates using a sessile drop technique. The metallic films eliminated the non-wetting behavior of the uncoated ceramics, leading to equilibrium contact angles in the order of 12° and below 58° for Ni and Cu coated ceramics, respectively. The spreading data indicated that local diffusion at the triple junction was the governing mechanism of the wetting process. Precipitation of intermetallic phases in the drop/ceramic interface delayed the formation of Al4C3. Infiltration with molten Al showed that the coated-particulates are suitable as reinforcing materials for fabricating MMCs, giving porosity-free components with a homogeneously distributed reinforcing phase. The coating promoted easy metal flow through the preform, compared to the non-infiltration behavior of the uncoated counterparts. Liquid state diffusion kinetics due to temperature dependent viscosity forces controlled the infiltration process. Microstructural analysis indicated the formation of intermetallic phases such as CuAl 2, in the case of Cu coating, and Ni2Al3 and NiAl 3 when Ni-coated powders were infiltrated. The

Reduction of metallosis in hip implant using thin film coating

Science.gov (United States)

Rajeshshyam, R.; Chockalingam, K.; Gayathri, V.; Prakash, T.

2018-04-01

Hip implant finds its emerging attraction due to it continuous demand over the years. The hip implants (femoral head) and acetabulum cup) mainly fabricated by metals such as stainless steel, cobalt chrome and titanium alloys, other than that ceramics and polyethylene have been used. The metal-on-metal hip implant was found to be best implant material for most of the surgeons due to its high surface finish, low wear rate and low chance of dislocation from its position after implanting. Where in metal based hip implant shows less wear rate of 0.01mm3/year. Metal-on-metal implant finds its advantage over other materials both in its mechanical and physical stability against human load. In M-O-M Cobalt- chromium alloys induce metal allergy. The metal allergy (particulate debris) that is generated by wear, fretting, fragmentation and which is unavoidable when a prosthesis is implanted, can induce an inflammatory reaction in some circumstances. The objectives of this research to evaluate thin film coating with Nano particle additives to reduce the wear leads to regarding metal ion release. Experimental results reveals that thin film Sol-Gel coating with 4wt. % of specimen reduced the cobalt and chromium ion release and reduces the wear rate. Wear rate reduced by 98% for 4wt. % graphene in 20N and 95% for 4wt. % graphene in 10N.

Simple Methods for Production of Nanoscale Metal Oxide Films from Household Sources

Science.gov (United States)

Campbell, Dean J.; Baliss, Michelle S.; Hinman, Jordan J.; Ziegenhorn, John W.; Andrews, Mark J.; Stevenson, Keith J.

2013-01-01

Production of thin metal oxide films was recently explored as part of an outreach program with a goal of producing nanoscale structures with household items. Household items coated with various metals or titanium compounds can be heated to produce colorful films with nanoscale thicknesses. As part of a materials chemistry laboratory experiment…

Solar selective performance of metal nitride/oxynitride based magnetron sputtered thin film coatings: a comprehensive review

Science.gov (United States)

Ibrahim, Khalil; Taha, Hatem; Mahbubur Rahman, M.; Kabir, Humayun; Jiang, Zhong-Tao

2018-03-01

Since solar-thermal collectors are considered to be the most direct way of converting solar energy into usable forms, in the last few years growing attention has been paid to the development of transition metal nitride and metal oxynitride based thin film selective surfaces for solar-thermal collectors, in order to harvest more solar energy. A solar-thermal energy system, generally, shows very high solar absorption of incident solar radiation from the solar-thermal collectors in the visible range (0.3 to 2.5 μm) and extremely low thermal losses through emission (or high reflection) in the infrared region (≥2.5 μm). The efficiency of a solar-thermal energy conversion system can be improved by the use of solar selective surfaces consisting of novel metallic nanoparticles embedded in metal nitride/oxynitride systems. In order to enhance the effectiveness of solar-thermal devices, solar selective surfaces with high thermal stability are a prerequisite. Over the years, substantial efforts have been made in the field of solar selective surfaces to attain higher solar absorptance and lower thermal emittance in high temperature (above 400 °C) applications. In this article, we review the present state-of-the-art transition metal nitride and/or oxynitride based vacuum sputtered nanostructured thin film coatings, with respect to their optical and solar selective surface applications. We have also summarized the solar selectivity data from recently published investigations, including discussion on some potential applications for these materials.

A study of TiN-coated metal-on-polymer bearing materials for hip prosthesis

Science.gov (United States)

Lee, Sung Bai; Choi, Jin Young; Park, Won Woong; Jeon, Jun Hong; Won, Sung Ok; Byun, Ji Young; Lim, Sang Ho; Han, Seung Hee

2010-08-01

The TiN-coated metal-on-polymer hip prosthetic pair has the potential to reduce wear debris of UHMWPE (ultra-high molecular weight polyethylene) and to prevent metallic-ion-induced cytotoxicity. However, high quality and adherent film is a key to the clinical success of hip prostheses. In this study, titanium nitride (TiN) films were deposited on stainless steel using plasma immersion ion implantation & deposition (PIII&D) technique to create high-quality film and an adherent interface. The chemical state and composition were analyzed by X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and energy dispersive spectroscopy (EDS). The mechanical properties of the films were characterized using a micro-hardness tester and a pin-on-disk wear tester, and an x-ray diffractometer (XRD) was used for a crystallographic analysis. The PIII&D-treated TiN films showed a stoichiometric and (200) preferred orientation and micro-hardness up to 150 % higher than untreated film. A TiN-coated specimen using the PIII&D process also showed less UHMWPE wear compared to untreated specimens. The volumetric wear rate of UHMWPE could be reduced by as much as 42 % compared to when Co-Cr alloy was used. The results of this study show that advanced TiN-coating via the PIII&D process is a viable means of reducing UHMWPE wear in the metal-on-polymer bearing couple.

Biofouling of Cr-Nickel Spray Coated Films on Steel Surfaces

International Nuclear Information System (INIS)

Yoshida, Kento; Kanematsu, Hideyuki; Kuroda, Daisuke; Ikigai, Hajime; Kogo, Takeshi; Yokoyama, Seiji

2012-01-01

Nowadays, corrosion of metals brings us serious economic loss and it often reaches several percentage of GNP. Particularly the marine corrosion was serious and the counter measure was very hard to be established, since the number of factors is huge and complicated. One of the complicated factors in marine corrosion is biofouling. Biofouling was classified into two main categories, microfouling and macrofouling. The former is composed of biofilm formation mainly. Marine bacteria are attached to material surfaces, seeking for nutrition in oligotrophic environment and they excrete polysaccharide to form biofilm on metal surfaces. Then larger living matters are attached on the biofilms to develop biofouling on metal surfaces, which often lead loss and failures of metals in marine environments. From the viewpoint of corrosion protection and maintenance of marine structures, biofouling should be mitigated as much as possible. In this study, we applied spray coating to steels and investigated if chromium-nickel spray coating could mitigate the biofouling, being compared with the conventional aluminium-zinc spray coating in marine environments. The specimens used for this investigation are aluminium, zinc, aluminium-zinc, stacked chromium/nickel and those films were formed on carbon steel (JIS SS400). And the pores formed by spray coating were sealed by a commercial reagent for some specimens. All of those specimens were immersed into sea water located at Marina Kawage (854-3, Chisato, Tsu, Mie Prefecture) in Ise Bay for two weeks. The depth of the specimen was two meter from sea water surface and the distance was always kept constant, since they were suspended from the floating pier. The temperature in sea water changed from 10 to 15 degrees Celsius during the immersion test. The biofouling behavior was investigated by low vacuum SEM (Hitachi Miniscope TM1000) and X-ray fluorescent analysis. When the spray coated specimens with and without sealing agents were compared

Development of alloy-film coated dispenser cathode for terahertz vacuum electron devices application

International Nuclear Information System (INIS)

Barik, R.K.; Bera, A.; Raju, R.S.; Tanwar, A.K.; Baek, I.K.; Min, S.H.; Kwon, O.J.; Sattorov, M.A.; Lee, K.W.; Park, G.-S.

2013-01-01

High power terahertz vacuum electron devices demand high current density and uniform emission dispenser cathode. It was found that the coating of noble metals e.g., Os, Ir, and Re on the surface of tungsten dispenser cathodes enhances the emission capabilities and uniformity. Hence metal coated cathode might be the best candidate for terahertz devices applications. In this study, ternary-alloy-film cathode (2Os:2Re:1 W) and Os coated cathode have been developed and the results are presented. The cathodes made out of this alloy coating showed 1.5 times higher emission and 0.02 eV emission uniformity as compared to those of simply Os coated cathodes which can be used in terahertz devices application.

Development of alloy-film coated dispenser cathode for terahertz vacuum electron devices application

Energy Technology Data Exchange (ETDEWEB)

Barik, R. K.; Bera, A. [School of Electrical Engineering and Computer Science, Seoul National University, Seoul (Korea, Republic of); Raju, R. S. [Central Electronics Engineering Research Institute (CEERI), Rajasthan (India); Tanwar, A. K.; Baek, I. K.; Min, S. H.; Kwon, O. J.; Sattorov, M. A. [Department of Physics and Astronomy, Center for THz-Bio Application Systems, and Seoul-Teracom Inc., Seoul National University, Seoul (Korea, Republic of); Lee, K. W. [LIG Nex1, Seoul (Korea, Republic of); Park, G.-S., E-mail: gunsik@snu.ac.kr [School of Electrical Engineering and Computer Science, Seoul National University, Seoul (Korea, Republic of); Department of Physics and Astronomy, Center for THz-Bio Application Systems, and Seoul-Teracom Inc., Seoul National University, Seoul (Korea, Republic of); Advanced Institute of Convergence Technology, Suwon-si, Gyeonggi-do (Korea, Republic of)

2013-07-01

High power terahertz vacuum electron devices demand high current density and uniform emission dispenser cathode. It was found that the coating of noble metals e.g., Os, Ir, and Re on the surface of tungsten dispenser cathodes enhances the emission capabilities and uniformity. Hence metal coated cathode might be the best candidate for terahertz devices applications. In this study, ternary-alloy-film cathode (2Os:2Re:1 W) and Os coated cathode have been developed and the results are presented. The cathodes made out of this alloy coating showed 1.5 times higher emission and 0.02 eV emission uniformity as compared to those of simply Os coated cathodes which can be used in terahertz devices application.

Piezoelectric characterization of Pb(Zr,Ti)O3 thin films deposited on metal foil substrates by dip coating

Science.gov (United States)

Hida, Hirotaka; Hamamura, Tomohiro; Nishi, Takahito; Tan, Goon; Umegaki, Toshihito; Kanno, Isaku

2017-10-01

We fabricated the piezoelectric bimorphs composed of Pb(Zr,Ti)O3 (PZT) thin films on metal foil substrates. To efficiently inexpensively manufacture piezoelectric bimorphs with high flexibility, 1.2-µm-thick PZT thin films were directly deposited on both surfaces of 10- and 20-µm-thick bare stainless-steel (SS) foil substrates by dip coating with a sol-gel solution. We confirmed that the PZT thin films deposited on the SS foil substrates at 500 °C or above have polycrystalline perovskite structures and the measured relative dielectric constant and dielectric loss were 323-420 and 0.12-0.17, respectively. The PZT bimorphs were demonstrated by comparing the displacements of the cantilever specimens driven by single- and double-side PZT thin films on the SS foil substrates under the same applied voltage. We characterized the piezoelectric properties of the PZT bimorphs and the calculated their piezoelectric coefficient |e 31,f| to be 0.3-0.7 C/m2.

Electrodes synthesized from carbon nanostructures coated with a smooth and conformal metal adlayer

Science.gov (United States)

Adzic, Radoslav; Harris, Alexander

2014-04-15

High-surface-area carbon nanostructures coated with a smooth and conformal submonolayer-to-multilayer thin metal films and their method of manufacture are described. The preferred manufacturing process involves the initial oxidation of the carbon nanostructures followed by a surface preparation process involving immersion in a solution with the desired pH to create negative surface dipoles. The nanostructures are subsequently immersed in an alkaline solution containing a suitable quantity of non-noble metal ions which adsorb at surface reaction sites. The metal ions are then reduced via chemical or electrical means. The nanostructures are exposed to a solution containing a salt of one or more noble metals which replace adsorbed non-noble surface metal atoms by galvanic displacement. The process can be controlled and repeated to obtain a desired film coverage. The resulting coated nanostructures may be used, for example, as high-performance electrodes in supercapacitors, batteries, or other electric storage devices.

Tribological performance of Zinc soft metal coatings in solid lubrication

Science.gov (United States)

Regalla, Srinivasa Prakash; Krishnan Anirudh, V.; Reddy Narala, Suresh Kumar

2018-04-01

Solid lubrication by soft coatings is an important technique for superior tribological performance in machine contacts involving high pressures. Coating with soft materials ensures that the subsurface machine component wear decreases, ensuring longer life. Several soft metal coatings have been studied but zinc coatings have not been studied much. This paper essentially deals with the soft coating by zinc through electroplating on hard surfaces, which are subsequently tested in sliding experiments for tribological performance. The hardness and film thickness values have been found out, the coefficient of friction of the zinc coating has been tested using a pin on disc wear testing machine and the results of the same have been presented.

Thin film pc-Si by aluminium induced crystallization on metallic substrate

Directory of Open Access Journals (Sweden)

Cayron C.

2013-04-01

Full Text Available Thin film polycrystalline silicon (pc-Si on flexible metallic substrates is promising for low cost production of photovoltaic solar cells. One of the attractive methods to produce pc-Si solar cells consists in thickening a large-grained seed layer by epitaxy. In this work, the deposited seed layer is made by aluminium induced crystallization (AIC of an amorphous silicon (a-Si thin film on metallic substrates (Ni/Fe alloy initially coated with a tantalum nitride (TaN conductive diffusion barrier layer. Effect of the thermal budget on the AIC grown pc-Si seed layer was investigated in order to optimize the process (i.e. the quality of the pc-Si thin film. Structural and optical characterizations were carried out using optical microscopy, μ-Raman and Electron Backscatter Diffraction (EBSD. At optimal thermal annealing conditions, the continuous AIC grown pc-Si thin film showed an average grain size around 15 μm. The grains were preferably (001 oriented which is favorable for its epitaxial thickening. This work proves the feasibility of the AIC method to grow large grains pc-Si seed layer on TaN coated metal substrates. These results are, in terms of grains size, the finest obtained by AIC on metallic substrates.

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

Optical thin films and coatings from materials to applications

CERN Document Server

Flory, Francois

2013-01-01

Optical coatings, including mirrors, anti-reflection coatings, beam splitters, and filters, are an integral part of most modern optical systems. This book provides an overview of thin film materials, the properties, design and manufacture of optical coatings and their use across a variety of application areas.$bOptical coatings, including mirrors, anti-reflection coatings, beam splitters, and filters, are an integral part of most modern optical systems. Optical thin films and coatings provides an overview of thin film materials, the properties, design and manufacture of optical coatings and their use across a variety of application areas. Part one explores the design and manufacture of optical coatings. Part two highlights unconventional features of optical thin films including scattering properties of random structures in thin films, optical properties of thin film materials at short wavelengths, thermal properties and colour effects. Part three focusses on novel materials for optical thin films and coatings...

An investigation of material properties and tribological performance of magnetron sputtered thin film coatings

Science.gov (United States)

Singh, Harpal

This dissertation is divided into two categories based upon lubrication functionality and its application. The categories are: Dry film lubrication and Fluid film lubrication with thin film coatings. Thin film coatings examined in this work were deposited using closed field unbalanced magnetron sputtering and RF-DC coupled magnetron sputtering systems. In Dry/Solid film lubrication, the mechanical, structural and tribological properties of two Molybdenum disulphide (MoS2) based coatings are examined and evaluated. Among the two coatings, one coating is doped with Ti (Ti-MoS2) and the other is a combination of metal, lubricant and oxide (Sb2O3/Au - MoS2). These coatings are known to provide low friction in vacuum environments. The goal of this work was to evaluate friction and wear performance of MoS2 doped coatings in unidirectional and reciprocating sliding contact under different environmental conditions. Sliding contact results showed friction and wear dependence on temperature and humidity. The formation and removal of transfer films and the recrystallization and reorientation of basal layers on the steel counterface was observed as the mechanism for low friction. Structural analysis revealed a relationship between the microstructural properties and tribological performance. It was also observed that the addition of dopants (Ti, Au, Sb 2O3) improved the mechanical properties as compared to pure MoS2 coatings. Further, the rolling contact performance of the coatings was measured on a five ball on rod tribometer and a Thrust bearing tribometer under vacuum and air environments. The rolling contact experiments indicated that life of the rolling components depend on the amount of material present between the contacts. Fluid film lubrication with thin film coatings investigates the possibilities to improve the performance and durability of tribological components when oils and thin films are synergistically coupled. In this work, the ability of a Diamond Like Carbon

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.

Novel composite cBN-TiN coating deposition method: structure and performance in metal cutting

International Nuclear Information System (INIS)

Russell, W.C.; Malshe, A.P.; Yedave, S.N.; Brown, W.D.

2001-01-01

Cubic boron nitride coatings are under development for a variety of applications but stabilization of the pure cBN form and adhesion of films deposited by PVD and ion-based methods has been difficult. An alternative method for depositing a composite cBN-TiN film has been developed for wear related applications. The coating is deposited in a two-stage process utilizing ESC (electrostatic spray coating) and CVI (chemical vapor infiltration). Fully dense films of cBN particles evenly dispersed in a continuous TiN matrix have been developed. Testing in metal cutting has shown an increase in tool life (turning - 4340 steel) of three to seven times, depending of machining parameters, in comparison with CVD deposited TiN films. (author)

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

Evaporation-Driven Deposition of ITO Thin Films from Aqueous Solutions with Low-Speed Dip-Coating Technique.

Science.gov (United States)

Ito, Takashi; Uchiyama, Hiroaki; Kozuka, Hiromitsu

2017-05-30

We suggest a novel wet coating process for preparing indium tin oxide (ITO) films from simple solutions containing only metal salts and water via evaporation-driven film deposition during low-speed dip coating. Homogeneous ITO precursor films were deposited on silica glass substrates from the aqueous solutions containing In(NO 3 ) 3 ·3H 2 O and SnCl 4 ·5H 2 O by dip coating at substrate withdrawal speeds of 0.20-0.50 cm min -1 and then crystallized by the heat treatment at 500-800 °C for 10-60 min under N 2 gas flow of 0.5 L min -1 . The ITO films heated at 600 °C for 30 min had a high optical transparency in the visible range and a good electrical conductivity. Multiple-coating ITO films obtained with five-times dip coating exhibited the lowest sheet (ρ S ) and volume (ρ V ) resistivities of 188 Ω sq -1 and 4.23 × 10 -3 Ω cm, respectively.

13th International Conference on Films and Coatings

International Nuclear Information System (INIS)

2017-01-01

. Examples of the use of different ions for the nano-processing of coatings and surfaces of solids were shown. In the series of reports were presented the results of studies on the effect of layout schemes of technological installation on the structure parameters and mechanical properties of wear-resistant coatings. The physical aspects of the developed by the authors low temperature process of plasma hardening of the surface layer of geometrically-complex products, characterized by the low-energy plasma particles that interact with surface atoms according to the scheme of heterogeneous recombination were discussed. The possibility of application of film coatings rich with hydrogen for storage and desorption of hydrogen were analyzed. Was proposed a film hydrogen accumulator for use in the mobile objects on hydrogen fuel cells. Were discussed the method of its production and its application prospects. Possibilities of acquisition of the graphene materials during the decomposition of acetylene with the plasma torch with DC power up to 35 kW were shown. The influence of the coating material and the geometric shape of the reactor on the morphology of graphene were determined. Results were presented at the modeling and study of the processes of reactive ion-plasma etching. The results of stochastic modeling of the formation of the layered structure and the characteristics (microstructure, porosity, roughness) of the ceramic coatings from powders of corundum (α-Al 2 O 3 phase) under conditions typical for the atmospheric plasma spraying and also detonation and supersonic flame spraying were shown. Fundamentals of physico-chemical model of reactive sputtering of the hot metal target in nitrogen environment were stated. The system of equations describing the model was solved for spraying of titanium in nitrogen environment. The features of the numerical method in modeling of processes of thin films formation were discussed. Was demonstrated the procedure of application of

Gold nanoparticle plasmon resonance in near-field coupled Au NPs layer/Al film nanostructure: Dependence on metal film thickness

Science.gov (United States)

Yeshchenko, Oleg A.; Kozachenko, Viktor V.; Naumenko, Antonina P.; Berezovska, Nataliya I.; Kutsevol, Nataliya V.; Chumachenko, Vasyl A.; Haftel, Michael; Pinchuk, Anatoliy O.

2018-05-01

We study the effects of coupling between plasmonic metal nanoparticles and a thin metal film by using light extinction spectroscopy. A planar monolayer of gold nanoparticles located near an aluminum thin film (thicknesses within the range of 0-62 nm) was used to analyze the coupling between the monolayer and the thin metal film. SPR peak area increase for polymer coated Au NPs, non-monotonical behavior of the peak area for bare Au NPs, as well as red shift and broadening of SPR at the increase of the Al film thickness have been observed. These effects are rationalized as a result of coupling of the layer of Au NPs with Al film through the field of localized surface plasmons in Au NPs that causes the excitation of collective plasmonic gap mode in the nanostructure. An additional mechanism for bare Au NPs is the non-radiative damping of SPR that is caused by the electrical contact between metal NPs and film.

Resistivity behavior of optimized PbTiO3 thin films prepared by spin coating method

Science.gov (United States)

Nurbaya, Z.; Wahid, M. H.; Rozana, M. D.; Alrokayan, S. A. H.; Khan, H. A.; Rusop, M.

2018-05-01

Th is study presents the resistivity behavior of PbTiO3 thin films which were prepared towards metal-insulator-metal capacitor device fabrication. The PbTiO3 thin films were prepared through sol-gel spin coating method that involved various deposition parameters that is (1) different molar concentration of PbTiO3 solutions, (2) various additional PbAc-content in PbTiO3 solutions, and (3) various annealing temperature on PbTiO3 thin films. Hence, an electrical measurement of current versus voltage was done to determine the resistivity behavior of PbTiO3 thin films.

Characteristics of indirect laser-induced plasma from a thin film of oil on a metallic substrate

Science.gov (United States)

Xiu, Jun-Shan; Bai, Xue-Shi; Motto-Ros, Vincent; Yu, Jin

2015-04-01

Optical emissions from the major and trace elements embodied in a transparent gel prepared from cooking oil were detected after the gel was spread in a thin film on a metallic substrate. Such emissions are due to the indirect breakdown of the coating layer. The generated plasma, a mixture of substances from the substrate, the layer, and the ambient gas, was characterized using emission spectroscopy. The characteristics of the plasma formed on the metal with and without the coating layer were investigated. The results showed that Al emission induced from the aluminum substrates coated with oil films extends away from the target surface to ablate the oil film. This finally formed a bifurcating circulation of aluminum vapor against a spherical confinement wall in the front of the plume, which differed from the evolution of the plasma induced from the uncoated aluminum target. The strongest emissions of elements from the oil films can be observed at 2 mm above the target after a detection delay of 1.0 μs. A high temperature zone has been observed in the plasma after the delay of 1.0 μs for the plasma induced from the coated metal. This higher temperature determined in the plasma allows the consideration of the sensitive detection of trace elements in liquids, gels, biological samples, or thin films.

Ion beam assisted deposition of metal-coatings on beryllium

International Nuclear Information System (INIS)

Tashlykov, I.S.; Tul'ev, V.V.

2015-01-01

Thin films were applied on beryllium substrates on the basis of metals (Cr, Ti, Cu and W) with method of the ion-assisted deposition in vacuum. Me/Be structures were prepared using 20 kV ions irradiation during deposition on beryllium neutral fraction generated from vacuum arc plasma. Rutherford back scattering and computer simulation RUMP code were applied to investigate the composition of the modified beryllium surface. Researches showed that the superficial structure is formed on beryllium by thickness ~ 50-60 nm. The covering composition includes atoms of the deposited metal (0.5-3.3 at. %), atoms of technological impurity carbon (0.8-1.8 at. %) and oxygen (6.3-9.9 at. %), atoms of beryllium from the substrate. Ion assisted deposition of metals on beryllium substrate is accompanied by radiation enhanced diffusion of metals, oxygen atoms in the substrate, out diffusion of beryllium, carbon atoms in the deposited coating and sputtering film-forming ions assists. (authors)

Thin Film Energy Storage Device with Spray‐Coated Sliver Paste Current Collector

Directory of Open Access Journals (Sweden)

Seong Man Yoon

2017-12-01

Full Text Available This paper challenges the fabrication of a thin film energy storage device on a flexible polymer substrate specifically by replacing most commonly used metal foil current collectors with coated current collectors. Mass‐manufacturable spray‐coating technology enables the fabrication of two different half‐cell electric double layer capacitors (EDLC with a spray‐coated silver paste current collector and a Ni foil current collector. The larger specific capacitances of the half‐cell EDLC with the spray‐coated silver current collector are obtained as 103.86 F/g and 76.8 F/g for scan rates of 10 mV/s and 500 mV/s, respectively. Further, even though the half‐cell EDLC with the spray‐coated current collector is heavier than that with the Ni foil current collector, smaller Warburg impedance and contact resistance are characterized from Nyquist plots. For the applied voltages ranging from −0.5 V to 0.5 V, the spray‐coated thin film energy storage device exhibits a better performance.

Spray-coated ligand-free Cu2ZnSnS4 nanoparticle thin films

DEFF Research Database (Denmark)

Engberg, Sara Lena Josefin; Murthy, Swathi; Kofod, Guggi

We have fabricated Cu2ZnSnS4 (CZTS) thin films from spray-coating ligand-free nanoparticle inks. The as-synthesized CZTS nanoparticles were inherently ligand-free [1], which allows the use of polar solvents, such as water and ethanol. Another advantage of these particles is that user- and environ......We have fabricated Cu2ZnSnS4 (CZTS) thin films from spray-coating ligand-free nanoparticle inks. The as-synthesized CZTS nanoparticles were inherently ligand-free [1], which allows the use of polar solvents, such as water and ethanol. Another advantage of these particles is that user......- and environmentally-friendly alkali metal chloride salts can be directly dissolved in controllable amounts. The homogeneous distribution of alkali metals in the ink allows uniform grain growth within the deposited absorber layer as a result of liquid phase assisted sintering. We find that particularly beneficial...... as an unquantifiable amount of ZnS. A Sono-tek spray-coating system is used which utilizes ultrasonic atomization. We investigate the effect of different binders, ink concentration, and spray-coating conditions, i.e. spray power, flow rate from syringe pump, distance between spray nozzle and the substrate, and time...

Vacuum deposition of high quality metal films on porous substrates

International Nuclear Information System (INIS)

Barthell, B.L.; Duchane, D.V.

1982-01-01

A composite mandrel has been developed consisting of a core of low density polymethylpentene foam overcoated with a thin layer of film-forming polymer. The surface tension and viscosity of the coating solution are important parameters in obtaining a polymer film which forms a continuous, smooth skin over the core without penetrating into the foam matrix. Water soluble film formers with surface tensions in the range of 45 dyn/cm and minimum viscosities of a few hundred centipoises have been found most satisfactory for coating polymethylpentene foam. By means of this technique, continuous polymer fims with thicknesses of 10--20 μm have been formed on the surface of machined polymethylpentene foam blanks. Aluminum has been vacuum deposited onto these composite mandrels to produce metal films which appear smooth and generally defect free even at 10 000 times magnification

Spin coated versus dip coated electrochromic tungsten oxide films: Structure, morphology, optical and electrochemical properties

International Nuclear Information System (INIS)

Deepa, M.; Saxena, T.K.; Singh, D.P.; Sood, K.N.; Agnihotry, S.A.

2006-01-01

A sol-gel derived acetylated peroxotungstic acid sol encompassing 4 wt.% of oxalic acid dihydrate (OAD) has been employed for the deposition of tungsten oxide (WO 3 ) films by spin coating and dip coating techniques, in view of smart window applications. The morphological and structural evolution of the as-deposited spin and dip coated films as a function of annealing temperature (250 and 500 o C) has been examined and compared by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD). A conspicuous feature of the dip coated film (annealed at 250 o C) is that its electrochromic and electrochemical properties ameliorate with cycling without degradation in contrast to the spin coated film for which these properties deteriorate under repetitive cycling. A comparative study of spin and dip coated nanostructured thin films (annealed at 250 o C) revealed a superior performance for the cycled dip coated film in terms of higher transmission modulation and coloration efficiency in solar and photopic regions, faster switching speed, higher electrochemical activity as well as charge storage capacity. While the dip coated film could endure 2500 color-bleach cycles, the spin coated film could sustain only a 1000 cycles. The better cycling stability of the dip coated film which is a repercussion of a balance between optimal water content, porosity and grain size hints at its potential for electrochromic window applications

Controlled delamination of metal films by hydrogen loading

Energy Technology Data Exchange (ETDEWEB)

Nikitin, Eugen

2008-11-18

n this work we quantitatively determine the adhesion energy between metal films and their substrates. Therefore a new controlled buckling technique is established, applying the strong compressive in-plane stress that results in thin films clamped on rigid substrates during hydrogen loading. When the elastic energy stored in the H-loaded thin film exceeds the adhesion energy between film and substrate, delamination occurs. At the onset of delamination, a critical hydrogen concentration, a critical stress value and a critical bending of the substrate are present, which are quantitative measures for the adhesion energy and permit its calculation. As the critical values are determined at the onset of delamination, plastic deformation is negligible, which denies the quantitative determination of adhesion energies in conventional test setups. In multilayer-systems, adhesion energies between substrates and films that hardly absorb hydrogen can be measured by the controlled buckling technique, when the films of interest are coated with hydrogen absorbing films (active layer). The measurements are performed easily and can be repeated under the same test conditions, while variables such as the thickness of the coating materials or the boundary surface structure can be varied and optimized. In this work the adhesion energies of different materials on polycarbonate and niobium on sapphire are investigated. (orig.)

Application of hybrid organic/inorganic polymers as coatings on metallic substrates

Science.gov (United States)

Augustinho, T. R.; Motz, G.; Ihlow, S.; Machado, R. A. F.

2016-09-01

Acrylic polymers, particularly poly (methyl methacrylate) (PMMA), have certain specific properties, such as good film formation, transparency, and good mechanical properties, which have been widely used in paints, coatings and adhesives. However, the limited chemical and physical stability of these pure polymers limits their applications when exposed to hostile conditions, as in ship hulls, for example. A suitable way to enhance PMMA properties is the addition of silicon polymers with very good protective characteristics. In this study, a PMMA and HTT 1800 (commercial silazane) copolymer were applied on metallic substrate and compared to pure PMMA and HTT 1800. All the materials were applied as coatings. They were applied on stainless steel via dip-coating to investigate the coating properties. Thermal cycling was employed to analyze coating durability at high temperatures (50 °C to 600 °C). Optical microscopy (OM) and scanning electron microscopy (SEM) were used to characterize the coated surfaces, and the adhesion of pure PMMA, pure HTT 1800 and PMMA/HTT 1800 coatings on metallic substrate was investigated by Cross-Cut-Test (ASTM D 3359). The sessile drop method was used to determine the contact angle. PMMA coatings presented complete degradation from 250 °C, while hybrid coatings of PMMA and HTT 1800 have good protection until 400 °C. The adherence of the coating on metallic substrate showed improvement in all synthesized materials when compared to pure PMMA, obtaining the best adherence possible. The contact angle test showed that the hydrophobicity of the hybrid coatings is higher than that of the pure coatings.

Metallic coating of microspheres

International Nuclear Information System (INIS)

Meyer, S.F.

1980-01-01

Extremely smooth, uniform metal coatings of micrometer thicknesses on microscopic glass spheres (microspheres) are often needed as targets for inertial confinement fusion (ICF) experiments. The first part of this paper reviews those methods used successfully to provide metal coated microspheres for ICF targets, including magnetron sputtering, electro- and electroless plating, and chemical vapor pyrolysis. The second part of this paper discusses some of the critical aspects of magnetron sputter coating of microspheres, including substrate requirements, the sticking of microspheres during coating (preventing a uniform coating), and the difficulties in growing the desired dense, smooth, uniform microstructure on continuously moving spherical substrates

Electrochemical and dissolution studies on coated film and magnetite pellet in PDCA and NTA based formulations

International Nuclear Information System (INIS)

Srinivasan, M.P.; Sumathi, S.; Rangarajan, S.; Narasimhan, S.V.

2000-01-01

In water cooled nuclear reactors magnetite often exists as both mobile particulate protective film on the inner surface of the PHT system. To determine the mechanism and kinetics of dissolution from a film coated on carbon steel (CS) and magnetite pellet electrochemical measurements were carried out in 2,6-pyridine dicarboxylic acid (PDCA) and nitrilo-triacetic acid (NTA) based formulations containing ascorbic acid (AA) and citric acid (CA) at 28 degC and 60 degC. The solution redox potential arises based on the release of relative amounts of Fe 2+ and Fe 3+ . Complexation, adsorption and reduction affect the concentration of these species in solutions. On coated specimen, the pore size and rate of formation via auto reduction contribute to the observed potential. In PDCA based formulation higher percentage of magnetite dissolution with lower base metal corrosion was observed as compared to that in NTA based formulation. The base metal aided dissolution due to the pores and microcracks in the film (Auto reduction) was observed for coated film. The dominant role of surface adsorption characteristics of PDCA, AA and CA were evident in magnetite pellet dissolution studies. (author)

Cytocompatibility of Siloxane-Containing Vaterite/Poly(l-lactic acid) Composite Coatings on Metallic Magnesium.

Science.gov (United States)

Yamada, Shinya; Maeda, Hirotaka; Obata, Akiko; Lohbauer, Ulrich; Yamamoto, Akiko; Kasuga, Toshihiro

2013-12-12

Poly(l-lactic acid)-based films which include 60 wt % of vaterite (V) or siloxane-containing vaterite (SiV) were coated on a pure magnesium substrate, denoted by PLLA/V or PLLA/SiV, respectively, to suppress early corrosion and improve its cytocompatibility. Both coating films adhered to the Mg substrate with 2.3-2.8 MPa of tensile bonding strength. Soaking test for 7 days in α-modified minimum essential medium revealed that the morphological instability of the PLLA/V film caused a higher amount of Mg 2+ ion to be released from the coating sample. On the other hand, in the case of the coating with the PLLA/SiV film, no morphological change even after the soaking test was observed, owing to the suppression of the degradation rate. In cell culture tests, the proliferation of mouse osteoblast-like cell (MC3T3-E1) was significantly enhanced by both coatings, in comparison with the uncoated magnesium substrate. The cell morphology revealed that a few less-spread cells were observed on the PLLA/V film, while more elongated cells were done on the PLLA/SiV film. The cells on the PLLA/SiV film exhibited an extremely higher alkaline phosphatase activity after 21 days of incubation than that on the PLLA/V one. The PLLA/SiV film suppressed the early corrosion and enhanced cytocompatibility on metallic magnesium.

Cytocompatibility of Siloxane-Containing Vaterite/Poly(l-lactic acid Composite Coatings on Metallic Magnesium

Directory of Open Access Journals (Sweden)

Shinya Yamada

2013-12-01

Full Text Available Poly(l-lactic acid-based films which include 60 wt % of vaterite (V or siloxane-containing vaterite (SiV were coated on a pure magnesium substrate, denoted by PLLA/V or PLLA/SiV, respectively, to suppress early corrosion and improve its cytocompatibility. Both coating films adhered to the Mg substrate with 2.3–2.8 MPa of tensile bonding strength. Soaking test for 7 days in α-modified minimum essential medium revealed that the morphological instability of the PLLA/V film caused a higher amount of Mg2+ ion to be released from the coating sample. On the other hand, in the case of the coating with the PLLA/SiV film, no morphological change even after the soaking test was observed, owing to the suppression of the degradation rate. In cell culture tests, the proliferation of mouse osteoblast-like cell (MC3T3-E1 was significantly enhanced by both coatings, in comparison with the uncoated magnesium substrate. The cell morphology revealed that a few less-spread cells were observed on the PLLA/V film, while more elongated cells were done on the PLLA/SiV film. The cells on the PLLA/SiV film exhibited an extremely higher alkaline phosphatase activity after 21 days of incubation than that on the PLLA/V one. The PLLA/SiV film suppressed the early corrosion and enhanced cytocompatibility on metallic magnesium.

Verification of thickness and surface roughness of a thin film transparent coating

DEFF Research Database (Denmark)

Mohaghegh, Kamran; Hansen, Hans Nørgaard; Pranov, H.

2013-01-01

Thin film coatings are extremely interesting for industries, where there is a need to protect a highly accurate surface which has tight dimensional tolerances. The topic is important both in the production of new metallic tools and repair applications. In both applications it is vital to have...

Impact of silver metallization and electron irradiation on the mechanical deformation of polyimide films

Science.gov (United States)

Muradov, A. D.; Mukashev, K. M.; Yar-Mukhamedova, G. Sh.; Korobova, N. E.

2017-11-01

The impact of silver metallization and electron irradiation on the physical and mechanical properties of polyimide films has been studied. The metal that impregnated the structure of the polyimide substrate was 1-5 μm. The surface coatings contained 80-97% of the relative silver mirror in the visible and infrared regions. Irradiation was performed at the ELU-6 linear accelerator with an average beam electron energy of 2 MeV, an integral current of up to 1000 μA, a pulse repetition rate of 200 Hz, and a pulse duration of 5 μs. The absorbed dose in the samples was 10, 20, 30, and 40 MGy. The samples were deformed at room temperature under uniaxial tension on an Instron 5982 universal testing system. The structural changes in the composite materials that result from the impact of the physical factors were studied using an X-ray diffractometer DRON-2M in air at 293 K using Cu K α radiation (λαCu = 1.5418 Å). A substantial growth of mechanical characteristics resulting from the film metallization, as compared to the pure film, was observed. The growth of the ultimate strength by Δσ = 105 MPa and the plasticity by Δɛ = 75% is connected with the characteristics of the change of structure of the metallized films and the chemical etching conditions. The electron irradiation of the metallized polyimide film worsens its elastic and strength characteristics due to the formation of new phases in the form of silver oxide in the coating. The concentration of these phases increased with increasing dose, which was also the result of the violation of the ordered material structure, namely, the rupture of polyimide macromolecule bonds and the formation of new phases of silver in the coating. A mathematical model was obtained that predicts the elastic properties of silver metallized polyimide films. This model agrees with the experimental data.

Effect of Annealing Temperature and Spin Coating Speed on Mn-Doped ZnS Nanocrystals Thin Film by Spin Coating

Directory of Open Access Journals (Sweden)

Noor Azie Azura Mohd Arif

2017-01-01

Full Text Available ZnS:Mn nanocrystals thin film was fabricated at 300°C and 500°C via the spin coating method. Its sol-gel was spin coated for 20 s at 3000 rpm and 4000 rpm with metal tape being used to mold the shape of the thin film. A different combination of these parameters was used to investigate their influences on the fabrication of the film. Optical and structural characterizations have been performed. Optical characterization was analyzed using UV-visible spectroscopy and photoluminescence spectrophotometer while the structural and compositional analysis of films was measured via field emission scanning electron microscopy and energy dispersive X-ray. From UV-vis spectra, the wavelength of the ZnS:Mn was 250 nm and the band gap was within the range 4.43 eV–4.60 eV. In room temperature PL spectra, there were two emission peaks centered at 460 nm and 590 nm. Under higher annealing temperature and higher speed used in spin coating, an increase of 0.05 eV was observed. It was concluded that the spin coating process is able to synthesize high quality spherical ZnS:Mn nanocrystals. This conventional process can replace other high technology methods due to its synthesis cost.

Effects of annealing and plasma treatment on the electrical and optical properties of spin-coated ITZO films

Energy Technology Data Exchange (ETDEWEB)

Lee, Dong-min; Kim, Jae-Kwan [Department of Materials Science and Metallurgical Engineering, Sunchon National University, Sunchon, Chonnam 540-742 (Korea, Republic of); Hao, Jinchen; Kim, Han-Ki [Department of Advanced Materials Engineering for Information and Electronics, Kyung Hee University, Yongin-si, Gyeonggi-do 446-701 (Korea, Republic of); Yoon, Jae-Sik [Division of Materials Science, Korea Basic Science Institute, Daejeon 305-333 (Korea, Republic of); Lee, Ji-Myon, E-mail: jimlee@sunchon.ac.kr [Department of Printed Electronics Engineering, Sunchon National University, Sunchon, Chonnam 540-742 (Korea, Republic of)

2014-01-15

Highlights: • The resistivity of ITZO was enhanced by H{sub 2} gas plasma treatment. • The transmittance of H{sub 2} treated film was same as that of ref. after wet treatment. • The plasma process was carried out at room temperature. -- Abstract: This paper reports the effects on the optical and electrical properties of indium tin zinc oxide (ITZO) films by annealing and hydrogen plasma treatment. ITZO films were prepared by spin-coating using ITZO nanoink. The sheet resistance of the spin-coated ITZO was decreased to 155 Ω/square after annealing at 300 °C. Subsequent inductively-coupled hydrogen plasma decreased the sheet resistance of the ITZO film further to 88 Ω/square due to the formation of a high density of O–H bonds and oxygen vacancies leaving a metal cluster on the surface, which is comparable to that of solution-processed ITO films. Although the transmittance of the hydrogen plasma-treated sample was decreased considerable by the formation of metal clusters, the transmittance and optical band gap could be enhanced without a deteriorating the electrical properties by removing the metal clusters using a H{sub 2}SO{sub 4} solution.

Effect of sputtered lanthanum hexaboride film thickness on field emission from metallic knife edge cathodes

Science.gov (United States)

Kirley, M. P.; Novakovic, B.; Sule, N.; Weber, M. J.; Knezevic, I.; Booske, J. H.

2012-03-01

We report experiments and analysis of field emission from metallic knife-edge cathodes, which are sputter-coated with thin films of lanthanum hexaboride (LaB6), a low-work function material. The emission current is found to depend sensitively on the thickness of the LaB6 layer. We find that films thinner than 10 nm greatly enhance the emitted current. However, cathodes coated with a thicker layer of LaB6 are observed to emit less current than the uncoated metallic cathode. This result is unexpected due to the higher work function of the bare metal cathode. We show, based on numerical calculation of the electrostatic potential throughout the structure, that the external (LaB6/vacuum) barrier is reduced with respect to uncoated samples for both thin and thick coatings. However, this behavior is not exhibited at the internal (metal/LaB6) barrier. In thinly coated samples, electrons tunnel efficiently through both the internal and external barrier, resulting in current enhancement with respect to the uncoated case. In contrast, the thick internal barrier in thickly coated samples suppresses current below the value for uncoated samples in spite of the lowered external barrier. We argue that this coating thickness variation stems from a relatively low (no higher than 1018 cm-3) free carrier density in the sputtered polycrystalline LaB6.

Protection of uranium by metallic coatings

International Nuclear Information System (INIS)

Baque, P.; Koch, P.; Dominget, R.; Darras, R.

1968-01-01

A study is made of the possibilities of inhibiting or limiting, by means of protective metallic coatings, the oxidation of uranium by carbon dioxide at high temperature. In general, surface films containing intermetallic compounds or solid solutions of uranium with aluminium, zirconium, copper, niobium, nickel or chromium are formed, according to the techniques employed which are described here. The processes most to be recommended are those of direct diffusion starting from a thin sheet or tube, of vacuum deposition, or of immersion in a molten bath of suitable composition. The conditions for preparing these coatings have been optimized as a function of the protective effect obtained in carbon dioxide at 450 or at 500 C. Only the aluminium and zirconium based coatings are really satisfactory since they can lead to a reduction by a factor of 5 to 10 in the oxidation rate of uranium in the conditions considered; they make it possible in particular to avoid or to reduce to a very large extent the liberation of powdered oxide. Furthermore, the coatings produced generally give the uranium good protection against atmospheric corrosion. (author) [fr

Progress in coating and radiation curing of metal and plastic objects

International Nuclear Information System (INIS)

Mayenknecht, H.

1983-01-01

The manyfold problems with one or multi-layered coatings on metal and plastic surfaces as adhesion and coat compound are the reasons for a rather slow progress of industrial applications of both radiation curing technologies (UV and EBC). Important reasons for this seemed to result from the fact that the manyfold offers of radiation sources were not optimum adapted to the chemistry of the coating materials. It was pointed out that tensions due to film contraction during polymerization process are the main reasons for insufficient adhesion. This presentation is an attempt to clarify both points of view

Methods and means for coating paper by film coating

NARCIS (Netherlands)

van der Maarel, Marc; Ter Veer, Arend Berend Cornelis; Vrieling-Smit, Annet; Delnoye, Pierre

2015-01-01

This invention relates to the field of paper coating, more in particular to means and methods for providing paper with at least one layer of pigment using film coating to obtain a well printable surface. Provided is a method for preparing coated paper comprising the steps of: a) providing a

Monitoring tablet surface roughness during the film coating process

DEFF Research Database (Denmark)

Seitavuopio, Paulus; Heinämäki, Jyrki; Rantanen, Jukka

2006-01-01

The purpose of this study was to evaluate the change of surface roughness and the development of the film during the film coating process using laser profilometer roughness measurements, SEM imaging, and energy dispersive X-ray (EDX) analysis. Surface roughness and texture changes developing during...... the process of film coating tablets were studied by noncontact laser profilometry and scanning electron microscopy (SEM). An EDX analysis was used to monitor the magnesium stearate and titanium dioxide of the tablets. The tablet cores were film coated with aqueous hydroxypropyl methylcellulose, and the film...... coating was performed using an instrumented pilot-scale side-vented drum coater. The SEM images of the film-coated tablets showed that within the first 30 minutes, the surface of the tablet cores was completely covered with a thin film. The magnesium signal that was monitored by SEM-EDX disappeared after...

Enhancement of as-sputtered silver-tantalum oxide thin film coating on biomaterial stainless steel by surface thermal treatment

Science.gov (United States)

Alias, Rodianah; Mahmoodian, Reza; Shukor, Mohd Hamdi Abd; Yew, Been Seok; Muhamad, Martini

2018-04-01

Stainless steel 316L (SS316L) is extensively used as surgical/clinical tools due to its low carbon content and excellent mechanical characteristic. The fabrication of metal ceramic based on this metallic biomaterial favor its biofunctionality properties. However, instability phase of amorphous thin film lead to degradation, corrosion and oxidation. Thus, thin film coating requires elevated adhesion strength and higher surface hardness to meet clinical tools criteria. In this study, the SS316L was deposited with micron thickness of Ag-TaO thin film by using magnetron sputtering. The microstructure, elemental analysis and phase identification of Ag-TaO thin film were characterized by using FESEM, EDX and XRD, respectively; whereas the micro scratch test and micro hardness test were performed by using Micro Scratch Testing System and Vickers Micro Hardness Tester, respectively. It was found that the coating thin film's adhesion and hardness strength were improved from 672 to 2749 mN and 142 to 158 Hv respectively. It was found that the as-deposited surface were treated at 500 °C of temperatures with 2 °C/min ramping rate enhance 4.1 times of the adhesion strength value. Furthermore, FESEM characterization revealed coarsening structure of the thin film coating which can provide high durability service.

Analysis of Hard Thin Film Coating

Science.gov (United States)

Shen, Dashen

1998-01-01

MSFC is interested in developing hard thin film coating for bearings. The wearing of the bearing is an important problem for space flight engine. Hard thin film coating can drastically improve the surface of the bearing and improve the wear-endurance of the bearing. However, many fundamental problems in surface physics, plasma deposition, etc, need further research. The approach is using electron cyclotron resonance chemical vapor deposition (ECRCVD) to deposit hard thin film an stainless steel bearing. The thin films in consideration include SiC, SiN and other materials. An ECRCVD deposition system is being assembled at MSFC.

Molecular insights into shellac film coats from different aqueous shellac salt solutions and effect on disintegration of enteric-coated soft gelatin capsules.

Science.gov (United States)

Al-Gousous, J; Penning, M; Langguth, P

2015-04-30

The purpose of this investigation was to study the effect of using different salts of shellac on the disintegration properties of shellac-based enteric coatings. In the last two decades, shellac has been increasingly used as an aqueous solution for enteric coating purposes, with the ammonium salt being the form typically used. Little investigation has been performed on using other salts, and therefore, this was the focus of our work. Enteric coatings, based on different shellac salts (ammonium, sodium, potassium and composite ammonium-sodium), were applied onto soft gelatin capsules. Disintegration testing of the coated soft gelatin capsules showed that alkali metal salts promote faster disintegration than ammonium salts. In order to determine the causes behind these differences, the solubility, thermal and spectroscopic properties of films cast from the different salts were investigated. The results show that films cast from ammonium-based salts of shellac are, unlike those cast from alkali metal-based salts, water-insoluble. Spectroscopic evidence suggests that this might be due to partial salt dissociation resulting in loss of ammonium as ammonia and reduced degree of shellac ionization during drying. In addition, oxidation of shellac aldehyde groups of the ammonium-based shellac salts could also play a role. And possible higher extent of shellac hydrolysis during the preparation of alkali metal salts might also be a factor. Therefore, the nature of the shellac salt used in the preparation of shellac-based aqueous coating solutions is a significant formulation factor affecting product performance. Copyright © 2014 Elsevier B.V. All rights reserved.

Enhanced thermoelectric properties of metal film on bismuth telluride-based materials

International Nuclear Information System (INIS)

Chao, Wen Hsuan; Chen, Yi Ray; Tseng, Shih Chun; Yang, Ping Hsing; Wu, Ren Jye; Hwang, Jenn Yeu

2014-01-01

Diffusion barriers have a significant influence on the reliability and life time of thermoelectric modules. Although nickel is commonly used as a diffusion barrier in commercial thermoelectric modules, several studies have verified that Ni migrates to bismuth telluride-based material during high temperature cycles and causes a loss in efficacy. In this paper, the influence of metal layers coated to p-type and n-type Bi 2 Te 3 on the interface characterization and thermoelectric property is studied using a RF magnetron sputtering. The findings from this study demonstrate the structural and thermoelectric properties of p-type and n-type Bi 2 Te 3 coated with different metal layers. The crystalline phase and compositional change of the interface between the Bi 2 Te 3 materials and the metal layers were determined using an X-ray diffractometer and scanning electron microscopy with energy dispersive spectroscopy. Formation of NiTe was observed in the sample of Ni/p-type Bi 2 Te 3 based films post-annealed in an N 2 atmosphere at 200 °C. In contrast, no Co x Te y was formed in the sample of Co/p-type Bi 2 Te 3 based films post-annealed at 200 °C. For as-deposited Ni/p-type and n-type Bi 2 Te 3 based legs, the Ni slightly diffused into the Bi 2 Te 3 based legs. A similar phenomenon also occurred in the as-deposited Co/p-type and n-type Bi 2 Te 3 based legs. The Seebeck coefficients of the Co contacts on the Bi 2 Te 3 based material displayed better behavior than those of the Ni contacts on the Bi 2 Te 3 based legs. Thus Co could be a suitable diffusion barrier for bulk Bi 2 Te 3 based material. The observed effects on the thermoelectric and structural properties of metal/Bi 2 Te 3 based material are crucial for understanding the interface between the diffusion barrier and thermoelectric materials. - Highlights: • Interface characterization of metal coated to p-type and n-type Bi 2 Te 3 is studied. • We examined the phase transformation of metal/Bi 2 Te 3 based films

Graphene: corrosion-inhibiting coating.

Science.gov (United States)

Prasai, Dhiraj; Tuberquia, Juan Carlos; Harl, Robert R; Jennings, G Kane; Rogers, Bridget R; Bolotin, Kirill I

2012-02-28

We report the use of atomically thin layers of graphene as a protective coating that inhibits corrosion of underlying metals. Here, we employ electrochemical methods to study the corrosion inhibition of copper and nickel by either growing graphene on these metals, or by mechanically transferring multilayer graphene onto them. Cyclic voltammetry measurements reveal that the graphene coating effectively suppresses metal oxidation and oxygen reduction. Electrochemical impedance spectroscopy measurements suggest that while graphene itself is not damaged, the metal under it is corroded at cracks in the graphene film. Finally, we use Tafel analysis to quantify the corrosion rates of samples with and without graphene coatings. These results indicate that copper films coated with graphene grown via chemical vapor deposition are corroded 7 times slower in an aerated Na(2)SO(4) solution as compared to the corrosion rate of bare copper. Tafel analysis reveals that nickel with a multilayer graphene film grown on it corrodes 20 times slower while nickel surfaces coated with four layers of mechanically transferred graphene corrode 4 times slower than bare nickel. These findings establish graphene as the thinnest known corrosion-protecting coating.

Laser-fusion target fabrication: application of organic coatings to metallic and nonmetallic micropellets by the glow-discharge polymerization of p-xylene

International Nuclear Information System (INIS)

Simonsic, G.A.

1976-01-01

Laser-fusion targets require thin, uniform organic-film coatings. A coating technique involving glow-discharge polymerization is described for applying highly adherent, extremely uniform, thin films of a high-temperature polymer to a variety of microsubstrates. Polymeric coatings as thick as 10 μm have been successfully deposited on hollow, spherical, 40- to 250-μm-diam micropellets of glass, metal-coated glass, and nickel/manganese alloy. Experimental yields of coatings of a quality acceptable for laser-fusion targets are typically greater than 90 percent

Corrosion-resistant amorphous metallic films of Mo49Cr33B18 alloy

Science.gov (United States)

Ramesham, R.; Distefano, S.; Fitzgerald, D.; Thakoor, A. P.; Khanna, S. K.

1987-01-01

Corrosion-resistant amorphous metallic alloy films of Mo49Cr33B18 with a crystallization temperature of 590 C were deposited onto glass and quartz substrates by magnetron sputter-quench technique. The amorphous nature of the films was confirmed by their diffuse X-ray diffraction patterns. The deposited films are densely packed (zone T) and exhibit low stress and good adhesion to the substrate. Corrosion current of as-deposited coating of MoCrB amorphous metallic alloy is approximately three orders of magnitude less than the corrosion current of 304 stainless steel in 1N H2SO4 solution.

Quantitative Appearance Inspection for Film Coated Tablets.

Science.gov (United States)

Yoshino, Hiroyuki; Yamashita, Kazunari; Iwao, Yasunori; Noguchi, Shuji; Itai, Shigeru

2016-01-01

The decision criteria for the physical appearance of pharmaceutical products are subjective and qualitative means of evaluation that are based entirely on human interpretation. In this study, we have developed a comprehensive method for the quantitative analysis of the physical appearance of film coated tablets. Three different kinds of film coated tablets with considerable differences in their physical appearances were manufactured as models, and their surface roughness, contact angle, color measurements and physicochemical properties were investigated as potential characteristics for the quantitative analysis of their physical appearance. All of these characteristics were useful for the quantitative evaluation of the physical appearances of the tablets, and could potentially be used to establish decision criteria to assess the quality of tablets. In particular, the analysis of the surface roughness and film coating properties of the tablets by terahertz spectroscopy allowed for an effective evaluation of the tablets' properties. These results indicated the possibility of inspecting the appearance of tablets during the film coating process.

Sol gel coatings doped with Ce ions deposited on industrial applications metals

International Nuclear Information System (INIS)

Pepe, A; Aparicio, M; Duran, A; Cere, S

2004-01-01

Compounds that contain chromates as corrosion inhibitors are widely used. Since these compounds are highly toxic, enormous efforts are being made to replace them. The lanthanides, especially cerium, have the right properties for this substitution. Different substrates can be protected by a variety of coatings. The sol-gel derived films can be deposited on different metals or alloys to increase their resistance to corrosion or to modify their surface properties by doped with different substances that can increase their protective strength, by combining the barrier capacity of the hybrid coating with the inhibitory properties of the cerium. This work presents the conditions for obtaining soles doped with cerium III and IV salts at room temperature and humidity. The parameters are also described for obtaining coatings by free immersion-extraction of fissures and pores on metallic substrates (stainless steel AISI 304). The behavior with corrosion of the coated samples was characterized with electrochemical tests (CW)

Thin films by metal-organic precursor plasma spray

International Nuclear Information System (INIS)

Schulz, Douglas L.; Sailer, Robert A.; Payne, Scott; Leach, James; Molz, Ronald J.

2009-01-01

While most plasma spray routes to coatings utilize solids as the precursor feedstock, metal-organic precursor plasma spray (MOPPS) is an area that the authors have investigated recently as a novel route to thin film materials. Very thin films are possible via MOPPS and the technology offers the possibility of forming graded structures by metering the liquid feed. The current work employs metal-organic compounds that are liquids at standard temperature-pressure conditions. In addition, these complexes contain chemical functionality that allows straightforward thermolytic transformation to targeted phases of interest. Toward that end, aluminum 3,5-heptanedionate (Al(hd) 3 ), triethylsilane (HSi(C 2 H 5 ) 3 or HSiEt 3 ), and titanium tetrakisdiethylamide (Ti(N(C 2 H 5 ) 2 ) 4 or Ti(NEt 2 ) 4 ) were employed as precursors to aluminum oxide, silicon carbide, and titanium nitride, respectively. In all instances, the liquids contain metal-heteroatom bonds envisioned to provide atomic concentrations of the appropriate reagents at the film growth surface, thus promoting phase formation (e.g., Si-C bond in triethylsilane, Ti-N bond in titanium amide, etc.). Films were deposited using a Sulzer Metco TriplexPro-200 plasma spray system under various experimental conditions using design of experiment principles. Film compositions were analyzed by glazing incidence x-ray diffraction and elemental determination by x-ray spectroscopy. MOPPS films from HSiEt 3 showed the formation of SiC phase but Al(hd) 3 -derived films were amorphous. The Ti(NEt 2 ) 4 precursor gave MOPPS films that appear to consist of nanosized splats of TiOCN with spheres of TiO 2 anatase. While all films in this study suffered from poor adhesion, it is anticipated that the use of heated substrates will aid in the formation of dense, adherent films.

TiCx thin films coatings prepared by reactive sputtering

International Nuclear Information System (INIS)

Saoula, N.; Handa, K.; Kesri, R.

2004-01-01

Full text.Transition metal carbides and nitrides attract large technological interest due to their unique properties like high hardness and young modulus, high electric conductivity, a considerable high-temperature strength, high corrosion resistance and high melting or decomposition temperatures. They have been applied as coatings for tools because of their superior properties. these materials have such properties due to atomic bonding, which shows a mixed covalent, metallic and ionic character. Among these nitrides and carbides titanium carbide is a compound of particular importance. Titanium carbide combines the advantages of a high melting point (3140 celsius degree) and hardness (3000 Hv) with those of relative lightness (density 4.93 10 3 Kg m -3 ).It also exhibits high resistance to both corrosion and oxidation and a relatively low friction coefficient. Usually, TiC films are produced by deposition with plasma-enhanced CVD (PCVD), thermal chemical vapour deposition (CVD) or activated reactive evaporation methods. However, these methods require high temperature (>600 celsius degree) substrates to achieve the deposition, which sometimes causes thermal damage to the deposited films. At temperature above 550 celsius degree, thermal diffusion of materials not suitable may also occur. In addition, it has been reported that the maximum temperature which permits the appropriate coating of hardened steel tools is 500 celsius degree. Therefore, it is desirable to develop a deposition technique for TiC films using low-temperature substrates to avoid thermal damage. So, different physical vapour deposition (PVD) processes for deposition of TiC at relatively low temperatures have been used through the years. These processes are based on vaporisation of titanium in hydrocarbon atmosphere or on sputtering of solid TiC target or titanium target in hydrocarbon atmosphere. the most often-used hydrocarbon gases are methane, acetylene, ethene and ethane. In previous works, we

Imprinting of metal receptors into multilayer polyelectrolyte films: fabrication and applications in marine antifouling

NARCIS (Netherlands)

Puniredd, S.R.; Janczewski, D.; Go, D.P.; Zhu, X.; Guo, S.; Teo, S.L-M.; Lee, S.S.C.; Vancso, Gyula J.

2015-01-01

Polymeric films constructed using the layer-by-layer (LbL) fabrication process were employed as a platform for metal ion immobilization and applied as a marine antifouling coating. The novel Cu2+ ion imprinting process described is based on the use of metal ion templates and LbL multilayer covalent

Glow discharge optical emission spectroscopy for accurate and well resolved analysis of coatings and thin films

KAUST Repository

Wilke, Marcus; Teichert, Gerd; Gemma, Ryota; Pundt, Astrid; Kirchheim, Reiner; Romanus, Henry; Schaaf, Peter

2011-01-01

overview on new developments in instrument design for accurate and well resolved thin film analyses is presented. The article focuses on the analytical capabilities of glow discharge optical emission spectrometry in the analysis of metallic coatings

Films and edible coatings containing antioxidants - a review

Directory of Open Access Journals (Sweden)

Kaliana Sitonio Eça

2014-06-01

Full Text Available The incorporation of natural antioxidants into films and edible coatings can modify their structure, improving their functionality and applicability in foods, such as in fresh-cut fruits. This paper reviews the more recent literature on the incorporation of antioxidants from several sources into films and edible coatings, for application in fruits and vegetables. The use of synthetic antioxidants in foods has been avoided due to their possible toxic effects. Instead, a wide range of natural antioxidants (such as essential oils and plant extracts, as well as pure compounds, like ascorbic acid and α-tocopherol have been incorporated into edible films and coatings to improve their bioactive properties. Films and coatings containing added antioxidants help to preserve or enhance the sensory properties of foods and add value to the food products by increasing their shelf life.

FIB NANOPATTERNING OF METAL FILMS ON PMMA SUBSTRATES: NON-SPUTTERING MODE

DEFF Research Database (Denmark)

Tavares, Luciana; Adashkevich, Vadzim; Chiriaev, Serguei

polymer materials, which results in material shrinkage in the irradiated areas [2]. In this work, we demonstrate that this mechanism can be used for nanopatterning thin metal films deposited on PMMA resist spin-coated onto a silicon substrate. For this purpose, the samples were irradiated with He+ FIB...

Coating of metals

International Nuclear Information System (INIS)

Smith, F.

1978-01-01

A method is described for coating the surface of an article of Ti, Zr or Ta, or an alloy thereof, with a tinning metal or alloy, the article having a shape other than that of a sheet. The method comprises contacting the surface of the article at an elevated temperature with the molten tinning metal and moving an ultrasonically excited probe over the surface to be coated, the probe being in contact with the surface of the article and with the tinning metal. The tinning metal may be Sn or Zn or a binary alloy of Sn with Zn, Cd or Bi at a temperature of 300 0 to 450 0 C. The head of the probe may be shaped to conform with the surface of the article. The method may be used to form composite articles, and may be applied to a pre-tinned steel article. (U.K.)

Titanium-silicon films prepared by spin and dip-coating

International Nuclear Information System (INIS)

Nassar, Eduardo J.; Ciuffi, Katia J.; Goncalves, Rogeria R.; Messaddeq, Younes; Ribeiro, Sidney J.L.

2003-01-01

The conditions for the preparation of luminescent materials, consisting of Eu 3+ ions entrapped in a titanium matrix, in the form of a thin film, using the sol-gel process, are described. The films were obtained from sols prepared with TEOS and TEOT, in the presence of acetylacetone as the hydrolysis-retarding agent, using the dip-coating and spin-coating techniques. The influence of these techniques on the films based on titanium and silicon are presented. The Eu 3+ was used as a luminescent probe. The films have been characterized by luminescence, reflection and transmittance. The thickness of the films could be related to the preparation procedure. Transparent thin films have been prepared by dip-coating technique. (author)

POLYMER COMPOSITE FILMS WITH SIZE-SELECTED METAL NANOPARTICLES FABRICATED BY CLUSTER BEAM TECHNIQUE

DEFF Research Database (Denmark)

Ceynowa, F. A.; Chirumamilla, Manohar; Popok, Vladimir

2017-01-01

Formation of polymer films with size-selected silver and copper nanoparticles (NPs) is studied. Polymers are prepared by spin coating while NPs are fabricated and deposited utilizing a magnetron sputtering cluster apparatus. The particle embedding into the films is provided by thermal annealing...... after the deposition. The degree of immersion can be controlled by the annealing temperature and time. Together with control of cluster coverage the described approach represents an efficient method for the synthesis of thin polymer composite layers with either partially or fully embedded metal NPs....... Combining electron beam lithography, cluster beam deposition and thermal annealing allows to form ordered arrays of metal NPs on polymer films. Plasticity and flexibility of polymer host and specific properties added by coinage metal NPs open a way for different applications of such composite materials...

Simulation of the coating film appearance for spray application

OpenAIRE

Seeler, Fabian; Hager, Christian; Schneider, Matthias; Tiedje, Oliver

2015-01-01

The coating film topography depends on the substrate structure, the application parameters and the coating material’s levelling properties. Substrates consisting of several materials with different surface structures and differently inclined areas make a homogenous coating film structure difficult. By means of simulations, the paint film structure is intended to be controlled so that the theoretical optimum is reached and the experimental effort can be reduced. The focus is on spray applicati...

Functional doped metal oxide films. Zinc oxide (ZnO) as transparent conducting oxide (TCO) titanium dioxide (TiO{sub 2}) as thermographic phosphor and protective coating

Energy Technology Data Exchange (ETDEWEB)

Nebatti Ech-Chergui, Abdelkader

2011-07-29

spectra indicate that the red characteristic emission of TiO{sub 2}: Eu{sup 3+} due to electric dipole {sup 5}D{sub 0} {yields}{sup 7} F{sub 2} transition occurring after ultraviolet excitation is the strongest. The decay time of the phosphorescence after UV excitation with a Nd:YAG laser (355 nm, f=10Hz) is temperature dependent in the range from 200 C up to 400 C. Finally, it has been found that the lifetime show a significant dependency on europium concentration. The development of rutile phase of titanium dioxide films on stainless steel substrates as protective coatings were investigated. Generally the rutile phases of TiO{sub 2} thin films do not adhere well on stainless steel substrates. In order to improve the adhesion, stainless steel substrates were first coated with titanium films using cathodic vacuum arc deposition. Then these titanium coatings were partially transformed to the rutile phase of titanium dioxide by thermal oxidation. The presence of the rutile phase of titanium dioxide and metallic titanium were confirmed by XRD. Cavitation erosion was used for the first time to investigate the adhesion properties of these coatings. Cavitation erosion tests confirmed that rutile films with a Ti inter layer are well adherent to stainless steel substrates and protect the substrate from erosion. The total mass loss of the thermally oxidized samples of Ti coated stainless steel was found around 3.5 times lower than of the uncoated samples. (orig.)

Surface Modification of Solution-Processed ZrO2 Films through Double Coating for Pentacene Thin-Film Transistors

Science.gov (United States)

Kwon, Jin-Hyuk; Bae, Jin-Hyuk; Lee, Hyeonju; Park, Jaehoon

2018-03-01

We report the modification of surface properties of solution-processed zirconium oxide (ZrO2) dielectric films achieved by using double-coating process. It is proven that the surface properties of the ZrO2 film are modified through the double-coating process; the surface roughness decreases and the surface energy increases. The present surface modification of the ZrO2 film contributes to an increase in grain size of the pentacene film, thereby increasing the field-effect mobility and decreasing the threshold voltage of the pentacene thin-film transistors (TFTs) having the ZrO2 gate dielectric. Herein, the molecular orientation of pentacene film is also studied based on the results of contact angle and X-ray diffraction measurements. Pentacene molecules on the double-coated ZrO2 film are found to be more tilted than those on the single-coated ZrO2 film, which is attributed to the surface modification of the ZrO2 film. However, no significant differences are observed in insulating properties between the single-and the double-coated ZrO2 dielectric films. Consequently, the characteristic improvements of the pentacene TFTs with the double-coated ZrO2 gate dielectric film can be understood through the increase in pentacene grain size and the reduction in grain boundary density.

Zinc oxide nanoparticle-coated films: fabrication, characterization, and antibacterial properties

Energy Technology Data Exchange (ETDEWEB)

Jiang, Yunhong, E-mail: y.jiang@leeds.ac.uk [University of Leeds, Institute of Particle Science and Engineering (United Kingdom); O’Neill, Alex J. [University of Leeds, School of Molecular and Cellular Biology (United Kingdom); Ding, Yulong [University of Leeds, Institute of Particle Science and Engineering (United Kingdom)

2015-04-15

In this article, novel antibacterial PVC-based films coated with ZnO nanoparticles (NPs) were fabricated, characterized, and studied for their antibacterial properties. It was shown that the ZnO NPs were coated on the surface of the PVC films uniformly and that the coating process did not affect the size and shape of the NPs on the surface of PVC films. Films coated with concentrations of either 0.2 or 0.075 g/L of ZnO NPs exhibited antibacterial activity against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria, but exhibited no antifungal activity against Aspergillus flavus and Penicillium citrinum. Smaller particles (100 nm) exhibited more potent antibacterial activity than larger particles (1000 nm). All ZnO-coated films maintained antibacterial activity after 30 days in water.

Superhydrophobic ceramic coatings enabled by phase-separated nanostructured composite TiO2–Cu2O thin films

International Nuclear Information System (INIS)

Aytug, Tolga; Paranthaman, Parans M; Simpson, John T; Christen, David K; Bogorin, Daniela F; Mathis, John E

2014-01-01

By exploiting phase-separation in oxide materials, we present a simple and potentially low-cost approach to create exceptional superhydrophobicity in thin-film based coatings. By selecting the TiO 2 –Cu 2 O system and depositing through magnetron sputtering onto single crystal and metal templates, we demonstrate growth of nanostructured, chemically phase-segregated composite films. These coatings, after appropriate chemical surface modification, demonstrate a robust, non-wetting Cassie–Baxter state and yield an exceptional superhydrophobic performance, with water droplet contact angles reaching to ∼172° and sliding angles <1°. As an added benefit, despite the photo-active nature of TiO 2 , the chemically coated composite film surfaces display UV stability and retain superhydrophobic attributes even after exposure to UV (275 nm) radiation for an extended period of time. The present approach could benefit a variety of outdoor applications of superhydrophobic coatings, especially for those where exposure to extreme atmospheric conditions is required. (papers)

Development of a flexible nanocomposite TiO{sub 2} film as a protective coating for bioapplications of superelastic NiTi alloys

Energy Technology Data Exchange (ETDEWEB)

Aun, Diego Pinheiro, E-mail: diegoaun@yahoo.com.br [Department of Metallurgical and Materials Engineering, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, 30270-901 Belo Horizonte, MG (Brazil); Houmard, Manuel, E-mail: mhoumard@ufmg.br [Department of Materials and Construction Engineering, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, 30270-901 Belo Horizonte, MG (Brazil); Mermoux, Michel, E-mail: michel.mermoux@lepmi.grenoble-inp.fr [LEPMI, Grenoble INP, rue de la Piscine—BP75 38402, Saint Martin d' Hères (France); Latu-Romain, Laurence, E-mail: laurence.latu-romain@simap.grenoble-inp.fr [SIR Team, Science et Ingénierie des Matériaux et Procédés, Grenoble INP, 1130, rue de la Piscine—BP75 38402, Saint Martin d' Hères (France); Joud, Jean-Charles, E-mail: jean-charles.joud@grenoble-inp.fr [SIR Team, Science et Ingénierie des Matériaux et Procédés, Grenoble INP, 1130, rue de la Piscine—BP75 38402, Saint Martin d' Hères (France); Berthomé, Gregory, E-mail: gregory.berthome@simap.grenoble-inp.fr [SIR Team, Science et Ingénierie des Matériaux et Procédés, Grenoble INP, 1130, rue de la Piscine—BP75 38402, Saint Martin d' Hères (France); Buono, Vicente Tadeu Lopes, E-mail: vbuono@demet.ufmg.br [Department of Metallurgical and Materials Engineering, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, 30270-901 Belo Horizonte, MG (Brazil)

2016-07-01

Highlights: • A NiTi alloy was coated with a flexible TiO{sub 2} protective layer via the sol–gel method. • Maximum flexibility was obtained with a nanocomposite crystalline/amorphous film. • The film reduces the Ni surface content, possibly improving the biocompatibility. - Abstract: An experimental procedure to coat superelastic NiTi alloys with flexible TiO{sub 2} protective nanocomposite films using sol–gel technology was developed in this work to improve the metal biocompatibility without deteriorating its superelastic mechanical properties. The coatings were characterized by scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and glazing incidence X-ray diffraction. The elasticity of the film was tested in coated specimens submitted to three-point bending tests. A short densification by thermal treatment at 500 °C for 10 min yielded a bilayer film consisting of a 50 nm-thick crystallized TiO{sub 2} at the inner interface with another 50-nm-thick amorphous oxide film at the outer interface. This bilayer could sustain over 6.4% strain without cracking and could thus be used to coat biomedical instruments as well as other devices made with superelastic NiTi alloys.

Preparation of chitosan-coated polyethylene packaging films by DBD plasma treatment.

Science.gov (United States)

Theapsak, Siriporn; Watthanaphanit, Anyarat; Rujiravanit, Ratana

2012-05-01

Polyethylene (PE) packaging films were coated with chitosan in order to introduce the antibacterial activity to the films. To augment the interaction between the two polymers, we modified the surfaces of the PE films by dielectric barrier discharge (DBD) plasma before chitosan coating. After that the plasma-treated PE films were immersed in chitosan acetate solutions with different concentrations of chitosan. The optimum plasma treatment time was 10 s as determined from contact angle measurement. Effect of the plasma treatment on the surface roughness of the PE films was investigated by atomic force microscope (AFM) while the occurrence of polar functional groups was observed by X-ray photoelectron spectroscope (XPS) and Fourier transformed infrared spectroscope (FTIR). It was found that the surface roughness as well as the occurrence of oxygen-containing functional groups (i.e., C═O, C-O, and -OH) of the plasma-treated PE films increased from those of the untreated one, indicating that the DBD plasma enhanced hydrophilicity of the PE films. The amounts of chitosan coated on the PE films were determined after washing the coated films in water for several number of washing cycles prior to detection of the chitosan content by the Kjaldahl method. The amounts of chitosan coated on the PE films were constant after washing for three times and the chitosan-coated PE films exhibited appreciable antibacterial activity against Escherichia coli and Staphylococcus aureus. Hence, the obtained chitosan-coated PE films could be a promising candidate for antibacterial food packaging.

Bare and protected sputtered-noble-metal films for surface-enhanced Raman spectroscopy

Science.gov (United States)

Talaga, David; Bonhommeau, Sébastien

2014-11-01

Sputtered silver and gold films with different surface morphologies have been prepared and coated with a benzenethiol self-assembled monolayer. Rough noble metal films showed strong Raman features assigned to adsorbed benzenethiol molecules upon irradiation over a wide energy range in the visible spectrum, which disclosed the occurrence of a significant surface-enhanced Raman scattering with maximal enhancement factors as high as 6 × 106. In addition, the adsorption of ethanethiol onto silver surfaces hinders their corrosion over days while preserving mostly intact enhancement properties of naked silver. This study may be applied to develop stable and efficient metalized probes for tip-enhanced Raman spectroscopy.

Refractive-index change caused by electrons in amorphous AsS and AsSe thin films doped with different metals by photodiffusion

International Nuclear Information System (INIS)

Nordman, Olli; Nordman, Nina; Pashkevich, Valfrid

2001-01-01

The refractive-index change caused by electrons was measured in amorphous AsS and AsSe thin films. Films were coated with different metals. Diffraction gratings were written by electron-beam lithography. The interactions of electrons in films with and without the photodiffusion of overcoated metal were compared. Incoming electrons caused metal atom and ion diffusion in both investigated cases. The metal diffusion was dependent on the metal and it was found to influence the refractive index. In some cases lateral diffusion of the metal was noticed. The conditions for applications were verified. Copyright 2001 Optical Society of America

Sulfonated Polyaniline Coated Mercury Film Electrodes for Voltammetric Analysis of Metals in Water

Directory of Open Access Journals (Sweden)

Denise Alves Fungaro

2001-11-01

Full Text Available The electrochemical polymerization of 2-aminobenzenesulfonic acid with and without aniline has been carried by cyclic potencial sweep in sulfuric acid solution at the glassy carbon electrode. The polymer and copolymer formed have been characterized voltammetrically. The sulfonated polyaniline coated mercury thin-film electrodes have been evaluated for use with anodic stripping voltammetry. The electrodes were tested and compared with a conventional thin-film mercury electrode. Calibration plots showed linearity up to 10-7 mol L-1. Detection limits for zinc, lead and cadmium test species are very similar at around 12 nmol L-1. Applications to analysis of waters samples are demonstrated.

Deposition and Characterization of Thin Films on Metallic Substrates

Science.gov (United States)

Gatica, Jorge E.

2005-01-01

A CVD method was successfully developed to produce conversion coatings on aluminum alloys surfaces with reproducible results with a variety of precursors. A well defined protocol to prepare the precursor solutions formulated in a previous research was extended to other additives. It was demonstrated that solutions prepared following such a protocol could be used to systematically generate protective coatings onto aluminum surfaces. Experiments with a variety of formulations revealed that a refined deposition protocol yields reproducible conversion coatings of controlled composition. A preliminary correlation between solution formulations and successful precursors was derived. Coatings were tested for adhesion properties enhancement for commercial paints. A standard testing method was followed and clear trends were identified. Only one precursors was tested systematically. Anticipated work on other precursors should allow a better characterization of the effect of intermetallics on the production of conversion/protective coatings on metals and ceramics. The significance of this work was the practical demonstration that chemical vapor deposition (CVD) techniques can be used to systematically generate protective/conversion coating on non-ferrous surfaces. In order to become an effective approach to replace chromate-based pre- treatment processes, namely in the aerospace or automobile industry, the process parameters must be defined more precisely. Moreover, the feasibility of scale-up designs necessitates a more comprehensive characterization of the fluid flow, transport phenomena, and chemical kinetics interacting in the process. Kinetic characterization showed a significantly different effect of magnesium-based precursors when compared to iron-based precursors. Future work will concentrate on refining the process through computer simulations and further experimental studies on the effect of other transition metals to induce deposition of conversion/protective films

ANTIREFLECTION MULTILAYER COATINGS WITH THIN METAL LAYERS

Directory of Open Access Journals (Sweden)

L. A. Gubanova

2016-03-01

Full Text Available The design of anti-reflective coatings for metal surfaces of Al, Ti, N,i Cr is proposed. The coatings have the form of alternating layers of dielectric/metal/dielectric with the number of cells up to15. The method of calculation of such coatings is proposed. We have calculated the coatings of the type [HfO2/Cr/HfO2]15, [ZrO2/Ti/Al2O3]15, [ZrO2/Cr/ZrO2]15. It is shown that the proposed interference coatings provide reduction of the residual reflectance of the metal several times (from 3.5 to 6.0 in a wide spectral range (300-1000 nm. The proposed coatings can be recommended as anti-reflective coatings for energy saving solar systems and batteries, and photovoltaic cells.

Tantalum oxide thin films as protective coatings for sensors

DEFF Research Database (Denmark)

Christensen, Carsten; Reus, Roger De; Bouwstra, Siebe

1999-01-01

Reactively sputtered tantalum oxide thin films have been investigated as protective coatings for aggressive media exposed sensors. Tantalum oxide is shown to be chemically very robust. The etch rate in aqueous potassium hydroxide with pH 11 at 140°C is lower than 0.008 Å h-l. Etching in liquids...... with pH values in the range from pH 2 to 11 have generally given etch rates below 0.04 Å h-l. On the other hand patterning is possible in hydrofluoric acid. Further, the passivation behaviour of amorphous tantalum oxide and polycrystalline Ta2O5 is different in buffered hydrofluoric acid. By ex situ...... annealing O2 in the residual thin-film stress can be altered from compressive to tensile and annealing at 450°C for 30 minutes gives a stress-free film. The step coverage of the sputter deposited amorphous tantalum oxide is reasonable, but metallization lines are hard to cover. Sputtered tantalum oxide...

The resistance changes of carbon and metal oxide film resistors by irradiation of 60Co γ rays

International Nuclear Information System (INIS)

Okamoto, Shinichi; Fujino, Takahiro; Furuta, Junichiro; Yoshida, Toshio

1979-01-01

The resistance changes of glass-sealed deposited-carbon-film and carbon-coated-film resitors and metal oxide glazed resistors made in USA were studied by gamma-ray irradiation. (1) The resistances of deposited-carbon-film resistors of 50, 100 and 200 megohm did not change by irradiation of gamma rays up to 1.9 x 10 9 R. (2) The carbon-coated-film resistors of 100, 1000, 10000 and 100000 megohm had negative resistance changes by irradiation of gamma rays up to 9.9 x 10 8 R. (3) The resistances of metal oxide glazed resistors of 100, 1000 and 10000 megohm did not change by irradiation of gamma rays up to 8.8 x 10 8 R. When radiation monitoring instruments with hi-meg resistors are used in a gamma field with high intensity, the resistors must not be exposed to gamma rays with high doses, or the resistors which do not change by gamma-ray irradiation must be selected. (author)

Metallic and Ceramic Thin Film Thermocouples for Gas Turbine Engines

Directory of Open Access Journals (Sweden)

Otto J. Gregory

2013-11-01

Full Text Available Temperatures of hot section components in today’s gas turbine engines reach as high as 1,500 °C, making in situ monitoring of the severe temperature gradients within the engine rather difficult. Therefore, there is a need to develop instrumentation (i.e., thermocouples and strain gauges for these turbine engines that can survive these harsh environments. Refractory metal and ceramic thin film thermocouples are well suited for this task since they have excellent chemical and electrical stability at high temperatures in oxidizing atmospheres, they are compatible with thermal barrier coatings commonly employed in today’s engines, they have greater sensitivity than conventional wire thermocouples, and they are non-invasive to combustion aerodynamics in the engine. Thin film thermocouples based on platinum:palladium and indium oxynitride:indium tin oxynitride as well as their oxide counterparts have been developed for this purpose and have proven to be more stable than conventional type-S and type-K thin film thermocouples. The metallic and ceramic thin film thermocouples described within this paper exhibited remarkable stability and drift rates similar to bulk (wire thermocouples.

Polyester fabric coated with Ag/ZnO composite film by magnetron sputtering

Energy Technology Data Exchange (ETDEWEB)

Yuan, Xiaohong, E-mail: yxhong1981_2004@126.com [Key Laboratory of Eco-Textiles, Ministry of Education, Jiangnan University, Wuxi 214122, Jiangsu (China); Faculty of Clothing and Design, Minjiang University, Fuzhou 350121, Fujian (China); Xu, Wenzheng, E-mail: xwz8199@126.com [Key Laboratory of Eco-Textiles, Ministry of Education, Jiangnan University, Wuxi 214122, Jiangsu (China); Huang, Fenglin, E-mail: windhuang325@163.com [Key Laboratory of Eco-Textiles, Ministry of Education, Jiangnan University, Wuxi 214122, Jiangsu (China); Chen, Dongsheng, E-mail: mjuchen@126.com [Faculty of Clothing and Design, Minjiang University, Fuzhou 350121, Fujian (China); Wei, Qufu, E-mail: qfwei@jiangnan.edu.cn [Key Laboratory of Eco-Textiles, Ministry of Education, Jiangnan University, Wuxi 214122, Jiangsu (China)

2016-12-30

Highlights: • Ag/ZnO composite film was successfully deposited on polyester fabric by magnetron sputtering technique. • Ag film was easily oxidized into Ag{sub 2}O film in high vacuum oxygen environment. • The zinc film coated on the surface of Ag film before RF reactive sputtering could protect the silver film from oxidation. • Polyester fabric coated with Ag/ZnO composite film can obtained structural color. • The anti-ultraviolet and antistatic properties of polyester fabric coated with Ag/ZnO composite film all were good. - Abstract: Ag/ZnO composite film was successfully deposited on polyester fabric by using direct current (DC) magnetron sputtering and radio frequency (RF) magnetron reaction sputtering techniques with pure silver (Ag) and zinc (Zn) targets. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were used to examine the deposited film on the fabric. It was found that the zinc film coated on Ag film before RF reactive sputtering could protect the silver film from oxidation. Anti-ultraviolet property and antistatic property of the coated samples using different magnetron sputtering methods were also investigated. The experimental results showed that Ag film was oxidized into in Ag{sub 2}O film in high vacuum oxygen environment. The deposition of Zn film on the surface of the fabric coated with Ag film before RF reactive sputtering, could successfully obtained Ag/ZnO composite film, and also generated structural color on the polyester fabric.

Emission and Dynamics of Charge Carriers in Uncoated and Organic/Metal Coated Semiconductor Nanowires

Science.gov (United States)

Kaveh Baghbadorani, Masoud

In this dissertation, the dynamics of excitons in hybrid metal/organic/nanowire structures possessing nanometer thick deposited molecular and metal films on top of InP and GaAs nanowire (NW) surfaces were investigated. Optical characterizations were carried out as a function of the semiconductor NW material, design, NW size and the type and thickness of the organic material and metal used. Hybrid organic and plasmonic semiconductor nanowire heterostructures were fabricated using organic molecular beam deposition technique. I investigated the photon emission of excitons in 150 nm diameter polytype wurtzite/zincblende InP NWs and the influence of a few ten nanometer thick organic and metal films on the emission using intensity- and temperature-dependent time-integrated and time resolved (TR) photoluminescence (PL). The plasmonic NWs were coated with an Aluminum quinoline (Alq3) interlayer and magnesium-silver (Mg0.9:Ag0.1) top layer. In addition, the nonlinear optical technique of heterodyne four-wave mixing was used (in collaboration with Prof. Wolfgang Langbein, University of Cardiff) to study incoherent and coherent carrier relaxation processes on bare nanowires on a 100 femtosecond time-scale. Alq3 covered NWs reveal a stronger emission and a longer decay time of exciton transitions indicating surface state passivation at the Alq3/NW interface. Alq3/Mg:Ag NWs reveal a strong quenching of the exciton emission which is predominantly attributed to Forster energy-transfer from excitons to plasmon oscillations in the metal cluster film. Changing the Mg:Ag to gold and the organic Alq3 spacer layer to PTCDA leads to a similar behavior, but the PL quenching is strongly increased. The observed behavior is attributed to a more continuous gold deposition leading to an increased Forster energy transfer and to a metal induced band-bending. I also investigated ensembles of bare and gold/Alq3 coated GaAs-AlGaAs-GaAs core shell NWs of 130 nm diameter. Plasmonic NWs with Au

Analysis of the stability of native oxide films at liquid lead/metal interfaces

International Nuclear Information System (INIS)

Lesueur, C.; Chatain, D.; Gas, P.; Bergman, C.; Baque, F.

2002-01-01

The interface between liquid lead and different metallic solids (pure metals: Al, Fe and Ni, and T91 steel) was investigated below 400 deg C under ultrahigh vacuum (UHV) by wetting experiments. The aim was to check the physical stability of native oxide films grown at the surface of the substrates, along a contact with liquid lead. Two types of metallic substrates were used: i) conventional bulk polycrystals, and ii) nanocrystalline films obtained by e-beam evaporation under UHV. The actual contact between liquid lead and the solid substrates was achieved by preparing lead drops in-situ. Wetting experiments were performed using sessile drop and/or liquid bridge methods. Fresh solid surfaces and former liquid/solid interfaces can be explored by squeezing and stretching a liquid lead bridge formed between two parallel and horizontal substrates. It is shown that the contact with liquid lead produces the detachment of the native oxide films grown on the metallic solids. It is concluded that if oxide coatings are needed to protect a metallic solid from attack by liquid lead, they should be self-renewable. (authors)

Improving the scratch resistance of sol-gel metal oxide coatings cured at 250 C through use of thermogenerated amines

NARCIS (Netherlands)

Langanke, J.; Arfsten, N.; Buskens, P.; Habets, R.; Klankermayer, J.; Leitner, W.

2013-01-01

Scratch resistant sol-gel metal oxide coatings typically require a thermal post-treatment step (curing process) at temperatures between 400 and 700 C. In this report, we demonstrate that the in situ generation of amines within sol-gel films facilitates the preparation of scratch resistant metal

Pulsed laser deposition of YBCO films on ISD MgO buffered metal tapes

CERN Document Server

Ma, B; Koritala, R E; Fisher, B L; Markowitz, A R; Erck, R A; Baurceanu, R; Dorris, S E; Miller, D J; Balachandran, U

2003-01-01

Biaxially textured magnesium oxide (MgO) films deposited by inclined-substrate deposition (ISD) are desirable for rapid production of high-quality template layers for YBCO-coated conductors. High-quality YBCO films were grown on ISD MgO buffered metallic substrates by pulsed laser deposition (PLD). Columnar grains with a roof-tile surface structure were observed in the ISD MgO films. X-ray pole figure analysis revealed that the (002) planes of the ISD MgO films are tilted at an angle from the substrate normal. A small full-width at half maximum (FWHM) of approx 9deg was observed in the phi-scan for ISD MgO films deposited at an inclination angle of 55deg . In-plane texture in the ISD MgO films developed in the first approx 0.5 mu m from the substrate surface, and then stabilized with further increases in film thickness. Yttria-stabilized zirconia and ceria buffer layers were deposited on the ISD MgO grown on metallic substrates prior to the deposition of YBCO by PLD. YBCO films with the c-axis parallel to the...

Growth and Filling Regularities of Filamentary Channels in Non-Metallic Inorganic Coatings Under Anodic Oxidation of Valve Metals. Mathematical Modeling

Science.gov (United States)

Mamaev, A. I.; Mamaeva, V. A.; Kolenchin, N. F.; Chubenko, A. K.; Kovalskaya, Ya. B.; Dolgova, Yu. N.; Beletskaya, E. Yu.

2015-12-01

Theoretical models are developed for growth and filling processes in filamentary channels of nanostructured non-metallic coatings produced by anodizing and microplasma oxidation. Graphical concentration distributions are obtained for channel-reacting anions, cations, and sparingly soluble reaction products depending on the time of electric current transmission and the length of the filamentary channel. Graphical distributions of the front moving velocity for the sparingly soluble compound are presented. The resulting model representation increases the understanding of the anodic process nature and can be used for a description and prediction of porous anodic film growth and filling. It is shown that the character of the filamentary channel growth and filling causes a variety of processes determining the textured metal - nonmetallic inorganic coating phase boundary formation.

Investigation on the minimum film boiling temperature on metallic and ceramic heaters

International Nuclear Information System (INIS)

Ladisch, R.

1980-06-01

The minimum film boiling temperature on ceramic and metallic heaters has been experimentally studied. The knowledge of this temperature boundary is important in safety considerations on all liquid cooled nuclear reactors. The experiments have been carried out by quenching a hot metal cylinder with and without ceramic coating of aluminium in water. Results show that the minimum film boiling temperature Tsub(min) increases with water subcooling and is dependend upon the thermophysical properties of the heating surface. The roughness of the heater does not affect Tsub(min). At low subcoolings the vapour film is more stable and seems to break down when the specific heatflux upon liquid solid contact is lower than a threshold value above which film boiling can be reestablished. At higher subcoolings instead the vapour film is thinner and more stable. In this case the surface temperature decreases beyond the value by which the specific heatflux upon liquid solid contact would be lower than the threshold value. As soon as the vapour film becomes unstable, it collapses. (orig.) [de

Self-optimized metal coatings for fiber plasmonics by electroless deposition.

Science.gov (United States)

Bialiayeu, A; Caucheteur, C; Ahamad, N; Ianoul, A; Albert, J

2011-09-26

We present a novel method to prepare optimized metal coatings for infrared Surface Plasmon Resonance (SPR) sensors by electroless plating. We show that Tilted Fiber Bragg grating sensors can be used to monitor in real-time the growth of gold nano-films up to 70 nm in thickness and to stop the deposition of the gold at a thickness that maximizes the SPR (near 55 nm for sensors operating in the near infrared at wavelengths around 1550 nm). The deposited films are highly uniform around the fiber circumference and in spite of some nanoscale roughness (RMS surface roughness of 5.17 nm) the underlying gratings show high quality SPR responses in water. © 2011 Optical Society of America

Effect of different sound atmospheres on SnO2:Sb thin films prepared by dip coating technique

Science.gov (United States)

Kocyigit, Adem; Ozturk, Erhan; Ejderha, Kadir; Turgut, Guven

2017-11-01

Different sound atmosphere effects were investigated on SnO2:Sb thin films, which were deposited with dip coating technique. Two sound atmospheres were used in this study; one of them was nay sound atmosphere for soft sound, another was metallic sound for hard sound. X-ray diffraction (XRD) graphs have indicated that the films have different orientations and structural parameters in quiet room, metallic and soft sound atmospheres. It could be seen from UV-Vis spectrometer measurements that films have different band gaps and optical transmittances with changing sound atmospheres. Scanning electron microscope (SEM) and AFM images of the films have been pointed out that surfaces of films have been affected with changing sound atmospheres. The electrical measurements have shown that films have different I-V plots and different sheet resistances with changing sound atmospheres. These sound effects may be used to manage atoms in nano dimensions.

A method for probing the effects of conformal nanoscale coatings on fatigue crack initiation in electroplated Ni films

International Nuclear Information System (INIS)

Straub, T.; Baumert, E.K.; Eberl, C.; Pierron, O.N.

2012-01-01

This paper describes an experimental technique to identify robust nanoscale coatings for improving the long-term reliability of metallic microelectromechanical systems. More specifically, the influence of nanoscale alumina coatings on the fatigue crack initiation process in 20 μm thick electrodeposited Ni films was investigated in a mild (30 °C, 50% RH) and harsh (80 °C, 90% RH) environment. Atomic-layer-deposited alumina layers, with thicknesses of 5 and 25 nm, were coated on Ni fatigue micro-resonators, and the fatigue degradation behavior in the very high cycle fatigue regime was compared to that of uncoated structures. Evidence based on post-test scanning electron microscopy and resonant frequency evolution plots shows that the coatings do not prevent the formation of fatigue extrusions and micro-cracks. However, their formation is likely delayed for the 25 nm thick alumina-coated Ni films. - Highlights: ► Effect of alumina coatings (5 and 25 nm thick) on fatigue initiation in nickel films ► Fatigue tests were performed at 30 °C, 50% relative humidity (RH) and 80 °C, 90% RH. ► Coatings did not prevent fatigue extrusions and micro-cracks. ► 25 nm coatings likely delayed the formation of fatigue extrusions and micro-cracks. ► The technique can be used to identify reliable nanoscale coatings.

Mechanical properties of molybdenum coated with titanium carbide film

International Nuclear Information System (INIS)

Shikama, T.; Shinno, H.; Fukutomi, M.; Fujitsuka, M.; Okada, M.

1983-01-01

TiC-coated molybdenum is mechanically tensile tested. The 6 μm thick TiC-coated molybdenum has a higher 0.2% proof strength with a slight decrease in uniform and rupture elongation than the uncoated one. This strengthening effect of the TiC coating can be explained by the constrained effect of the high strength TiC film. The 1.2 μm thick TiC-coated molybdenum starts its plastic deformation at a lower stress than the uncoated one. Also, the coating makes the stress-strain curve more smooth. These effects are attributed to the surface effect, namely, that the interface between the molybdenum substrate and the strong and brittle TiC film acts as a strong dislocation source. The compressive stress in the TiC film will also help the start of plastic deformation at lower external stresses. (author)

Study progression in application of process analytical technologies on film coating

Directory of Open Access Journals (Sweden)

Tingting Peng

2015-06-01

Full Text Available Film coating is an important unit operation to produce solid dosage forms, thereby, the monitoring of this process is helpful to find problems in time and improve the quality of coated products. Traditional methods adopted to monitor this process include measurement of coating weight gain, performance of disintegration and dissolution test, etc. However, not only do these methods cause destruction to the samples, but also consume time and energy. There have recently emerged the applications of process analytical technologies (PAT on film coating, especially some novel spectroscopic and imaging technologies, which have the potential to real-time track the progress in film coating and optimize production efficiency. This article gives an overview on the application of such technologies for film coating, with the goal to provide a reference for the further researches.

Multifunctionality in coating films including Nb-doped TiO2 and Cs x WO3: near infrared shielding and photocatalytic properties

Science.gov (United States)

Asakura, Yusuke; Anada, Yuto; Hamanaka, Ryo; Sato, Tsugio; Katsumata, Ken-ichi; Wu, Xiaoyong; Yin, Shu

2018-06-01

Various types of coating films were obtained from hydrothermally synthesized Nb-doped TiO2 (NTO) and Cs x WO3 (CWO) nanoparticles. The coating films possessed multifunctionality including near infrared (NIR) absorption and photocatalysis abilities. The NTO and CWO nanoparticles were synthesized by a unique solvothermal reaction in which water induced by an esterification reaction between alcohol and carboxylic acid can act as a hydrolyzing agent for metal precursors. NTO was synthesized by the unique solvothermal reaction for the first time. The reaction accompanied by the reduction of Ti4+ to Ti3+ led to the formation of nanoparticles with both NIR absorption and photocatalytic properties. The effect of the ethanol–acetic acid ratio on the morphology of the obtained NTO was investigated, and the larger amount of acetic acid led to a larger nanoparticle size, indicating the size controllability. The two types of coating film, including CWO and NTO nanoparticles, were obtained for comparison: (1) coexistent coating film: one side of the quartz glass was coated with a dispersion, including both CWO and NTO nanoparticles, and (2) double-sided coating film: a quartz glass coated with a CWO dispersion on one side and an NTO dispersion on the other side. The double-sided coating led to higher multifunctionality. Furthermore, the optimized condition for the double-sided coating was investigated by using various NTO particles obtained using different ethanol–acetic acid ratios.

Structural characterization and comparison of iridium, platinum and gold/palladium ultra-thin film coatings for STM of biomolecules

Energy Technology Data Exchange (ETDEWEB)

Sebring, R.; Arendt, P.; Imai, B.; Bradbury, E.M.; Gatewood, J. [Los Alamos National Lab., NM (United States); Panitz, J. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Physics and Astronomy; Yau, P. [Univ. of California, Davis, CA (United States)

1997-10-30

Scanning tunneling microscopy (STM) is capable of atomic resolution and is ideally suited for imaging surfaces with uniform work function. A biological sample on a conducting substrate in air does not meet this criteria and requires a conductive coating for stable and reproducible STM imaging. In this paper, the authors describe the STM and transmission electron microscopy (TEM) characterization of ultra-thin ion-beam sputtered films of iridium and cathode sputtered gold/palladium and platinum films on highly ordered pyrolytic graphite (HOPG) which were developed for use as biomolecule coatings. The goals were the development of metal coatings sufficiently thin and fine grained that 15--20 {angstrom} features of biological molecules could be resolved using STM, and the development of a substrate/coating system which would allow complementary TEM information to be obtained for films and biological molecules. The authors demonstrate in this paper that ion-beam sputtered iridium on highly ordered pyrolytic graphite (HOPG) has met both these goals. The ion-beam sputtered iridium produced a very fine grained (< 10 {angstrom}) continuous film at 5--6 {angstrom} thickness suitable for stable air STM imaging. In comparison, cathode sputtered platinum produced 16 {angstrom} grains with the thinnest continuous film at 15 {angstrom} thickness, and the sputtered gold/palladium produced 25 {angstrom} grains with the thinnest continuous film at 18 {angstrom} thickness.

Advanced fabrication method for the preparation of MOF thin films: Liquid-phase epitaxy approach meets spin coating method.

KAUST Repository

Chernikova, Valeriya; Shekhah, Osama; Eddaoudi, Mohamed

2016-01-01

Here we report a new and advanced method for the fabrication of highly oriented/polycrystalline metal-organic framework (MOF) thin films. Building on the attractive features of the liquid-phase epitaxy (LPE) approach, a facile spin coating method

Insights on the Role of Copper Addition in the Corrosion and Mechanical Properties of Binary Zr-Cu Metallic Glass Coatings

Directory of Open Access Journals (Sweden)

Junlei Tang

2017-12-01

Full Text Available The effect of copper addition on the corrosion resistance and mechanical properties of binary Zr100–xCux (x = 30, 50, 80, 90 at.% glassy coatings was investigated by means of electrochemical measurements, scanning electron microscopy (SEM, energy dispersive analysis spectroscopy (EDS, X-ray photoelectron spectroscopy (XPS and nano-indentation techniques. The corrosion resistance in 0.01 M deaerated H2SO4 solution and the mechanical properties of the Zr-Cu glassy coatings depend considerably upon the copper content in the glassy matrix. The top surfaces of the Zr-Cu coatings with lower Cu content were covered by a compact protective ZrO2 passive film. The competition between the oxidation of Zr atoms (ZrO2 film formation and the oxidation–dissolution of Cu atoms assumed the most important role in the electrochemical behavior of the Zr-Cu glassy coatings. The generation of ZrO2 on the surface benefited the formation of passive film; and the corrosion resistance of the metallic glass coatings depended on the coverage degree of ZrO2 passive film. The evolution of free volume affected both the mechanical and corrosion behaviors of the Zr-Cu glassy coatings.

Thin films

International Nuclear Information System (INIS)

Strongin, M.; Miller, D.L.

1976-01-01

This article reviews the phenomena that occur in films from the point of view of a solid state physicist. Films form the basis for many established and developing technologies. Metal layers have always been important for optical coatings and as protective coatings. In the most sophisticated cases, films and their interaction on silicon surfaces form the basis of modern electronic technology. Films of silicon, GaAs and composites of these materials promise to lead to practical photovoltaic devices

Imprinting of metal receptors into multilayer polyelectrolyte films: fabrication and applications in marine antifouling

OpenAIRE

Puniredd, S.R.; Janczewski, D.; Go, D.P.; Zhu, X.; Guo, S.; Teo, S.L-M.; Lee, S.S.C.; Vancso, Gyula J.

2015-01-01

Polymeric films constructed using the layer-by-layer (LbL) fabrication process were employed as a platform for metal ion immobilization and applied as a marine antifouling coating. The novel Cu2+ ion imprinting process described is based on the use of metal ion templates and LbL multilayer covalent cross-linking. Custom synthesized, peptide mimicking polycations composed of histidine grafted poly(allylamine) (PAH) to bind metal ions, and methyl ester containing polyanions for convenient cross...

Ionic Transport Through Metal-Rich Organic Coatings

Science.gov (United States)

2016-08-19

important for metal substrates, as it is well-known that chloride increases corrosion of metals . 3 For metal -loaded primers, it has been established...volume (MPV) percent, solvent polarity, and resin molecular weight impact corrosion protection of metal -rich organic (MRO) coatings. Following design of...pH and chloride ion concentration levels over time. As the corrosion protection of the coating decreases, chloride ion concentration will increase

Use of buffy coat thick films in detecting malaria parasites in patients with negative conventional thick films.

Science.gov (United States)

Duangdee, Chatnapa; Tangpukdee, Noppadon; Krudsood, Srivicha; Wilairatana, Polrat

2012-04-01

To determine the frequency of malaria parasite detection from the buffy coat blood films by using capillary tube in falciparum malaria patients with negative conventional thick films. Thirty six uncomplicated falciparum malaria patients confirmed by conventional thick and thin films were included in the study. The patients were treated with artemisinin combination therapy at Hospital for Tropical Diseases, Bangkok, Thailand for 28 day. Fingerpricks for conventional blood films were conducted every 6 hours until negative parasitemia, then daily fingerpricks for parasite checks were conducted until the patients were discharged from hospital. Blood samples were also concurrently collected in 3 heparinized capillary tubes at the same time of fingerpricks for conventional blood films when the prior parasitemia was negative on thin films and parasitemia was lower than 50 parasites/200 white blood cells by thick film. The first negative conventional thick films were compared with buffy coat thick films for parasite identification. Out of 36 patients with thick films showing negative for asexual forms of parasites, buffy coat films could detect remaining 10 patients (27.8%) with asexual forms of Plasmodium falciparum. The study shows that buffy coat thick films are useful and can detect malarial parasites in 27.8% of patients whose conventional thick films show negative parasitemia.

Process optimization of ultrasonic spray coating of polymer films

DEFF Research Database (Denmark)

Bose, Sanjukta; Keller, Stephan Sylvest; Boisen, Anja

2013-01-01

is developed for statistical analysis which identifies the distance between nozzle and substrate as the most significant parameter. Depending on the drying of the sprayed droplets on the substrate, we define two broad regimes, "dry" and "wet". The optimum condition of spraying lies in a narrow window between...... these two regimes, where we obtain a film of desired quality. Both with increasing nozzle-substrate distance and temperature, the deposition moves from a wet state to a dry regime. Similar results are also achieved for solvents with low boiling points. Finally, we study film formation during spray coating......In this work we have performed a detailed study of the influence of various parameters on spray coating of polymer films. Our aim is to produce polymer films of uniform thickness (500 nm to 1 μm) and low roughness compared to the film thickness. The coatings are characterized with respect...

Edible films and coatings: Sources, properties and application

Directory of Open Access Journals (Sweden)

Šuput Danijela Z.

2015-01-01

Full Text Available In order to extend product shelf life while preserving the quality scientific attention focused to biopolymers research that are base for edible films and coatings production. Another major advantage of this kind of food packaging is their eco-friendly status because biopolymers do not cause environmental problems as packaging materials derived from non-renewable energy sources do. Objective of this work was to review recently studied edible films and coatings - their sources, properties and possible application. As sources for edible biopolymers were highlighted polysaccharides, proteins and lipids. The most characteristic subgroups from each large group of compounds were selected and described regarding possible physical and mechanical protection; migration, permeation, and barrier functions. The most important biopolymers characteristic is possibility to act as active substance carriers and to provide controlled release. In order to achieve active packaging functions emulsifiers, antioxidants and antimicrobial agents can also be incorporated into film-forming solutions in order to protect food products from oxidation and microbial spoilage, resulting in quality improvement and enhanced safety. The specific application where edible films and coatings have potential to replace some traditional polymer packaging are explained. It can be concluded that edible films and coatings must be chosen for food packaging purpose according to specific applications, the types of food products, and the major mechanisms of quality deterioration.

Metal ion reactive thin films using spray electrostatic LbL assembly.

Science.gov (United States)

Krogman, Kevin C; Lyon, Katharine F; Hammond, Paula T

2008-11-20

By using the spray-layer-by-layer (Spray-LbL) technique, the number of metal counterions trapped within LbL coatings is significantly increased by kinetically freezing the film short of equilibrium, potentially limiting interchain penetration and forcing chains to remain extrinsically compensated to a much greater degree than observed in the traditional dipped LbL technique. The basis for the enhanced entrapment of metal ions such as Cu2+, Fe2+, and Ag+ is addressed, including the equilibrium driving force for extrinsic compensation by soft versus hard metal ions and the impact of Spray-LbL on the kinetics of polymer-ion complexation. These polymer-bound metal-ion coatings are also demonstrated to be effective treatments for air filtration, functionalizing existing filters with the ability to strongly bind toxic industrial compounds such as ammonia or cyanide gases, as well as chemical warfare agent simulants such as chloroethyl ethyl sulfide. On the basis of results reported here, future work could extend this method to include other toxic soft-base ligands such as carbon monoxide, benzene, or organophosphate nerve agents.

Ionic Transport Through Metal-Rich Organic Coatings

Science.gov (United States)

2016-08-19

organic paints, inert metallic layers, and protective oxide layers. 2 Although coatings have been commercially used for many years, the design of new...pigments found in chromates protect the substrate by passivating the metallic surface with an oxide layer. Sacrificial coatings prevent the self...surface, eliminating the components needed for a cathodic reaction to occur. Additionally, organic barrier coatings are protective by preventing

Experimental characterization of electrochemically polymerized polycarbazole film and study of its behavior with different metals contacts

Science.gov (United States)

Srivastava, Aditi; Chakrabarti, P.

2017-12-01

In this paper, we present the method of fabrication, experimental characterization, and comparison of electrical parameters of semiconducting polycarbazole film with different rectifying metals contacts. Electrochemical polymerization and deposition of organic semiconductor, i.e., polycarbazole on ITO-coated glass substrate, were performed using an electrochemical workstation. Experimental characterization of the prepared polymer film was done in respect of morphology, absorption, bandgap, and thickness. The stability and electro-activity of polycarbazole film were verified by the cyclic voltammetric method. Study of the behavior of prepared polycarbazole film with the different metals contacts such as Aluminum, Copper, Tungsten, and Tin has been done using semiconductor device analyzer. Various electrical parameters such as barrier height, ideality factor, and reverse saturation current have been extracted with different metal contacts, and the values were compared and contrasted. The nature of I- V characteristic of polycarbazole film in non-contact mode has also been analyzed using scanning tunneling microscope. The rectifying I- V characteristics obtained with different metals contacts have also been validated by the simulation on Deckbuild platform of the of ATLAS® software tool from Silvaco Inc.

Sprayed and Spin-Coated Multilayer Antireflection Coating Films for Nonvacuum Processed Crystalline Silicon Solar Cells

Directory of Open Access Journals (Sweden)

Abdullah Uzum

2017-01-01

Full Text Available Using the simple and cost-effective methods, spin-coated ZrO2-polymer composite/spray-deposited TiO2-compact multilayer antireflection coating film was introduced. With a single TiO2-compact film on the surface of a crystalline silicon wafer, 5.3% average reflectance (the reflectance average between the wavelengths of 300 nm and 1100 nm was observed. Reflectance decreased further down to 3.3% after forming spin-coated ZrO2 on the spray-deposited TiO2-compact film. Silicon solar cells were fabricated using CZ-Si p-type wafers in three sets: (1 without antireflection coating (ARC layer, (2 with TiO2-compact ARC film, and (3 with ZrO2-polymer composite/TiO2-compact multilayer ARC film. Conversion efficiency of the cells improved by a factor of 0.8% (from 15.19% to 15.88% owing to the multilayer ARC. Jsc was improved further by 2 mA cm−2 (from 35.3 mA cm−2 to 37.2 mA cm−2 when compared with a single TiO2-compact ARC.

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.

Correlation of morphology and barrier properties of thin microwave plasma polymer films on metal substrate

International Nuclear Information System (INIS)

Barranco, V.; Carpentier, J.; Grundmeier, G.

2004-01-01

The barrier properties of thin model organosilicon plasma polymers layers on iron are characterised by means of electrochemical impedance spectroscopy (EIS). Tailored thin plasma polymers of controlled morphology and chemical composition were deposited from a microwave discharge. By the analysis of the obtained impedance diagrams, the evolution of the water uptake φ, coating resistance and polymer capacitance with immersion time were monitored and the diffusion coefficients of the water through the films were calculated. The impedance data correlated well with the chemical structure and morphology of the plasma polymer films with a thickness of less than 100 nm. The composition of the films were determined by means of infrared reflection absorption spectroscopy (IRRAS), X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The morphology of the plasma polymer surface and the interface between the plasma polymer and the metal were characterised using atomic force microscopy (AFM). It could be shown that, at higher pressure, the film roughness increases which is probably due to the adsorption of plasma polymer nanoparticles formed in the plasma bulk and the faster film growth. This leads to voids with a size of a few tens of nanometers at the polymer/metal interface. The film roughness increases from the interface to the outer surface of the film. By lowering the pressure and thereby slowing the deposition rate, the plasma polymers perfectly imitate the substrate topography and lead to an excellent blocking of the metal surface. Moreover, the ratio of siloxane bonds to methyl-silyl groups increases which implies that the crosslink density is higher at lower deposition rate. The EIS data consistently showed higher coating resistance as well as lower interfacial capacitance values and a better stability over time for the film deposited at slower pressure. The diffusion coefficient of water in thin and ultra-thin plasma

21 CFR 175.365 - Vinylidene chloride copolymer coatings for polycarbonate film.

Science.gov (United States)

2010-04-01

... polycarbonate film. 175.365 Section 175.365 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... chloride copolymer coatings for polycarbonate film. Vinylidene chloride copolymer coatings identified in this section and applied on polycarbonate film may be safely used as food-contact surfaces, in...

Surface self-organization in multilayer film coatings

Science.gov (United States)

Shuvalov, Gleb M.; Kostyrko, Sergey A.

2017-12-01

It is a recognized fact that during film deposition and subsequent thermal processing the film surface evolves into an undulating profile. Surface roughness affects many important aspects in the engineering application of thin film materials such as wetting, heat transfer, mechanical, electromagnetic and optical properties. To accurately control the morphological surface modifications at the micro- and nanoscale and improve manufacturing techniques, we design a mathematical model of the surface self-organization process in multilayer film materials. In this paper, we consider a solid film coating with an arbitrary number of layers under plane strain conditions. The film surface has a small initial perturbation described by a periodic function. It is assumed that the evolution of the surface relief is governed by surface and volume diffusion. Based on Gibbs thermodynamics and linear theory of elasticity, we present a procedure for constructing a governing equation that gives the amplitude change of the surface perturbation with time. A parametric study of the evolution equation leads to the definition of a critical undulation wavelength that stabilizes the surface. As a numerical result, the influence of geometrical and physical parameters on the morphological stability of an isotropic two-layered film coating is analyzed.

High-quality substrate for fluorescence enhancement using agarose-coated silica opal film.

Science.gov (United States)

Xu, Ming; Li, Juan; Sun, Liguo; Zhao, Yuanjin; Xie, Zhuoying; Lv, Linli; Zhao, Xiangwei; Xiao, Pengfeng; Hu, Jing; Lv, Mei; Gu, Zhongze

2010-08-01

To improve the sensitivity of fluorescence detection in biochip, a new kind of substrates was developed by agarose coating on silica opal film. In this study, silica opal film was fabricated on glass substrate using the vertical deposition technique. It can provide stronger fluorescence signals and thus improve the detection sensitivity. After coating with agarose, the hybrid film could provide a 3D support for immobilizing sample. Comparing with agarose-coated glass substrate, the agarose-coated opal substrates could selectively enhance particular fluorescence signals with high sensitivity when the stop band of the silica opal film in the agarose-coated opal substrate overlapped the fluorescence emission wavelength. A DNA hybridization experiment demonstrated that fluorescence intensity of special type of agarose-coated opal substrates was about four times that of agarose-coated glass substrate. These results indicate that the optimized agarose-coated opal substrate can be used for improving the sensitivity of fluorescence detection with high quality and selectivity.

Effects of palladium coatings on oxygen sensors of titanium dioxide thin films

International Nuclear Information System (INIS)

Castaneda, L.

2007-01-01

Titanium dioxide (TiO 2 -anatase phase) thin films were deposited by the ultrasonic spray pyrolysis technique employing titanium (IV) oxide acetylacetonate (TiO(acac) 2 ) dissolved in pure methanol as a source material. In order to prepare oxygen sensors, TiO 2 thin films were deposited on interdigitated gold electrodes with contacted alumina substrates. Palladium (Pd) coatings were carried out by vacuum thermal evaporation through a metallic mask. The effect of the surface additive (Pd) on the response of the thin film TiO 2 oxygen sensors was monitored in a mixture with zero-grade air. The electrical characterization (monitoring of the electrical surface resistance with the operation temperature) of the sensors in an atmosphere of oxygen (diluted in zero-grade air) was performed in a vacuum chamber (10 -6 Torr), where the gas pressure can be controlled. The films sensitivity was estimated by the following relation: s=R gas -R 0 /R 0 . The response time of the sensor is defined to be the time needed to reach a 0.9R 0 value when the oxygen excess is removed. The gas-sensing properties of TiO 2 sensors in an atmosphere of 10 4 ppm of oxygen were measured between 100 and 450 deg. C. Experimental results obtained using palladium as a surface additive show that the sensitivity reaches a stationary value of 1.18 for O 2 concentration of 100ppm in zero-grade air at 300 deg. C, which is as high as those reported for oxygen sensors prepared with more expensive and complex techniques. The role and activity of palladium coatings incorporated on solid-state oxygen sensors are determined by their chemical state, aggregation form and interaction with the metal-oxide semiconductor

Antimicrobial properties of Zr–Cu–Al–Ag thin film metallic glass

Energy Technology Data Exchange (ETDEWEB)

Chen, Hsien-Wei; Hsu, Kai-Chieh; Chan, Yu-Chen [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan (China); Duh, Jenq-Gong, E-mail: jgd@mx.nthu.edu.tw [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan (China); Lee, Jyh-Wei [Department of Materials Engineering, Ming Chi University of Technology, Taipei, Taiwan (China); Center for Thin Film Technologies and Applications, Mingchi University of Technology, Taipei, Taiwan (China); Jang, Jason Shian-Ching [Department of Mechanical Engineering, Institute of Materials Science and Engineering, National Central University, Chung-Li, Taiwan (China); Chen, Guo-Ju [Department of Materials Science and Engineering, I-Shou University, Kaohsiung, Taiwan (China)

2014-06-30

Metallic glass as a prominent class of structure and multifunctional materials exhibits several unique properties in mechanical, electrochemical, and thermal properties. This study aimed to realize the advantage of biomedical application and to promote the attainable size of metallic glasses by the physical vapor deposition. The Zr–Cu–Al–Ag thin film metallic glass (TFMG) was deposited on silicon wafer and SUS304 stainless steel substrates by magnetron sputtering with single target. For X-ray diffraction analysis, all TFMGs revealed typical broad peaks around the incident angle of 30 to 50°, suggesting that coatings possess amorphous structure. In addition, diffuse halo ring patterns of transmission electron microscopy indicated a fine amorphorization for TFMG via sputtering process. The variation of surface roughness showed that TFMG derived from higher power of metallic targets revealed rougher morphology. Besides, the roughness of SUS304 stainless steel substrate significantly reduced from 7 nm to about 1 nm after TFMGs were deposited. The microbes of Candida albicans, Escherichia coli, and Pseudomonas aeruginosa were used and cultivated on the TFMG coatings with medium to investigate the antimicrobial properties. In the incubation experiment, the growth of each microbe was recorded by a digital photography system and the growth area was calculated by image processing software. The growth area of the microbes on the TFMG was mostly smaller than that on SUS304 stainless steel ones within incubation time of 72 h, indicating that the TFMGs reveal better antimicrobial capability. Moreover, the coatings exhibit a particularly long-term antimicrobial effect for P. aeruginosa. In summary, the Zr–Cu–Al–Ag prepared by sputtering with a single target device presented superior glass forming ability, and coatings with copper and silver constituents revealed significantly antimicrobial properties. Besides, the surface roughness is another factor to affect the

Antimicrobial properties of Zr–Cu–Al–Ag thin film metallic glass

International Nuclear Information System (INIS)

Chen, Hsien-Wei; Hsu, Kai-Chieh; Chan, Yu-Chen; Duh, Jenq-Gong; Lee, Jyh-Wei; Jang, Jason Shian-Ching; Chen, Guo-Ju

2014-01-01

Metallic glass as a prominent class of structure and multifunctional materials exhibits several unique properties in mechanical, electrochemical, and thermal properties. This study aimed to realize the advantage of biomedical application and to promote the attainable size of metallic glasses by the physical vapor deposition. The Zr–Cu–Al–Ag thin film metallic glass (TFMG) was deposited on silicon wafer and SUS304 stainless steel substrates by magnetron sputtering with single target. For X-ray diffraction analysis, all TFMGs revealed typical broad peaks around the incident angle of 30 to 50°, suggesting that coatings possess amorphous structure. In addition, diffuse halo ring patterns of transmission electron microscopy indicated a fine amorphorization for TFMG via sputtering process. The variation of surface roughness showed that TFMG derived from higher power of metallic targets revealed rougher morphology. Besides, the roughness of SUS304 stainless steel substrate significantly reduced from 7 nm to about 1 nm after TFMGs were deposited. The microbes of Candida albicans, Escherichia coli, and Pseudomonas aeruginosa were used and cultivated on the TFMG coatings with medium to investigate the antimicrobial properties. In the incubation experiment, the growth of each microbe was recorded by a digital photography system and the growth area was calculated by image processing software. The growth area of the microbes on the TFMG was mostly smaller than that on SUS304 stainless steel ones within incubation time of 72 h, indicating that the TFMGs reveal better antimicrobial capability. Moreover, the coatings exhibit a particularly long-term antimicrobial effect for P. aeruginosa. In summary, the Zr–Cu–Al–Ag prepared by sputtering with a single target device presented superior glass forming ability, and coatings with copper and silver constituents revealed significantly antimicrobial properties. Besides, the surface roughness is another factor to affect the

Bottom Extreme-Ultraviolet-Sensitive Coating for Evaluation of the Absorption Coefficient of Ultrathin Film

Science.gov (United States)

Hijikata, Hayato; Kozawa, Takahiro; Tagawa, Seiichi; Takei, Satoshi

2009-06-01

A bottom extreme-ultraviolet-sensitive coating (BESC) for evaluation of the absorption coefficients of ultrathin films such as extreme ultraviolet (EUV) resists was developed. This coating consists of a polymer, crosslinker, acid generator, and acid-responsive chromic dye and is formed by a conventional spin-coating method. By heating the film after spin-coating, a crosslinking reaction is induced and the coating becomes insoluble. A typical resist solution can be spin-coated on a substrate covered with the coating film. The evaluation of the linear absorption coefficients of polymer films was demonstrated by measuring the EUV absorption of BESC substrates on which various polymers were spin-coated.

21 CFR 175.360 - Vinylidene chloride copolymer coatings for nylon film.

Science.gov (United States)

2010-04-01

... film. 175.360 Section 175.360 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... coatings for nylon film. Vinylidene chloride copolymer coatings identified in this section and applied on nylon film may be safely used as food-contact surfaces, in accordance with the following prescribed...

Plasma metallization

International Nuclear Information System (INIS)

Crowther, J.M.

1997-09-01

Many methods are currently used for the production of thin metal films. However, all of these have drawbacks associated with them, for example the need for UHV conditions, high temperatures, exotic metal precursors, or the inability to coat complex shaped objects. Reduction of supported metal salts by non-isothermal plasma treatment does not suffer from these drawbacks. In order to produce and analyse metal films before they become contaminated, a plasma chamber which could be attached directly to a UHV chamber with XPS capability was designed and built. This allowed plasma treatment of supported metal salts and surface analysis by XPS to be performed without exposure of the metal film to the atmosphere. Non-equilibrium plasma treatment of Nylon 66 supported gold(lll) chloride using hydrogen as the feed gas resulted in a 95% pure gold film, the remaining 5% of the film being carbon. If argon or helium were used as the feed gases during plasma treatment the resultant gold films were 100% pure. Some degree of surface contamination of the films due to plasma treatment was observed but was easily removed by argon ion cleaning. Hydrogen plasma reduction of glass supported silver(l) nitrate and palladium(ll) acetate films reveals that this metallization technique is applicable to a wide variety of metal salts and supports, and has also shown the ability of plasma reduction to retain the complex 'fern-like' structures seen for spin coated silver(l) nitrate layers. Some metal salts are susceptible to decomposition by X-rays. The reduction of Nylon 66 supported gold(lll) chloride films by soft X-rays to produce nanoscopic gold particles has been studied. The spontaneous reduction of these X-ray irradiated support gold(lll) chloride films on exposure to the atmosphere to produce gold rich metallic films has also been reported. (author)

Transfer coating by electron initiated polymerization

International Nuclear Information System (INIS)

Nablo, S.V.

1985-01-01

The high speed and depth of cure possible with electron initiated monomer/oligomer coating systems provide many new opportunities for approaches to product finishing. Moreover, the use of transfer or cast coating using films or metallic surfaces offers the ability to precisely control the surface topology of liquid film surfaces during polymerization. Transfer coating such as with textiles has been a commercial process for many years and the synergistic addition of EB technology permits the manufacture of unusual new products. One of these, the casting paper used in the manufacture of vinyl and urethane fabrics, is the first EB application to use a drum surface for pattern replication in the coating. In this case the coated paper is cured against, and then released from, an engraved drum surface. Recent developments in the use of plastic films for transfer have been applied to the manufacture of transfer metallized and coated paper and paperboard products for packaging. Details of these and related processes will be presented as well as a discussion of the typical product areas using this high speed transfer technology. (author)

Elaboration of strontium ruthenium oxide thin films on metal substrates by chemical solution deposition

International Nuclear Information System (INIS)

Seveno, R.; Braud, A.; Gundel, H.W.

2005-01-01

In order to improve the structural interface between a metal substrate and a lead zirconate titanate (Pb(ZrTi)O 3 , PZT) ferroelectric thin film, the elaboration of strontium ruthenium oxide (SrRuO 3 ) by chemical solution deposition is studied. The SrRuO 3 thin films were realized by multiple spin-coating technique and the temperature of the rapid thermal annealing process was optimized. The crystallization behavior was examined by X-ray diffraction; surface analyses using scanning electron microscope and atomic force microscope techniques showed the influence of the SrRuO 3 layer at the interface PZT/metal on the morphology of the ferroelectric thin film. From the electrical measurements, a coercive electric field around 25 kV/cm and a remanent polarization of approximately 30 μC/cm were found

Self Healing Coating/Film Project

Science.gov (United States)

Summerfield, Burton; Thompson, Karen; Zeitlin, Nancy; Mullenix, Pamela; Calle, Luz; Williams, Martha

2015-01-01

Kennedy Space Center (KSC) has been developing self healing materials and technologies. This project seeks to further develop self healing functionality in thin films for applications such as corrosion protective coatings, inflatable structures, space suit materials, and electrical wire insulation.

Characterization of quaternary metal oxide films by synchrotron x-ray fluorescence microprobe

Energy Technology Data Exchange (ETDEWEB)

Perry, D.L.; Thompson, A.C.; Russo, R.E. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)] [and others

1997-04-01

A high demand for thin films in industrial technology has been responsible for the creation of new techniques for the fabrication of such films. One highly effective method for the syntheses of variable composition thin films is pulsed-laser deposition (PLD). The technique has a large number of characteristics which make it an attractive approach for making films. It offers rapid deposition rates, congruent material transfer, simple target requirements from which to make the films, in situ multilayer deposition, and no gas composition or pressure requirements. Additionally, the technique can also afford crystalline films and films with novel structures. Pulsed-laser deposition can be used to make films of semiconductors, insulators, high-temperature superconductors, diamond-like films, and piezoelectric materials. Quaternary metal oxides involving calcium, nickel, and potassium have been shown to be quite effective in the catalysis of coal gasification and methane coupling. One approach to incorporating all three of the metal oxides into one phase is the use of laser ablation to prepare films of the catalysts so that they may be used for coatings, smooth surfaces on which to conduct detailed studies of gas-solid interface reactions that are involved in catalytic processes, and other applications. The problem of dissimilar boiling points of the three metal oxides system is overcome, since the laser ablation process effects the volatilization of all three components from the laser target essentially simultaneously. There is strong interest in gaining an understanding of the chemical and morphological aspects of the films that are deposited. Phenomena such as lattice defects and chemical heterogeneity are of interest. The experimental data discussed here are restricted to the matrix homogeneity of the films themselves for films which were void of microparticles.

Metal (Ag/Ti)-Containing Hydrogenated Amorphous Carbon Nanocomposite Films with Enhanced Nanoscratch Resistance: Hybrid PECVD/PVD System and Microstructural Characteristics.

Science.gov (United States)

Constantinou, Marios; Nikolaou, Petros; Koutsokeras, Loukas; Avgeropoulos, Apostolos; Moschovas, Dimitrios; Varotsis, Constantinos; Patsalas, Panos; Kelires, Pantelis; Constantinides, Georgios

2018-03-30

This study aimed to develop hydrogenated amorphous carbon thin films with embedded metallic nanoparticles (a-C:H:Me) of controlled size and concentration. Towards this end, a novel hybrid deposition system is presented that uses a combination of Plasma Enhanced Chemical Vapor Deposition (PECVD) and Physical Vapor Deposition (PVD) technologies. The a-C:H matrix was deposited through the acceleration of carbon ions generated through a radio-frequency (RF) plasma source by cracking methane, whereas metallic nanoparticles were generated and deposited using terminated gas condensation (TGC) technology. The resulting material was a hydrogenated amorphous carbon film with controlled physical properties and evenly dispersed metallic nanoparticles (here Ag or Ti). The physical, chemical, morphological and mechanical characteristics of the films were investigated through X-ray reflectivity (XRR), Raman spectroscopy, Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Transmission Electron Microscopy (TEM) and nanoscratch testing. The resulting amorphous carbon metal nanocomposite films (a-C:H:Ag and a-C:H:Ti) exhibited enhanced nanoscratch resistance (up to +50%) and low values of friction coefficient (<0.05), properties desirable for protective coatings and/or solid lubricant applications. The ability to form nanocomposite structures with tunable coating performance by potentially controlling the carbon bonding, hydrogen content, and the type/size/percent of metallic nanoparticles opens new avenues for a broad range of applications in which mechanical, physical, biological and/or combinatorial properties are required.

The Effects of Curcuma Longa on the Functionality of Pigmentation for Thin Film Coating

Science.gov (United States)

Marsi, N.; Rus, A. Z. M.; Tan, N. A. M. S.

2017-08-01

This project presents the effects of turmeric (Curcuma Longa) on the functionality of pigmentation was carried out to improve the sustainability, environment impact and reduction of potential cost saving without sacrificing the performance of thin film coating. The Curcuma Longa pigment was extracted by grating the turmeric into small particles at different percentages which is 20%, 40%, 60% and 80% of Curcuma Longa pigment with 3, 6 and 9 layers of coating. The different percentages of Curcuma Longa pigment was formulated and synthesized with polyols by crosslinking agent of glycerol and calcium carbonate into temperature at 140 °C for 2 hours. The results of water droplet test (ASTM D5964) showed the water contact angle was achieved the optimum superhydrophobic characteristic up to 60% of Curcuma Longa at 153°. The formulation of 60% Curcuma Longa was revealed the optimum adhesion resistance test with no flaking and detachment when the coating applied at 9 layers in the classification grading of adhesion test at 5B. It is indicated that the adhesion resistance of thin film coating on metal substrate was obviously increased as the layer of coating as well as the Curcuma Longa pigment percentage up to 60% at 9 layers. This project also highlighted the potential of Curcuma Longa pigment to produce quality in the natural pigmentation as a replacement synthetic pigment which is long-term health hazards.

Hydrogel coating of RVNRL film by electron beam irradiation

International Nuclear Information System (INIS)

Chantara Thevy Ratnam; Khairul Zaman Hj, Mohd Dahlan; Fumio Yoshii; Keizo Makuuchi

1996-01-01

The tackiness properties of Radiation Vulcanized Natural Rubber Latex (RVNRL) film surfaces coated by various monomers have been investigated in order to understand the suitable hydrogels which reduce the tackiness of the film. In this context , different types of monomers namely, N-vinyl-2-pyrrolidone (NVP), N,N-dimethyl amino ethyl amide (DMAEA), acrylic acid (AAc), N-butyl acrylate (n-BA) and 2-hydroxyethyl methacrylate (HEMA) as well as monomer mixtures have been tried with varying degrees of success. It was found that coating the RVNRL with 80% HEMA/20% n-BA by irradiation at 80 kGy using low Energy Electron Beam gave remarkable reduction in surface tackiness of the RVNRL film. Several other attempts were made such as priming with acid and aluminum sulfate, mixing the aluminum sulfate into the monomer and dipping the partially wet RVNRL film into the monomer to enhance the wettability of he monomers with the film. Studies on surface topography revealed that the decrease in tackiness with coating is due to the increase of the surface roughness at 80 kGy, irradiation dose

Transition Metal Coatings for Energy Conversion and Storage; Electrochemical and High Temperature Applications

Science.gov (United States)

Falola, Bamidele Daniel

Energy storage provides sustainability when coupled with renewable but intermittent energy sources such as solar, wave and wind power, and electrochemical supercapacitors represent a new storage technology with high power and energy density. For inclusion in supercapacitors, transition metal oxide and sulfide electrodes such as RuO2, IrO2, TiS2, and MoS2 exhibit rapid faradaic electron-transfer reactions combined with low resistance. The pseudocapacitance of RuO2 is about 720 F/g, and is 100 times greater than double-layer capacitance of activated carbon electrodes. Due to the two-dimensional layered structure of MoS2, it has proven to be an excellent electrode material for electrochemical supercapacitors. Cathodic electrodeposition of MoS2 onto glassy carbon electrodes is obtained from electrolytes containing (NH4)2MoS 4 and KCl. Annealing the as-deposited Mo sulfide deposit improves the capacitance by a factor of 40x, with a maximum value of 360 F/g for 50 nm thick MoS2 films. The effects of different annealing conditions were investigated by XRD, AFM and charge storage measurements. The specific capacitance measured by cyclic voltammetry is highest for MoS2 thin films annealed at 500°C for 3h and much lower for films annealed at 700°C for 1 h. Inclusion of copper as a dopant element into electrodeposited MoS2 thin films for reducing iR drop during film charge/discharge is also studied. Thin films of Cu-doped MoS2 are deposited from aqueous electrolytes containing SCN-, which acts as a complexing agent to shift the cathodic Cu deposition potential, which is much more anodic than that of MoS2. Annealed, Cu-doped MoS2 films exhibit enhanced charge storage capability about 5x higher than undoped MoS2 films. Coal combustion is currently the largest single anthropogenic source of CO2 emissions, and due to the growing concerns about climate change, several new technologies have been developed to mitigate the problem, including oxyfuel coal combustion, which makes CO2

Thin films of metal-organic compounds and metal nanoparticle

Indian Academy of Sciences (India)

Thin films of metal-organic compounds and metal nanoparticle-embedded polymers for nonlinear optical applications. S Philip Anthony Shatabdi Porel D ... Thin films based on two very different metal-organic systems are developed and some nonlinear optical applications are explored. A family of zinc complexes which ...

Protection of zirconium and its alloys by metallic coatings

International Nuclear Information System (INIS)

Loriers, H.; Lafon, A.; Darras, R.; Baque, P.

1968-01-01

At 600 deg. C in an atmosphere of carbon dioxide, zirconium and its alloys undergo corrosion which presents two aspects simultaneously: - formation of a surface layer of zirconia, - dissolution of oxygen in the alloy sub-layer leading to brittleness. The two phenomena greatly restrict the possibilities of using zirconium alloys as a canning material for fuel elements in CO 2 cooled nuclear reactors. An attempt has thus been made to limit, and perhaps to suppress, the corrosion effects in zirconium under these conditions by protecting it with metallic coatings. A first attempt to obtain a protection using copper-based coatings did not produce the result hoped for. Aluminium coatings produced by vacuum evaporation, followed by a consolidating thermal treatment make it possible to prevent the formation of the zirconia layer, but they do not eliminate the hardening effect produced by oxygen diffusion. On the other hand, electrolytically produced chromium deposits whose adherence is improved by a thermal vacuum treatment, counteract both these phenomena simultaneously. A similar result has been obtained with coatings of molybdenum produced by the technique of high-frequency inductive plasma sputtering. The particular effectiveness of the last two types of coatings is due to their structures characterized by the existence of an adherent film of chromium or molybdenum in the free state. (authors) [fr

Phosphorus-containing enamel type coatings on metals

International Nuclear Information System (INIS)

Sedmale, G.; Sedmalis, U.; Kpbjakov, V.

1998-01-01

Experimental data are given on development of temperature resistant glassy electroinsulating coatings for two groups of metals: niobium and its alloys and metals of the Fe-Co group. The development of the coatings is based on the system: BaO-B 2 O 3 (Al 2 O 3 )-SiO 2 -P 2 O 5 with content of P 2 O 5 up to 30 mol %. The formation process of coatings on metals proceeds via formation of intermediate layer with thickness of 4-6 m u m , which in the case of Nb-Zr coatings consists of dense crystalline aggregates, whose composition according to the x-ray phase analysis corresponds to NbP, Al 9 Nb,AlPO 4 , NbPO 3 . In the case Co-Fe alloys the intermediate layer is amorphous, the content of crystalline phases (CoFe 2 O 4 , Fe 2 O 3 ) is low (not more than 10 %). The latter does not significantly influence the magnetic properties of material and provides the electrical insulation at 550-666 deg C. In the case of protective coatings for Nb-Zr metals the formed intermediate layer and glassy surface layer (their total thickness being 40-60 m u m ) provide protection of the metals up to 1000 deg C in the period up to 1000 h. (author)

Bi--Sr--Ca--Cu--O superconducting films fabricated using metal alkoxides

International Nuclear Information System (INIS)

Katayama, S.; Sekine, M.

1991-01-01

Superconducting films in the Bi--Sr--Ca--Cu--O systems were made using metal alkoxides. To prepare a dip-coating solution using a mixed alkoxide solution, insoluble Cu and Bi alkoxides were dissolved by modification with 2-dimethylaminoethanol and formation of a double alkoxide, respectively. Formation of the double alkoxides of Bi with Ca or Sr was confirmed using FT-IR and 1 H-NMR. Bi--Sr--Ca--Cu--O films on yttria-stabilized ZrO 2 and single crystal MgO(100) substrates were made using this solution. The films were closely oriented along the c-axis perpendicular to the substrate. The film on MgO(100) fired at 850 degree C for 48 h showed two resistance drops around 115 and 85 K, corresponding to the high-T c and low-T c phases, respectively, and zero resistance at 72 K

Nanostructured thin films and coatings functional properties

CERN Document Server

Zhang, Sam

2010-01-01

The second volume in ""The Handbook of Nanostructured Thin Films and Coatings"" set, this book focuses on functional properties, including optical, electronic, and electrical properties, as well as related devices and applications. It explores the large-scale fabrication of functional thin films with nanoarchitecture via chemical routes, the fabrication and characterization of SiC nanostructured/nanocomposite films, and low-dimensional nanocomposite fabrication and applications. The book also presents the properties of sol-gel-derived nanostructured thin films as well as silicon nanocrystals e

Enhanced electron emission from coated metal targets: Effect of surface thickness on performance

Directory of Open Access Journals (Sweden)

Saibabu Madas

2018-03-01

Full Text Available In this work, we establish an analytical formalism to address the temperature dependent electron emission from a metallic target with thin coating, operating at a finite temperature. Taking into account three dimensional parabolic energy dispersion for the target (base material and suitable thickness dependent energy dispersion for the coating layer, Fermi Dirac statistics of electron energy distribution and Fowler’s mechanism of the electron emission, we discuss the dependence of the emission flux on the physical properties such as the Fermi level, work function, thickness of the coating material, and operating temperature. Our systematic estimation of how the thickness of coating affects the emission current demonstrates superior emission characteristics for thin coating layer at high temperature (above 1000 K, whereas in low temperature regime, a better response is expected from thicker coating layer. This underlying fundamental behavior appears to be essentially identical for all configurations when work function of the coating layer is lower than that of the bulk target work function. The analysis and predictions could be useful in designing new coated materials with suitable thickness for applications in the field of thin film devices and field emitters.

Enhanced electron emission from coated metal targets: Effect of surface thickness on performance

Science.gov (United States)

Madas, Saibabu; Mishra, S. K.; Upadhyay Kahaly, Mousumi

2018-03-01

In this work, we establish an analytical formalism to address the temperature dependent electron emission from a metallic target with thin coating, operating at a finite temperature. Taking into account three dimensional parabolic energy dispersion for the target (base) material and suitable thickness dependent energy dispersion for the coating layer, Fermi Dirac statistics of electron energy distribution and Fowler's mechanism of the electron emission, we discuss the dependence of the emission flux on the physical properties such as the Fermi level, work function, thickness of the coating material, and operating temperature. Our systematic estimation of how the thickness of coating affects the emission current demonstrates superior emission characteristics for thin coating layer at high temperature (above 1000 K), whereas in low temperature regime, a better response is expected from thicker coating layer. This underlying fundamental behavior appears to be essentially identical for all configurations when work function of the coating layer is lower than that of the bulk target work function. The analysis and predictions could be useful in designing new coated materials with suitable thickness for applications in the field of thin film devices and field emitters.

Phase Evolution of YBa2Cu3O7-x films by all-chemical solution deposition route for coated conductors

DEFF Research Database (Denmark)

Yue, Zhao; Tang, Xiao; Wu, Wei

2014-01-01

In order to understand the all-chemical-solution-deposition (CSD) processes for manufacturing coated conductors, we investigated the phase evolution of YBa2Cu3O7 (YBCO) films deposited by a low-fluorine metal-organic solution deposition (LF-MOD) method on CSD derived Ce0.9La0.1O2/Gd2Zr2O7/Ni......W. It is shown that the phase transition from the pyrolyzed film to fully converted YBCO film in the LF-MOD process is similar to that in typical trifluoroacetates-metal organic deposition (TFA-MOD) processes even though the amount of TFA in the solution is reduced by almost one half compared with typical TFA...

Dry Sintered Metal Coating of Halloysite Nanotubes

Directory of Open Access Journals (Sweden)

James C. Nicholson

2016-09-01

Full Text Available Halloysite nanotubes (HNTs are a naturally-occurring aluminosilicate whose dimensions measure microns in length and tens of nanometers in diameter. Bonding defects between the alumina and silica lead to net negative and positive charges on the exterior and interior lumen, respectively. HNTs have been shown to enhance the material properties of polymer matrices and enable the sustained release of loaded chemicals, drugs, and growth factors. Due to the net charges, these nanotubes can also be readily coated in layered-depositions using the HNT exterior lumen’s net negative charge as the basis for assembly. These coatings are primarily done through wet chemical processes, the majority of which are limited in their use of desired chemicals, due to the polarity of the halloysite. Furthermore, this restriction in the type of chemicals used often requires the use of more toxic chemicals in place of greener options, and typically necessitates the use of a significantly longer chemical process to achieve the desired coating. In this study, we show that HNTs can be coated with metal acetylacetonates—compounds primarily employed in the synthesis of nanoparticles, as metal catalysts, and as NMR shift reagents—through a dry sintering process. This method was capable of thermally decaying the metal acetylacetonate, resulting in a free positively-charged metal ion that readily bonded to the negatively-charged HNT exterior, resulting in metallic coatings forming on the HNT surface. Our coating method may enable greater deposition of coated material onto these nanotubes as required for a desired application. Furthermore, the use of chemical processes using toxic chemicals is not required, thus eliminating exposure to toxic chemicals and costs associated with the disposal of the resultant chemical waste.

Wear behavior of contacting between thin film coating on SKD11 ball and 304 stainless steel disk

Directory of Open Access Journals (Sweden)

Sriprasird, J.

2007-11-01

Full Text Available Wear is a well known problem in metal stamping die, especially on the die working with stainless steel workpiece, in which wear rate is severe. This research considered various types of material coating on tool surface which were regularly practised in modern stamping industry due to the ability to increase wear resistance. The model study of friction "Ball-on-disk" technique was employed throughout this work. The disk was made from stainless steel austenitic grade (SUS304. The ball was made from cold work tool steel, SKD11 (JIS and was hardened to 60±2 HRC. Ball surface conditions selected for this work were non-coated, coated by TiC-CVD, TiCN (TiC/TiCN/TiN Multilayer-CVD and TiCN (TiN/TiCN Double layer-PVD, and treated by VC-TD. Tests were carried out without lubricant. The results show that the coating film and the surface treatment has no effect on the friction coefficient but it can reduce wear rate by 64.1-99.7% at contact pressure condition less than 1,100 MPa. At the higher level of contact pressure, only 2 types of coating, TiCN (Multilayer-CVD and TiC-CVD, can reduce wear rate. The other two, which are TiCN (Double layer-PVD coating film and a surface treatment by VC-TD process, on the contrary increase the rate of wear significantly. This is due to delamination of coating film at high contact pressure. The coating particles of high hardness accelerate wear phenomenon on the tool surface. Therefore, proper selection of tool surface condition depends on level of contact pressure generated in the process.

21 CFR 888.3358 - Hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint metal/polymer/metal semi-constrained... Devices § 888.3358 Hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis. (a) Identification. A hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis is a device...

Elaboration of strontium ruthenium oxide thin films on metal substrates by chemical solution deposition

Energy Technology Data Exchange (ETDEWEB)

Seveno, R. [Universite de Nantes, Institut de Recherche en Electrotechnique et Electronique de Nantes Atlantique (IREENA), 2, rue de la Houssiniere, BP 92208, 44322 Nantes Cedex 3 (France)]. E-mail: raynald.seveno@univ-nantes.fr; Braud, A. [Universite de Nantes, Institut de Recherche en Electrotechnique et Electronique de Nantes Atlantique (IREENA), 2, rue de la Houssiniere, BP 92208, 44322 Nantes Cedex 3 (France); Gundel, H.W. [Universite de Nantes, Institut de Recherche en Electrotechnique et Electronique de Nantes Atlantique (IREENA), 2, rue de la Houssiniere, BP 92208, 44322 Nantes Cedex 3 (France)

2005-12-22

In order to improve the structural interface between a metal substrate and a lead zirconate titanate (Pb(ZrTi)O{sub 3}, PZT) ferroelectric thin film, the elaboration of strontium ruthenium oxide (SrRuO{sub 3}) by chemical solution deposition is studied. The SrRuO{sub 3} thin films were realized by multiple spin-coating technique and the temperature of the rapid thermal annealing process was optimized. The crystallization behavior was examined by X-ray diffraction; surface analyses using scanning electron microscope and atomic force microscope techniques showed the influence of the SrRuO{sub 3} layer at the interface PZT/metal on the morphology of the ferroelectric thin film. From the electrical measurements, a coercive electric field around 25 kV/cm and a remanent polarization of approximately 30 {mu}C/cm were found.

Effect of heat treatment, top coatings and conversion coatings on the corrosion properties of black electroless Ni-P films

Energy Technology Data Exchange (ETDEWEB)

Liu, Y., E-mail: liu_yunli@hotmail.com [R and D Department, MacDermid plc, 198 Golden Hillock Road, Birmingham B11 2PN (United Kingdom); Beckett, D.; Hawthorne, D. [R and D Department, MacDermid plc, 198 Golden Hillock Road, Birmingham B11 2PN (United Kingdom)

2011-02-15

Electroless black nickel-phosphorus plating is an advanced electroless nickel plating process formulated to deposit a black finish when processed through an oxidizing acid solution. Heat treatment, five types of top organic coating techniques and one conversion coating technique with three different experimental conditions were investigated to stabilize the black film and increase the hardness and corrosion resistance. Morphology and compositions of electroless nickel-phosphorous films with or without heat treatment, with five types of top organic coatings, and with three conversion coatings were compared to examine nickel, phosphorus, oxygen, carbon, silicon and chrome contents on the corrosion resistance of black surfaces by energy dispersive X-ray microanalysis and scanning electron microscope. Corrosion resistance of black electroless nickel-phosphorus coatings with or without heat treatment, with five types of top organic coatings, and with three conversion coatings was investigated by the polarization measurements and the salt spray test in 5% NaCl solution, respectively. HydroLac as the top organic coating from MacDermid showed the excellent corrosion resistance and the black EN film did not lose the black color after 48 h salt spray test. Electrotarnil B process with 0.5 ASD for 1 min stabilized the black Ni-P film immediately and increased the hardness and corrosion performance of the black Ni-P film. The black Ni-P coating with Electroarnil B process passed the 5% NaCl salt spray test for 3000 h in the black color and had a minimal corrosion current 0.8547 {mu}A/cm{sup 2} by the polarization measurement.

Electrochemical characterization of Zr-based thin film metallic glass in hydrochloric aqueous solution

International Nuclear Information System (INIS)

Chuang, Ching-Yen; Liao, Yi-Chia; Lee, Jyh-Wei; Li, Chia-Lin; Chu, Jinn P.; Duh, Jenq-Gong

2013-01-01

Recently thin film metallic glass represents a class of promising engineering materials for structural applications. In this work, the Zr-based thin film metallic glass (TFMG) was fabricated on the Si and AISI 420 substrates using a Zr–Cu–Ni–Al alloy and pure Zr metal targets by a pulsed DC magnetron sputtering system. The chemical compositions, crystalline structures, microstructures and corrosion behavior in hydrochloric (HCl) aqueous solutions of Zr-based TFMGs were investigated. The results showed that the surface morphologies of Zr-based TFMG were very smooth. A compact and dense structure without columnar structure was observed. The amorphous structure of Zr-based TFMG was characterized by the X-ray diffractometer and transmission electron microscopy analyses. After the potentiodynamic polarization test, the better corrosion resistance was achieved for the Zr-based TFMG coated AISI 420 in 1 mM HCl aqueous solution. Based on the surface morphologies and chemical analysis results of the corroded surfaces, the pitting, crevice corrosion and filiform corrosion were found. The corrosion mechanisms of the Zr-based TFMG were discussed in this work. - Highlights: ► Zr-based thin film metallic glass with amorphous structure. ► Better corrosion resistance of Zr-based thin film metallic glass observed. ► Pitting, crevice and filiform corrosion reactions revealed. ► The Cu-rich corrosion products found in the pit. ► Nanowire and flaky corrosion products formed adjacent to the filiform corrosion path

Transfer coating by electron initiated polymerization

International Nuclear Information System (INIS)

Nablo, S.V.

1984-01-01

The high speed and depth of cure possible with electron initiated monomer/oligomer coating systems provide many new opportunities for approaches to product finishing. Moreover, the use of transfer or cast coating using films or metallic surfaces offers the ability to precisely control the surface topology of liquid film surfaces during polymerization. Transfer coating such as with textiles has been a commercial process for many years and the synergistic addition of EB technology permits the manufacture of unusual new products. One of these, the casting paper used in the manufacture of vinyl and urethane fabrics, is the first EB application to use a drum surface for pattern replication in the coating. In this case the coated paper is cured against, and then released from, an engraved drum surface. Recent developments in the use of plastic films for transfer have been applied to the manufacture of transfer metallized and coated paper and paperboard products for packaging. Details of these and related processes are presented as well as a discussion of the typical product areas (e.g. photographic papers, release papers, magnetic media) using this high speed transfer technology

Metallic glass coating on metals plate by adjusted explosive welding technique

International Nuclear Information System (INIS)

Liu, W.D.; Liu, K.X.; Chen, Q.Y.; Wang, J.T.; Yan, H.H.; Li, X.J.

2009-01-01

Using an adjusted explosive welding technique, an aluminum plate has been coated by a Fe-based metallic glass foil in this work. Scanning electronic micrographs reveal a defect-free metallurgical bonding between the Fe-based metallic glass foil and the aluminum plate. Experimental evidence indicates that the Fe-based metallic glass foil almost retains its amorphous state and mechanical properties after the explosive welding process. Additionally, the detailed explosive welding process has been simulated by a self-developed hydro-code and the bonding mechanism has been investigated by numerical analysis. The successful welding between the Fe-based metallic glass foil and the aluminum plate provides a new way to obtain amorphous coating on general metal substrates.

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.

Analysis of the plasma impurity influx from alkali-metal coatings for fusion-reactor applications

International Nuclear Information System (INIS)

DeWald, A.B.; Davidson, J.N.; Krauss, A.R.; Gruen, D.M.

1982-01-01

Recently, it has been proposed that alkali-metal covered surfaces be applied to magnetic fusion devices as a means of controlling plasma impurity contamination and shielding the substrate from erosion. Monolayer films of alkali metals have been shown to sputter primarily as ions under particle bombardment. Thus, it is thought that a sheath potential and/or magnetic fields encountered by a sputtered ion will return the ion to the surface without entering the plasma. In this paper, we investigate the net wall impurity influx associated with coatings which exhibit substantial secondary ion emission as compared to those which sputter only as neutral atoms. Included in the analysis are sputtered substrate atoms. These are sometimes found to be a significant fraction of the total sputtering yield for low-Z alkali monolayers and affect the overall performance of such coatings. Estimates of the impurity influx made in the neighborhood of a sheath potential show that secondary-ion emitting coatings are effective as a means of inhibiting plasma impurity contamination and wall erosion

Nano-enabled tribological thin film coatings: global patent scenario.

Science.gov (United States)

Sivudu, Kurva S; Mahajan, Yashwant R; Joshi, Shrikant V

2014-01-01

The aim of this paper is to present current status and future prospects of nano-enabled tribological thin film coatings based on worldwide patent landscape analysis. The study also presents an overview of technological trends by carrying out state-of-the-art literature analysis, including survey of corporate websites. Nanostructured tribological coatings encompass a wide spectrum of nanoscale microstructures, including nanocrystalline, nanolayered, nano-multilayered, nanocomposite, nanogradient structures or their unique combinations, which are composed of single or multi-component phases. The distinct microstructural features of the coatings impart outstanding tribological properties combined with multifunctional attributes to the coated components. Their unique combination of remarkable properties make them ideal candidates for a wide range of applications in diverse fields such as cutting and metalworking tools, biomedical devices, automotive engine components, wear parts, hard disc drives etc. The patent landscape analysis has revealed that nano-enabled tribological thin film coatings have significant potential for commercial applications in view of the lion's share of corporate industry in patenting activity. The largest patent portfolio is held by Japan followed by USA, Germany, Sweden and China. The prominent players involved in this field are Mitsubishi Materials Corp., Sandvik Aktiebolag, Hitachi Ltd., Sumitomo Electric Industries Ltd., OC Oerlikon Corp., and so on. The outstanding potential of nanostructured thin film tribological coatings is yet to be fully unravelled and, therefore, immense opportunities are available in future for microstructurally engineered novel coatings to enhance their performance and functionality by many folds.

Tribological coatings for complex mechanical elements produced by supersonic cluster beam deposition of metal dichalcogenide nanoparticles

Science.gov (United States)

Piazzoni, C.; Buttery, M.; Hampson, M. R.; Roberts, E. W.; Ducati, C.; Lenardi, C.; Cavaliere, F.; Piseri, P.; Milani, P.

2015-07-01

Fullerene-like MoS2 and WS2 nanoparticles can be used as building blocks for the fabrication of fluid and solid lubricants. Metal dichalcogenide films have a very low friction coefficient in vacuum, therefore they have mostly been used as solid lubricants in space and vacuum applications. Unfortunately, their use is significantly hampered by the fact that in the presence of humidity, oxygen and moisture, the low-friction properties of these materials rapidly degrade due to oxidation. The use of closed-cage MoS2 and WS2 nanoparticles may eliminate this problem, although the fabrication of lubricant thin films starting from dichalcogenide nanoparticles is, to date, a difficult task. Here we demonstrate the use of supersonic cluster beam deposition for the coating of complex mechanical elements (angular contact ball bearings) with nanostructured MoS2 and WS2 thin films. We report structural and tribological characterization of the coatings in view of the optimization of tribological performances for aerospace applications.

Overlay metallic-cermet alloy coating systems

International Nuclear Information System (INIS)

Gedwill, M.A.; Glasgow, T.K.; Levine, S.R.

1982-01-01

A substrate, such as a turbine blade, vane, or the like, which is subjected to high temperature use is coated with a base coating of an oxide dispersed, metallic alloy (cermet). A top coating of an oxidation, hot corrosion, erosion resistant alloy of nickel, cobalt, or iron is then deposited on the base coating. A heat treatment is used to improve the bonding. The base coating serves as an inhibitor to interdiffusion between the protective top coating and the substrate. Otherwise, the protective top coating would rapidly interact detrimentally with the substrate and degrade by spalling of the protective oxides formed on the outer surface at elevated temperatures

Overlay metallic-cermet alloy coating systems

Science.gov (United States)

Gedwill, M. A.; Levine, S. R.; Glasgow, T. K. (Inventor)

1984-01-01

A substrate, such as a turbine blade, vane, or the like, which is subjected to high temperature use is coated with a base coating of an oxide dispersed, metallic alloy (cermet). A top coating of an oxidation, hot corrosion, erosion resistant alloy of nickel, cobalt, or iron is then deposited on the base coating. A heat treatment is used to improve the bonding. The base coating serves as an inhibitor to interdiffusion between the protective top coating and the substrate. Otherwise, the protective top coating would rapidly interact detrimentally with the substrate and degrade by spalling of the protective oxides formed on the outer surface at elevated temperatures.

Sol-gel antireflective coating on plastics

Science.gov (United States)

Ashley, Carol S.; Reed, Scott T.

1990-01-01

An antireflection film made from a reliquified sol-gel hydrolyzation, condensation polymeric reaction product of a silicon, alkoxides and/or metal alkoxides, or mixtures thereof. The film is particularly useful for coating plastics.

Metal (Ag/Ti-Containing Hydrogenated Amorphous Carbon Nanocomposite Films with Enhanced Nanoscratch Resistance: Hybrid PECVD/PVD System and Microstructural Characteristics

Directory of Open Access Journals (Sweden)

Marios Constantinou

2018-03-01

Full Text Available This study aimed to develop hydrogenated amorphous carbon thin films with embedded metallic nanoparticles (a–C:H:Me of controlled size and concentration. Towards this end, a novel hybrid deposition system is presented that uses a combination of Plasma Enhanced Chemical Vapor Deposition (PECVD and Physical Vapor Deposition (PVD technologies. The a–C:H matrix was deposited through the acceleration of carbon ions generated through a radio-frequency (RF plasma source by cracking methane, whereas metallic nanoparticles were generated and deposited using terminated gas condensation (TGC technology. The resulting material was a hydrogenated amorphous carbon film with controlled physical properties and evenly dispersed metallic nanoparticles (here Ag or Ti. The physical, chemical, morphological and mechanical characteristics of the films were investigated through X-ray reflectivity (XRR, Raman spectroscopy, Scanning Electron Microscopy (SEM, Atomic Force Microscopy (AFM, Transmission Electron Microscopy (TEM and nanoscratch testing. The resulting amorphous carbon metal nanocomposite films (a–C:H:Ag and a–C:H:Ti exhibited enhanced nanoscratch resistance (up to +50% and low values of friction coefficient (<0.05, properties desirable for protective coatings and/or solid lubricant applications. The ability to form nanocomposite structures with tunable coating performance by potentially controlling the carbon bonding, hydrogen content, and the type/size/percent of metallic nanoparticles opens new avenues for a broad range of applications in which mechanical, physical, biological and/or combinatorial properties are required.

Coating compositions comprising bismuth-alloyed zinc

DEFF Research Database (Denmark)

2008-01-01

The present application discloses (i) a coating composition comprising a particulate zinc-based alloyed material, said material comprising 0.05-0.7% by weight of bismuth (Bi), the D50 of the particulate material being in the range of 2.5-30 µm; (ii) a coated structure comprising a metal structure...... having a first coating of the zinc-containing coating composition applied onto at least a part of the metal structure in a dry film thickness of 5-100 µm; and an outer coating applied onto said zinc-containing coating in a dry film thickness of 30-200 µm; (iii) a particulate zinc-based alloyed material......, wherein the material comprises 0.05-0.7%(w/w) of bismuth (Bi), and wherein the D50 of the particulate material is in the range of 2.5-30 µm; (iv) a composite powder consisting of at least 25%(w/w) of the particulate zinc-based alloyed material, the rest being a particulate material consisting of zinc...

Spinel-based coatings for metal supported solid oxide fuel cells

DEFF Research Database (Denmark)

Stefan, Elena; Neagu, Dragos; Blennow Tullmar, Peter

2017-01-01

Metal supports and metal supported half cells developed at DTU are used for the study of a solution infiltration approach to form protective coatings on porous metal scaffolds. The metal particles in the anode layer, and sometimes even in the support may undergo oxidation in realistic operating...... conditions leading to severe cell degradation. Here, a controlled oxidation of the porous metal substrate and infiltration of Mn and/or Ce nitrate solutions are applied for in situ formation of protective coatings. Our approach consists of scavenging the FeCr oxides formed during the controlled oxidation...... into a continuous and well adhered coating. The effectiveness of coatings is the result of composition and structure, but also of the microstructure and surface characteristics of the metal scaffolds....

Influence of silane films in the zinc coating post-treatment

International Nuclear Information System (INIS)

Costa, Marlla Vallerius da; Menezes, Tiago Lemos; Malfatti, Celia de Fraga; Muller, Iduvirges Lourdes; Oliveira, Claudia Trindade; Bonino, Jean-Pierre

2009-01-01

The sol-gel process based on silanes precursors appeared in recent years as a strong alternative for post-treatment to provide an optimization of the protective efficacy of zinc. Moreover, this process has been used to replace chemical chromating conversion based on hexavalent chromium. The silane films are hybrid compounds that provide characteristics of both polymeric materials, such as flexibility and functional compatibility, and ceramic materials, such as high strength and durability. The present work aimed to evaluate the influence of silane films obtained by dip-coating, on the characteristics of electrodeposited zinc coatings. The xerogel films showed a homogeneous surface and a better performance on the corrosion resistance than zinc coating without post-treatment, what can be confirmed by the electrochemical impedance results. These tests showed that application of the silane film promotes the occurrence of one more time constant compared to pure zinc system, hindering the corrosion process. (author)

Magnesium Diboride thin Films, multilayers, and coatings for SRF cavities

Energy Technology Data Exchange (ETDEWEB)

Xi, Xiaoxing [Temple Univ., Philadelphia, PA (United States)

2017-08-17

Superconducting radio frequency (SRF) cavities currently use low-temperature superconductor niobium, and the Nb SRF cavities have approached the performance levels predicted theoretically. Compared to Nb, MgB₂ becomes superconducting at a much higher temperature and promises a better RF performance in terms of higher quality factor Q and higher acceleration capability. An MgB₂ SRF technology can significantly reduce the operating costs of particle accelerators when these potentials are realized. This project aimed to advance the development of an MgB₂ SRF technology. It had two main objectives: (1) materials issues of MgB₂ thin films and multilayers related to their applications in SRF cavities; and (2) coating single-cell cavities for testing at RF frequencies. The key technical thrust of the project is the deposition of high quality clean MgB₂ films and coatings by the hybrid physical-chemical vapor deposition (HPCVD) technique, which was developed in my group. We have achieved technical progress in each of the two areas. For the first objective, we have confirmed that MgB₂ thin film coatings can be used to effectively enhance the vortex penetration field of an SRF cavity. A vortex is a normal region in the shape of spaghetti that threads through a superconductor. Its existence is due to an applied magnetic field that is greater than a so-called lower critical field, H_c1. Once a vortex enters the superconductor, its movement leads to loss. This has been shown to be the reason for an SRF cavity to break down. Thus, enhancing the magnetic field for a vortex to enter the superconductor that forms the SRF cavity has be a goal of intense research. To this end, Gurevich proposed that a coating of thin superconductor layer can impede the vortex entrance. In this project, we have done two important experiment to test this concept. One, we showed that the enhancement of H_c1 can be

Laser-induced damage to thin film dielectric coatings

International Nuclear Information System (INIS)

Walker, T.W.

1980-01-01

The laser-induced damage thresholds of dielectric thin film coatings have been found to be more than an order of magnitude lower than the bulk material damage thresholds. Prior damage studies have been inconclusive in determining the damage mechanism which is operative in thin films. A program was conducted in which thin film damage thresholds were measured as a function of laser wavelength (1.06 μm, 0.53 μm, 0.35 μm and 0.26 μm), laser pulse length (5 and 15 nanoseconds), film materials and film thickness. The large matrix of data was compared to predictions given by avalanche ionization, multiphoton ionization and impurity theories of laser damage. When Mie absorption cross-sections and the exact thermal equations were included into the impurity theory excellent agreement with the data was found. The avalanche and multiphoton damage theories could not account for most parametric variations in the data. For example, the damage thresholds for most films increased as the film thickness decreased and only the impurity theory could account for this behavior. Other observed changes in damage threshold with changes in laser wavelength, pulse length and film material could only be adequately explained by the impurity theory. The conclusion which results from this study is that laser damage in thin film coatings results from absorbing impurities included during the deposition process

Quantifying Pharmaceutical Film Coating with Optical Coherence Tomography and Terahertz Pulsed Imaging: An Evaluation

Science.gov (United States)

Lin, Hungyen; Dong, Yue; Shen, Yaochun; Zeitler, J Axel

2015-01-01

Spectral domain optical coherence tomography (OCT) has recently attracted a lot of interest in the pharmaceutical industry as a fast and non-destructive modality for quantification of thin film coatings that cannot easily be resolved with other techniques. Because of the relative infancy of this technique, much of the research to date has focused on developing the in-line measurement technique for assessing film coating thickness. To better assess OCT for pharmaceutical coating quantification, this paper evaluates tablets with a range of film coating thickness measured using OCT and terahertz pulsed imaging (TPI) in an off-line setting. In order to facilitate automated coating quantification for film coating thickness in the range of 30–200 μm, an algorithm that uses wavelet denoising and a tailored peak finding method is proposed to analyse each of the acquired A-scan. Results obtained from running the algorithm reveal an increasing disparity between the TPI and OCT measured intra-tablet variability when film coating thickness exceeds 100 μm. The finding further confirms that OCT is a suitable modality for characterising pharmaceutical dosage forms with thin film coatings, whereas TPI is well suited for thick coatings. © 2015 The Authors. Journal of Pharmaceutical Sciences published by Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:3377–3385, 2015 PMID:26284354

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

A study of using femtosecond LIBS in analyzing metallic thin film-semiconductor interface

Science.gov (United States)

Galmed, A. H.; Kassem, A. K.; von Bergmann, H.; Harith, M. A.

2011-01-01

Metals and metal alloys are usually employed as interconnections to guide electrical signals between components into the very large scale integrated (VLSI) devices. These devices demand higher complexity, better performance and lower cost. Thin film is a common geometry for these metallic applications, requiring a substrate for rigidity. Accurate depth profile analysis of coatings is becoming increasingly important with expanding industrial use in technological fields. A number of articles devoted to LIBS applications for depth-resolved analysis have been published in recent years. In the present work, we are studying the ability of femtosecond LIBS to make depth profiling for a Ti thin film of thickness 213 nm deposited onto a silicon (100) substrate before and after thermal annealing. The measurements revealed that an average ablation rates of 15 nm per pulse have been achieved. The thin film was examined using X-Ray Diffraction (XRD) and Atomic Force Microscope (AFM), while the formation of the interface was examined using Rutherford Back Scattering (RBS) before and after annealing. To verify the depth profiling results, a theoretical simulation model is presented that gave a very good agreement with the experimental results.

Chemical resistance of thin film materials based on metal oxides grown by atomic layer deposition

International Nuclear Information System (INIS)

Sammelselg, Väino; Netšipailo, Ivan; Aidla, Aleks; Tarre, Aivar; Aarik, Lauri; Asari, Jelena; Ritslaid, Peeter; Aarik, Jaan

2013-01-01

Etching rate of technologically important metal oxide thin films in hot sulphuric acid was investigated. The films of Al-, Ti-, Cr-, and Ta-oxides studied were grown by atomic layer deposition (ALD) method on silicon substrates from different precursors in large ranges of growth temperatures (80–900 °C) in order to reveal process parameters that allow deposition of coatings with higher chemical resistance. The results obtained demonstrate that application of processes that yield films with lower concentration of residual impurities as well as crystallization of films in thermal ALD processes leads to significant decrease of etching rate. Crystalline films of materials studied showed etching rates down to values of < 5 pm/s. - Highlights: • Etching of atomic layer deposited thin metal oxide films in hot H 2 SO 4 was studied. • Smallest etching rates of < 5 pm/s for TiO 2 , Al 2 O 3 , and Cr 2 O 3 were reached. • Highest etching rate of 2.8 nm/s for Al 2 O 3 was occurred. • Remarkable differences in etching of non- and crystalline films were observed

Iron oxide coating films in soda-lime glass by triboadhesion

Energy Technology Data Exchange (ETDEWEB)

Aguilar, J. O.; Arjona, M. J. [Boulevard Bahia s/n esq. Ignacio Comonfort, Chetumal (Mexico); Rodriguez-Lelis, J. M. [Interior Internado Palmira s/n, Cuernavaca, Morelos (Mexico)

2009-04-15

In the triboadhesion process the coating material is passed through a rotating cotton mop and the substrate to be coated. The cotton mop rotates at high velocity and exerts pressure on the surface of the substrate. The combined effect of pressure and velocity of the coating mop on the substrate increases its temperature close to the melting point, allowing deposition and diffusion of the coating material within the substrate. After it is deposited, its particles are embedded within the base material forming a thin film composite. The amount of the coating material deposited on the substrate has its maximum at the surface and then decreases as a function of the local temperature within the base material. Bearing this in mind, in the present work, triboadhesion is employed to deposit iron oxide in a substrate of soda-lime glass, with the purpose of determining the feasibility of using this technique for solar control coatings. It was found, through electronic scan microscopy, that a composite material film is formed following the coating direction. Reflectance and transmittance tests were carried out on the glass samples. A 20% difference was found in the visible spectral region (VIS), and a reduction between 10 and 20% in the Near Infrared Region (NIR). These results showed that the triboadhesion is a promising technique for the application of thin films for solar control or solar cells

Iron oxide coating films in soda-lime glass by triboadhesion

International Nuclear Information System (INIS)

Aguilar, J. O.; Arjona, M. J.; Rodriguez-Lelis, J. M.

2009-01-01

In the triboadhesion process the coating material is passed through a rotating cotton mop and the substrate to be coated. The cotton mop rotates at high velocity and exerts pressure on the surface of the substrate. The combined effect of pressure and velocity of the coating mop on the substrate increases its temperature close to the melting point, allowing deposition and diffusion of the coating material within the substrate. After it is deposited, its particles are embedded within the base material forming a thin film composite. The amount of the coating material deposited on the substrate has its maximum at the surface and then decreases as a function of the local temperature within the base material. Bearing this in mind, in the present work, triboadhesion is employed to deposit iron oxide in a substrate of soda-lime glass, with the purpose of determining the feasibility of using this technique for solar control coatings. It was found, through electronic scan microscopy, that a composite material film is formed following the coating direction. Reflectance and transmittance tests were carried out on the glass samples. A 20% difference was found in the visible spectral region (VIS), and a reduction between 10 and 20% in the Near Infrared Region (NIR). These results showed that the triboadhesion is a promising technique for the application of thin films for solar control or solar cells

Optical properties of titanium di-oxide thin films prepared by dip coating method

Science.gov (United States)

Biswas, Sayari; Rahman, Kazi Hasibur; Kar, Asit Kumar

2018-05-01

Titanium dioxide (TiO2) thin films were prepared by sol-gel dip coating method on ITO coated glass substrate. The sol was synthesized by hydrothermal method at 90°C. The sol was then used to make TiO2 films by dip coating. After dip coating the rest of the sol was dried at 100°C to make TiO2 powder. Thin films were made by varying the number of dipping cycles and were annealed at 500°C. XRD study was carried out for powder samples that confirms the formation of anatase phase. Transmission spectra of thin films show sharp rise in the violet-ultraviolet transition region and a maximum transmittance of ˜60%. Band gap of the prepared films varies from 3.15 eV to 3.22 eV.

Sub-Micrometer Zeolite Films on Gold-Coated Silicon Wafers with Single-Crystal-Like Dielectric Constant and Elastic Modulus

Energy Technology Data Exchange (ETDEWEB)

Tiriolo, Raffaele [Department of Medical and Surgical Sciences, University Magna Graecia of Catanzaro, Viale Europa 88100 Catanzaro Italy; Rangnekar, Neel [Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Ave SE Minneapolis MN 55455 USA; Zhang, Han [Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Ave SE Minneapolis MN 55455 USA; Shete, Meera [Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Ave SE Minneapolis MN 55455 USA; Bai, Peng [Department of Chemistry and Chemistry Theory Center, University of Minnesota, 207 Pleasant St SE Minneapolis MN 55455 USA; Nelson, John [Characterization Facility, University of Minnesota, 12 Shepherd Labs, 100 Union St. S.E. Minneapolis MN 55455 USA; Karapetrova, Evguenia [Surface Scattering and Microdiffraction, X-ray Science Division, Argonne National Laboratory, 9700 S. Cass Ave, Building 438-D002 Argonne IL 60439 USA; Macosko, Christopher W. [Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Ave SE Minneapolis MN 55455 USA; Siepmann, Joern Ilja [Department of Chemistry and Chemistry Theory Center, University of Minnesota, 207 Pleasant St SE Minneapolis MN 55455 USA; Lamanna, Ernesto [Department of Health Sciences, University Magna Graecia of Catanzaro, Viale Europa 88100 Catanzaro Italy; Lavano, Angelo [Department of Medical and Surgical Sciences, University Magna Graecia of Catanzaro, Viale Europa 88100 Catanzaro Italy; Tsapatsis, Michael [Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Ave SE Minneapolis MN 55455 USA

2017-05-08

A low-temperature synthesis coupled with mild activation produces zeolite films exhibiting low dielectric constant (low-k) matching the theoretically predicted and experimentally measured values for single crystals. This synthesis and activation method allows for the fabrication of a device consisting of a b-oriented film of the pure-silica zeolite MFI (silicalite-1) supported on a gold-coated silicon wafer. The zeolite seeds are assembled by a manual assembly process and subjected to optimized secondary growth conditions that do not cause corrosion of the gold underlayer, while strongly promoting in-plane growth. The traditional calcination process is replaced with a non-thermal photochemical activation to ensure preservation of an intact gold layer. The dielectric constant (k), obtained through measurement of electrical capacitance in a metal-insulator-metal configuration, highlights the ultralow k approximate to 1.7 of the synthetized films, which is among the lowest values reported for an MFI film. There is large improvement in elastic modulus of the film (E approximate to 54 GPa) over previous reports, potentially allowing for integration into silicon wafer processing technology.

Interfacial delamination in polymer coated metal sheet : a numerical-experimental study

NARCIS (Netherlands)

van den Bosch, M.

2007-01-01

An increasing amount of products are nowadays made of polymer coated metal sheet. Polymer coated metal has several advantages compared to traditionally Sn (tin) coated metal, such as costs savings and a more environmental friendly production process. Beverage and food cans are formed by draw-redraw

Photo-Curable Metal-Chelating Coatings Offer a Scalable Approach to Production of Antioxidant Active Packaging.

Science.gov (United States)

Lin, Zhuangsheng; Goddard, Julie

2018-02-01

Synthetic metal chelators (for example, ethylenediaminetetraacetic acid, EDTA) are widely used as additives to control trace transition metal induced oxidation in consumer products. To enable removal of synthetic chelators in response to increasing consumer demand for clean label products, metal-chelating active food packaging technologies have been developed with demonstrated antioxidant efficacy in simulated food systems. However, prior work in fabrication of metal-chelating materials leveraged batch chemical reactions to tether metal-chelating ligands, a process with limited industrial translatability for large-scale fabrication. To improve the industrial translatability, we have designed a 2-step laminated photo-grafting process to introduce metal chelating functionality onto common polymeric packaging materials. Iminodiacetic acid (IDA) functionalized materials were fabricated by photo-grafting poly(acrylic acid) onto polypropylene (PP) films, followed by a second photo-grafting process to graft-polymerize an IDA functionalized vinyl monomer (GMA-IDA). The photo-grafting was conducted under atmospheric conditions and was completed in 2 min. The resulting IDA functionalized metal-chelating material was able to chelate iron and copper, and showed antioxidant efficacy against ascorbic acid degradation, supporting its potential to be used synergistically with natural antioxidants for preservation of food and beverage products. The 2-step photo-grafting process improves the throughput of active packaging coatings, enabling potential roll-to-roll fabrication of metal-chelating active packaging materials for antioxidant food packaging applications. To address consumer and retail demands for "clean label" foods and beverages without a corresponding loss in product quality and shelf life, producers are seeking next generation technologies such as active packaging. In this work, we will report the synthesis of metal-chelating active packaging films, which enable removal

Optimized thin film coatings for passive radiative cooling applications

Science.gov (United States)

Naghshine, Babak B.; Saboonchi, Ahmad

2018-03-01

Passive radiative cooling is a very interesting method, which lays on low atmospheric downward radiation within 8-13 μm waveband at dry climates. Various thin film multilayer structures have been investigated in numerous experimental studies, in order to find better coatings to exploit the full potential of this method. However, theoretical works are handful and limited. In this paper, the Simulated Annealing and Genetic Algorithm are used to optimize a thin film multilayer structure for passive radiative cooling applications. Spectral radiative properties are calculated through the matrix formulation. Considering a wide range of materials, 30 high-potential convective shields are suggested. According to the calculations, cooling can be possible even under direct sunlight, using the introduced shields. Moreover, a few water-soluble materials are studied for the first time and the results show that, a KBr substrate coated by a thin CaF2 or polyethylene film can is very close to an ideal coating for passive radiative cooling at night.

Effect of the metal concentration on the structural, mechanical and tribological properties of self-organized a-C:Cu hard nanocomposite coatings

International Nuclear Information System (INIS)

Pardo, A.; Buijnsters, J.G.; Endrino, J.L.; Gómez-Aleixandre, C.; Abrasonis, G.; Bonet, R.; Caro, J.

2013-01-01

The influence of the metal content (Cu: 0–28 at.%) on the structural, mechanical and tribological properties of amorphous carbon films grown by pulsed filtered cathodic vacuum arc deposition is investigated. Silicon and AISI 301 stainless steel have been used as substrate materials. The microstructure, composition and bonding structure have been determined by scanning electron microscopy, combined Rutherford backscattered spectroscopy-nuclear reaction analysis, and Raman spectroscopy, respectively. The mechanical and tribological properties have been assessed using nanoindentation and reciprocating sliding (fretting tests) and these have been correlated with the elemental composition of the films. A self-organized multilayered structure consisting of alternating carbon and copper metal nanolayers (thickness in the 25–50 nm range), whose formation is enhanced by the Cu content, is detected. The nanohardness and Young’s modulus decrease monotonically with increasing Cu content. A maximum value of the Young’s modulus of about 255 GPa is obtained for the metal-free film, whereas it drops to about 174 GPa for the film with a Cu content of 28 at.%. In parallel, a 50% drop in the nanohardness from about 28 GPa towards 14 GPa is observed for these coatings. An increase in the Cu content also produces an increment of the coefficient of friction in reciprocating sliding tests performed against a corundum ball counterbody. As compared to the metal free film, a nearly four times higher coefficient of friction value is detected in the case of a Cu content of 28 at.%. Nevertheless, the carbon–copper composite coatings produced a clear surface protection of the substrate despite an overall increase in wear loss with increasing Cu content in the range 3–28 at.%.

Effect of the metal concentration on the structural, mechanical and tribological properties of self-organized a-C:Cu hard nanocomposite coatings

Science.gov (United States)

Pardo, A.; Buijnsters, J. G.; Endrino, J. L.; Gómez-Aleixandre, C.; Abrasonis, G.; Bonet, R.; Caro, J.

2013-09-01

The influence of the metal content (Cu: 0-28 at.%) on the structural, mechanical and tribological properties of amorphous carbon films grown by pulsed filtered cathodic vacuum arc deposition is investigated. Silicon and AISI 301 stainless steel have been used as substrate materials. The microstructure, composition and bonding structure have been determined by scanning electron microscopy, combined Rutherford backscattered spectroscopy-nuclear reaction analysis, and Raman spectroscopy, respectively. The mechanical and tribological properties have been assessed using nanoindentation and reciprocating sliding (fretting tests) and these have been correlated with the elemental composition of the films. A self-organized multilayered structure consisting of alternating carbon and copper metal nanolayers (thickness in the 25-50 nm range), whose formation is enhanced by the Cu content, is detected. The nanohardness and Young’s modulus decrease monotonically with increasing Cu content. A maximum value of the Young’s modulus of about 255 GPa is obtained for the metal-free film, whereas it drops to about 174 GPa for the film with a Cu content of 28 at.%. In parallel, a 50% drop in the nanohardness from about 28 GPa towards 14 GPa is observed for these coatings. An increase in the Cu content also produces an increment of the coefficient of friction in reciprocating sliding tests performed against a corundum ball counterbody. As compared to the metal free film, a nearly four times higher coefficient of friction value is detected in the case of a Cu content of 28 at.%. Nevertheless, the carbon-copper composite coatings produced a clear surface protection of the substrate despite an overall increase in wear loss with increasing Cu content in the range 3-28 at.%.

Effect of applied potential on passivation and erosion–corrosion of a Fe-based amorphous metallic coating under slurry impingement

International Nuclear Information System (INIS)

Zheng, Z.B.; Zheng, Y.G.; Sun, W.H.; Wang, J.Q.

2014-01-01

Highlights: • The passive current density of coating increases with the increasing potential. • Preferential dissolution of high-valence oxides happens at high applied potential. • More chlorides exist in the passive film at high film formation potential. • Critical flow velocity under impingement is related to resistance of passive film. - Abstract: The passive behaviour and erosion–corrosion behaviour of a HVOF sprayed Fe-based amorphous metallic coating have been investigated in 3.5 wt.% NaCl solution by using potentiostatic polarisation, X-ray photoelectron spectroscopy and Mott–Schottky analysis. The fact that passive current density increased with rising potential might result from the preferential dissolution of high-valence oxides and the existence of more chlorides at a higher potential. The critical flow velocity decreased with rising potential because of the lower resistance of passive film at a higher potential. The reason why passive current density changed under jet impingement was discussed by a simple formula

Preparation of bone-implants by coating hydroxyapatite nanoparticles on self-formed titanium dioxide thin-layers on titanium metal surfaces

Energy Technology Data Exchange (ETDEWEB)

Wijesinghe, W.P.S.L.; Mantilaka, M.M.M.G.P.G.; Chathuranga Senarathna, K.G. [Department of Chemistry, Faculty of Science, University of Peradeniya, 20400 Peradeniya (Sri Lanka); Postgraduate Institute of Science, University of Peradeniya, 20400 Peradeniya (Sri Lanka); Herath, H.M.T.U. [Postgraduate Institute of Science, University of Peradeniya, 20400 Peradeniya (Sri Lanka); Department of Medical Laboratory Science, Faculty of Allied Health Sciences, University of Peradeniya, 20400 Peradeniya (Sri Lanka); Premachandra, T.N. [Department of Veterinary Pathobiology, Faculty of Veterinary Medicine, University of Peradeniya, 20400 Peradeniya (Sri Lanka); Ranasinghe, C.S.K. [Department of Chemistry, Faculty of Science, University of Peradeniya, 20400 Peradeniya (Sri Lanka); Postgraduate Institute of Science, University of Peradeniya, 20400 Peradeniya (Sri Lanka); Rajapakse, R.P.V.J. [Postgraduate Institute of Science, University of Peradeniya, 20400 Peradeniya (Sri Lanka); Department of Veterinary Pathobiology, Faculty of Veterinary Medicine, University of Peradeniya, 20400 Peradeniya (Sri Lanka); Rajapakse, R.M.G., E-mail: rmgr@pdn.ac.lk [Department of Chemistry, Faculty of Science, University of Peradeniya, 20400 Peradeniya (Sri Lanka); Postgraduate Institute of Science, University of Peradeniya, 20400 Peradeniya (Sri Lanka); Edirisinghe, Mohan; Mahalingam, S. [Department of Mechanical Engineering, University College London, London WC1E 7JE (United Kingdom); Bandara, I.M.C.C.D. [School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, 2 George Street, Brisbane 4001, QLD (Australia); Singh, Sanjleena [Central Analytical Research Facility, Institute of Future Environments, Queensland University of Technology, 2 George Street, Brisbane 4001, QLD (Australia)

2016-06-01

Preparation of hydroxyapatite coated custom-made metallic bone-implants is very important for the replacement of injured bones of the body. Furthermore, these bone-implants are more stable under the corrosive environment of the body and biocompatible than bone-implants made up of pure metals and metal alloys. Herein, we describe a novel, simple and low-cost technique to prepare biocompatible hydroxyapatite coated titanium metal (TiM) implants through growth of self-formed TiO{sub 2} thin-layer (SFTL) on TiM via a heat treatment process. SFTL acts as a surface binder of HA nanoparticles in order to produce HA coated implants. Colloidal HA nanorods prepared by a novel surfactant-assisted synthesis method, have been coated on SFTL via atomized spray pyrolysis (ASP) technique. The corrosion behavior of the bare and surface-modified TiM (SMTiM) in a simulated body fluid (SBF) medium is also studied. The highest corrosion rate is found to be for the bare TiM plate, but the corrosion rate has been reduced with the heat-treatment of TiM due to the formation of SFTL. The lowest corrosion rate is recorded for the implant prepared by heat treatment of TiM at 700 °C. The HA-coating further assists in the passivation of the TiM in the SBF medium. Both SMTiM and HA coated SMTiM are noncytotoxic against osteoblast-like (HOS) cells and are in high-bioactivity. The overall production process of bone-implant described in this paper is in high economic value. - Highlights: • Colloidal hydroxyapatite nanorods are prepared by a novel method. • Surfaces of titanium metal plates are modified by self-forming TiO{sub 2} thin-films. • Prostheses are prepared by coating hydroxyapatite on surface modified Ti metal. • Bioactivity and noncytotoxicity are increased with surface modifications.

Preparation of bone-implants by coating hydroxyapatite nanoparticles on self-formed titanium dioxide thin-layers on titanium metal surfaces

International Nuclear Information System (INIS)

Wijesinghe, W.P.S.L.; Mantilaka, M.M.M.G.P.G.; Chathuranga Senarathna, K.G.; Herath, H.M.T.U.; Premachandra, T.N.; Ranasinghe, C.S.K.; Rajapakse, R.P.V.J.; Rajapakse, R.M.G.; Edirisinghe, Mohan; Mahalingam, S.; Bandara, I.M.C.C.D.; Singh, Sanjleena

2016-01-01

Preparation of hydroxyapatite coated custom-made metallic bone-implants is very important for the replacement of injured bones of the body. Furthermore, these bone-implants are more stable under the corrosive environment of the body and biocompatible than bone-implants made up of pure metals and metal alloys. Herein, we describe a novel, simple and low-cost technique to prepare biocompatible hydroxyapatite coated titanium metal (TiM) implants through growth of self-formed TiO_2 thin-layer (SFTL) on TiM via a heat treatment process. SFTL acts as a surface binder of HA nanoparticles in order to produce HA coated implants. Colloidal HA nanorods prepared by a novel surfactant-assisted synthesis method, have been coated on SFTL via atomized spray pyrolysis (ASP) technique. The corrosion behavior of the bare and surface-modified TiM (SMTiM) in a simulated body fluid (SBF) medium is also studied. The highest corrosion rate is found to be for the bare TiM plate, but the corrosion rate has been reduced with the heat-treatment of TiM due to the formation of SFTL. The lowest corrosion rate is recorded for the implant prepared by heat treatment of TiM at 700 °C. The HA-coating further assists in the passivation of the TiM in the SBF medium. Both SMTiM and HA coated SMTiM are noncytotoxic against osteoblast-like (HOS) cells and are in high-bioactivity. The overall production process of bone-implant described in this paper is in high economic value. - Highlights: • Colloidal hydroxyapatite nanorods are prepared by a novel method. • Surfaces of titanium metal plates are modified by self-forming TiO_2 thin-films. • Prostheses are prepared by coating hydroxyapatite on surface modified Ti metal. • Bioactivity and noncytotoxicity are increased with surface modifications.

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

An analysis of the plasma impurity influx from alkali-metal coatings for fusion reactor applications

International Nuclear Information System (INIS)

DeWald, A.B.; Davidson, J.N.; Krauss, A.R.; Gruen, D.M.

1982-01-01

Recently, it has been proposed that alkali-metal covered surfaces be applied to magnetic fusion devices as a means of controlling plasma impurity contamination and shielding the substrate from erosion. Monolayer films of alkali metals have been shown to sputter primarily as ions under particle bombardment. Thus, it is thought that a sheath potential and/or magnetic fields encountered by a sputtered ion will return the ion to the surface without entering the plasma. In this paper, we investigate the net wall impurity influx associated with coatings which exhibit substantial secondary ion emission compared with those which sputter only as neutral atoms. Included in the analysis are sputtered substrate atoms. These are sometimes found to be a significant fraction of the total sputtering yield for low-Z alkali monolayers and affect the overall performance of such coatings. Estimates of the impurity influx made in the neighborhood of a sheath potential show that secondary-ion emitting coatings are effective as a means of inhibiting plasma impurity contamination and wall erosion. (orig.)

All-Solution-Processed, Ambient Method for ITO-Free, Roll-Coated Tandem Polymer Solar Cells using Solution- Processed Metal Films

DEFF Research Database (Denmark)

Angmo, Dechan; Dam, Henrik Friis; Andersen, Thomas Rieks

2014-01-01

A solution-processed silver film is employed in the processing of top-illuminated indium-tin-oxide (ITO)-free polymer solar cells in single- and double-junction (tandem) structures. The nontransparent silver film fully covers the substrate and serves as the bottom electrode whereas a PEDOT...... in terms of surface morphological and topographical properties and to ITO in terms of flexibility. The slot–die coated Ag film demonstrates extremely low roughness (a root-meansquare roughness of 3 nm was measured over 240_320 mm2 area), is highly conductive (

Glow discharge optical emission spectroscopy for accurate and well resolved analysis of coatings and thin films

KAUST Repository

Wilke, Marcus

2011-12-01

In the last years, glow discharge optical emission spectrometry (GDOES) gained more and more acceptance in the analysis of functional coatings. GDOES thereby represents an interesting alternative to common depth profiling techniques like AES and SIMS, based on its unique combination of high erosion rates and erosion depths, sensitivity, analysis of nonconductive layers and easy quantification even for light elements such as C, N, O and H. Starting with the fundamentals of GDOES, a short overview on new developments in instrument design for accurate and well resolved thin film analyses is presented. The article focuses on the analytical capabilities of glow discharge optical emission spectrometry in the analysis of metallic coatings and thin films. Results illustrating the high depth resolution, confirmation of stoichiometry, the detection of light elements in coatings as well as contamination on the surface or interfaces will be demonstrated by measurements of: a multilayer system Cr/Ti on silicon, interface contamination on silicon during deposition of aluminum, Al2O3-nanoparticle containing conversion coatings on zinc for corrosion resistance, Ti3SiC2 MAX-phase coatings by pulsed laser deposition and hydrogen detection in a V/Fe multilayer system. The selected examples illustrate that GDOES can be successfully adopted as an analytical tool in the development of new materials and coatings. A discussion of the results as well as of the limitations of GDOES is presented. © 2011 Elsevier B.V.

UV protective zinc oxide coating for biaxially oriented polypropylene packaging film by atomic layer deposition

Energy Technology Data Exchange (ETDEWEB)

Lahtinen, Kimmo, E-mail: kimmo.lahtinen@lut.fi [ASTRaL, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli (Finland); Kääriäinen, Tommi, E-mail: tommi.kaariainen@colorado.edu [ASTRaL, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli (Finland); Johansson, Petri, E-mail: petri.johansson@tut.fi [Paper Converting and Packaging Technology, Tampere University of Technology, P.O.Box 589, FI-33101 Tampere (Finland); Kotkamo, Sami, E-mail: sami.kotkamo@tut.fi [Paper Converting and Packaging Technology, Tampere University of Technology, P.O.Box 589, FI-33101 Tampere (Finland); Maydannik, Philipp, E-mail: philipp.maydannik@lut.fi [ASTRaL, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli (Finland); Seppänen, Tarja, E-mail: tarja.seppanen@lut.fi [ASTRaL, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli (Finland); Kuusipalo, Jurkka, E-mail: jurkka.kuusipalo@tut.fi [Paper Converting and Packaging Technology, Tampere University of Technology, P.O.Box 589, FI-33101 Tampere (Finland); Cameron, David C., E-mail: david.cameron@miktech.fi [ASTRaL, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli (Finland)

2014-11-03

Biaxially oriented polypropylene (BOPP) packaging film was coated with zinc oxide (ZnO) coatings by atomic layer deposition (ALD) in order to protect the film from UV degradation. The coatings were made at a process temperature of 100 °C using diethylzinc and water as zinc and oxygen precursors, respectively. The UV protective properties of the coatings were tested by using UV–VIS and infrared spectrometry, differential scanning calorimetry (DSC) and a mechanical strength tester, which characterised the tensile and elastic properties of the film. The results obtained with 36 and 67 nm ZnO coatings showed that the ZnO UV protective layer is able to provide a significant decrease in photodegradation of the BOPP film under UV exposure. While the uncoated BOPP film suffered a complete degradation after a 4-week UV exposure, the 67 nm ZnO coated BOPP film was able to preserve half of its original tensile strength and 1/3 of its elongation at break after a 6-week exposure period. The infrared analysis and DSC measurements further proved the UV protection of the ZnO coatings. The results show that a nanometre scale ZnO coating deposited by ALD is a promising option when a transparent UV protection layer is sought for polymer substrates. - Highlights: • Atomic layer deposited zinc oxide coatings were used as UV protection layers. • Biaxially oriented polypropylene (BOPP) film was well protected against UV light. • Formation of UV degradation products in BOPP was significantly reduced. • Mechanical properties of the UV exposed BOPP film were significantly improved.

Fabrication and Evaluation of One-Axis Oriented Lead Zirconate Titanate Films Using Metal-Oxide Nanosheet Interface Layer

Science.gov (United States)

Minemura, Yoshiki; Nagasaka, Kohei; Kiguchi, Takanori; Konno, Toyohiko J.; Funakubo, Hiroshi; Uchida, Hiroshi

2013-09-01

Nanosheet Ca2Nb3O20 (ns-CN) layers with pseudo-perovskite-type crystal configuration were applied on the surface of polycrystalline metal substrates to achieve preferential crystal orientation of Pb(Zr,Ti)O3 (PZT) films for the purpose of enhanced ferroelectricity comparable to that of epitaxial thin films. PZT films with tetragonal symmetry (Zr/Ti=0.40:0.60) were fabricated by chemical solution deposition (CSD) on ns-CN-buffered Inconel 625 and SUS 316L substrates, while ns-CN was applied on the the substrates by dip-coating. The preferential crystal growth on the ns-CN layer can be achieved by favorable lattice matching between (001)/(100)PZT and (001)ns-CN planes. The degree of (001) orientation was increased for PZT films on ns-CN/Inconel 625 and ns-CN/SUS 316L substrates, whereas randomly-oriented PZT films with a lower degree of (001) orientation were grown on bare and Inconel 625 films. Enhanced remanent polarization of 60 µC/cm2 was confirmed for the PZT films on ns-CN/metal substrates, ascribed to the preferential alignment of the polar [001] axis normal to the substrate surface, although it also suffered from higher coercive field above 500 kV/cm caused by PZT/metal interfacial reaction.

Thin films of mixed metal compounds

Science.gov (United States)

Mickelsen, Reid A.; Chen, Wen S.

1985-01-01

A compositionally uniform thin film of a mixed metal compound is formed by simultaneously evaporating a first metal compound and a second metal compound from independent sources. The mean free path between the vapor particles is reduced by a gas and the mixed vapors are deposited uniformly. The invention finds particular utility in forming thin film heterojunction solar cells.

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.

Formation of corrosion-resistant oxide film on uranium

International Nuclear Information System (INIS)

Petit, G.S.

1976-01-01

A vacuum heat-treatment method was developed for coating metallic uranium with an adherent protective film of uranium oxide. The film is prepared by vacuum heat-treating the metallic uranium at 625 0 C for 1 h while controlling the amount of oxygen being metered into the furnace. Uranium coupons with the protective film were exposed for several hundred hours in a corrosion test bath at 95 0 C and 100 percent RH without corroding. Film thicknesses ranging from 5 to 25 μm (0.0002 to 0.001 in.) were prepared and corrosion tested; the film thickness can be controlled to less than +-2.5 μm (+-0.0001 in.). The oxide film is hard, nonwetting, and very adherent. The resulting surface finish of the metal is equivalent to that of the original finish. The advantages of the oxide films over other protective coatings are given. 12 fig

PEEK (polyether-ether-ketone)-coated nitinol wire: Film stability for biocompatibility applications

Energy Technology Data Exchange (ETDEWEB)

Sheiko, Nataliia [Institut Charles Sadron, C.N.R.S. UPR 22, Université de Strasbourg, 23 rue du Loess, BP 84047, 67034 Strasbourg Cedex 2 (France); Kékicheff, Patrick, E-mail: patrick.kekicheff@ics-cnrs.unistra.fr [Institut Charles Sadron, C.N.R.S. UPR 22, Université de Strasbourg, 23 rue du Loess, BP 84047, 67034 Strasbourg Cedex 2 (France); Marie, Pascal; Schmutz, Marc; Jacomine, Leandro [Institut Charles Sadron, C.N.R.S. UPR 22, Université de Strasbourg, 23 rue du Loess, BP 84047, 67034 Strasbourg Cedex 2 (France); Perrin-Schmitt, Fabienne [Faculté de Médecine, INSERM, UMR-S 1121, “Biomaterials and Bioengineering”, Université de Strasbourg, 11 rue Humann, 67085 Strasbourg Cedex (France)

2016-12-15

Highlights: • A thin (12 μm) homogeneous PEEK film without any defects or voids is deposited on NiTi wires. • The coating remains stable in biological environment with negligible Ni ion release and no cytotoxicity. • Large pressure (>2 GPa) can only disrupt the coating film as shown by nanoscratch tests. • Coated spring wires sustain mechanical stress in continuous cycles of axial compression/stretching for >7 million cycles. - Abstract: High quality biocompatible poly-ether-ether-ketone (PEEK) coatings were produced on NiTi shape memory alloy wires using dipping deposition from colloidal aqueous PEEK dispersions after substrate surface treatment. The surface morphology and microstructure were investigated by Scanning Electron Microscopy at every step of the process from the as-received Nitinol substrate to the ultimate PEEK-coated NiTi wire. Nanoscratch tests were carried out to access the adhesive behavior of the polymer coated film to the NiTi. The results indicate that the optimum process conditions in cleaning, chemical etching, and electropolishing the NiTi, were the most important and determining parameters to be achieved. Thus, high quality PEEK coatings were obtained on NiTi wires, straight or curved (even with a U-shape) with a homogeneous microstructure along the wire length and a uniform thickness of 12 μm without any development of cracks or the presence of large voids. The biocompatibility of the PEEK coating film was checked in fibrobast cultured cells. The coating remains stable in biological environment with negligible Ni ion release, no cytotoxicity, and no delamination observed with time.

PEEK (polyether-ether-ketone)-coated nitinol wire: Film stability for biocompatibility applications

International Nuclear Information System (INIS)

Sheiko, Nataliia; Kékicheff, Patrick; Marie, Pascal; Schmutz, Marc; Jacomine, Leandro; Perrin-Schmitt, Fabienne

2016-01-01

Highlights: • A thin (12 μm) homogeneous PEEK film without any defects or voids is deposited on NiTi wires. • The coating remains stable in biological environment with negligible Ni ion release and no cytotoxicity. • Large pressure (>2 GPa) can only disrupt the coating film as shown by nanoscratch tests. • Coated spring wires sustain mechanical stress in continuous cycles of axial compression/stretching for >7 million cycles. - Abstract: High quality biocompatible poly-ether-ether-ketone (PEEK) coatings were produced on NiTi shape memory alloy wires using dipping deposition from colloidal aqueous PEEK dispersions after substrate surface treatment. The surface morphology and microstructure were investigated by Scanning Electron Microscopy at every step of the process from the as-received Nitinol substrate to the ultimate PEEK-coated NiTi wire. Nanoscratch tests were carried out to access the adhesive behavior of the polymer coated film to the NiTi. The results indicate that the optimum process conditions in cleaning, chemical etching, and electropolishing the NiTi, were the most important and determining parameters to be achieved. Thus, high quality PEEK coatings were obtained on NiTi wires, straight or curved (even with a U-shape) with a homogeneous microstructure along the wire length and a uniform thickness of 12 μm without any development of cracks or the presence of large voids. The biocompatibility of the PEEK coating film was checked in fibrobast cultured cells. The coating remains stable in biological environment with negligible Ni ion release, no cytotoxicity, and no delamination observed with time.

Synthesis and characterization of nanoporous strontium-doped lanthanum cobaltite thin film using metal organic chemical solution deposition

Energy Technology Data Exchange (ETDEWEB)

Park, Jun-Sik [Department of Mechanical Convergence Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Kim, Young-Beom, E-mail: ybkim@hanyang.ac.kr [Department of Mechanical Convergence Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Institute of Nano Science and Technology, Hanyang University, Seoul 133-791 (Korea, Republic of)

2016-01-29

By employing strontium as a dopant of lanthanum cobaltite (LaCoO{sub 3}), strontium-doped lanthanum cobaltite (La{sub 1−x}Sr{sub x}CoO{sub 3−δ}, LSC) thin film was fabricated using a metal organic chemical solution deposition (MOCSD) method. Lanthanum nitrate hexahydrate [La(NO{sub 3}){sub 3}6H{sub 2}O], strontium acetate [Sr(CH{sub 3}COO){sub 2}], and cobalt acetate tetrahydrate [Co(CH{sub 3}COO){sub 2}4H{sub 2}O] were used as precursors. The coating process was performed through a spin coating method on a substrate, which were then heat treated under various temperature conditions. Electrical properties, microstructures, and crystalline structures with respect to sintering temperature were analyzed. According to these analyses, the change in surface morphology, phase shift, and conductive properties were closely related, which could explain their respective behaviors. Furthermore, sintered strontium-doped lanthanum perovskite oxides showed various conductivities according to the amount of dopant. With the molar ratio of strontium that is stoichiometrically equivalent to lanthanum (La{sub 0.5}Sr{sub 0.5}CoO{sub 3−δ}) thin film showed the best conductivity in the sintering temperature range of 650–700 °C, with perovskite phases formed at this temperature condition. As the electrically conductive properties of the thin film are a function of thickness, the films were coated several times to a thickness of approximately 300 nm, with the lowest resistivity (approximately 9.06 × 10{sup −4} Ω cm) observed at the optimized sintering temperature and solution composition. - Highlights: • LSC thin film was fabricated by metal organic chemical solution deposition (MOCSD). • The film shows good agreement on the electrical conductivity of LSC by conventional methods. • The properties of LSC film are influenced by the surface morphology and crystalline phase. • Optimal molar ratio of strontium for the highest conductivity was investigated.

Freestanding films of crosslinked gold nanoparticles prepared via layer-by-layer spin-coating

Science.gov (United States)

Schlicke, Hendrik; Schröder, Jan H.; Trebbin, Martin; Petrov, Alexey; Ijeh, Michael; Weller, Horst; Vossmeyer, Tobias

2011-07-01

A new, extremely efficient method for the fabrication of films comprised of gold nanoparticles (GNPs) crosslinked by organic dithiols is presented in this paper. The method is based on layer-by-layer spin-coating of both components, GNPs and crosslinker, and enables the deposition of films several tens of nanometers in thickness within a few minutes. X-ray diffraction and conductance measurements reveal the proper adjustment concentration of the crosslinker solution of the critical is in order to prevent the destabilization and coalescence of particles. UV/vis spectroscopy, atomic force microscopy, and conductivity measurements indicate that films prepared via layer-by-layer spin-coating are of comparable quality to coatings prepared via laborious layer-by-layer self-assembly using immersion baths. Because spin-coated films are not bound chemically to the substrate, they can be lifted-off by alkaline underetching and transferred onto 3d-electrodes to produce electrically addressable, freely suspended films. Comparative measurements of the sheet resistances indicate that the transfer process does not compromise the film quality.

Freestanding films of crosslinked gold nanoparticles prepared via layer-by-layer spin-coating

International Nuclear Information System (INIS)

Schlicke, Hendrik; Schroeder, Jan H; Trebbin, Martin; Petrov, Alexey; Ijeh, Michael; Weller, Horst; Vossmeyer, Tobias

2011-01-01

A new, extremely efficient method for the fabrication of films comprised of gold nanoparticles (GNPs) crosslinked by organic dithiols is presented in this paper. The method is based on layer-by-layer spin-coating of both components, GNPs and crosslinker, and enables the deposition of films several tens of nanometers in thickness within a few minutes. X-ray diffraction and conductance measurements reveal the proper adjustment concentration of the crosslinker solution of the critical is in order to prevent the destabilization and coalescence of particles. UV/vis spectroscopy, atomic force microscopy, and conductivity measurements indicate that films prepared via layer-by-layer spin-coating are of comparable quality to coatings prepared via laborious layer-by-layer self-assembly using immersion baths. Because spin-coated films are not bound chemically to the substrate, they can be lifted-off by alkaline underetching and transferred onto 3d-electrodes to produce electrically addressable, freely suspended films. Comparative measurements of the sheet resistances indicate that the transfer process does not compromise the film quality.

Biomolecule-coated metal nanoparticles on titanium.

Science.gov (United States)

Christensen, Stephen L; Chatt, Amares; Zhang, Peng

2012-02-07

Immobilizations of nanoparticles and biomolecules on biocompatible substrates such as titanium are two promising approaches to bringing new functionalities to Ti-based biomaterials. Herein, we used a variety of X-ray spectroscopic techniques to study and better understand metal-thiolate interactions in biofunctionalized metal nanoparticle systems supported on Ti substrates. Using a facile one-step procedure, a series of Au nanoparticle samples with varied biomolecule coatings ((2-mercatopropionyl)glycine (MPG) and bovine serum albumin (BSA)) and biomolecule concentrations are prepared. Ag and Pd systems are also studied to observe change with varying metal composition. The structure and properties of these biomolecule-coated nanoparticles are investigated with scanning electron microscopy (SEM) and element-specific X-ray techniques, including extended X-ray absorption fine structure (Au L(3)-edge), X-ray absorption near-edge structure (Au L(3), Ag L(3), Pd L(3), and S K-edge), and X-ray photoelectron spectroscopy (Au 4f, Ag 3d, Pd 3d, and S 2p core level). It was found that, by comparison of SEM and X-ray spectroscopy results, the coating of metal nanoparticles with varying model biomolecule systems can have a significant effect on both surface coverage and organization. This work offers a facile chemical method for bio- and nanofunctionalization of Ti substrates as well as provides a physical picture of the structure and bonding of biocoated metal nanoparticles, which may lead to useful applications in orthopedics and biomedicine.

Thin-Film Coated Plastic Wrap for Food Packaging

Directory of Open Access Journals (Sweden)

Hsin-Yu Wu

2017-07-01

Full Text Available In this study, the antimicrobial property and food package capability of polymethylpentene (PMP substrate with silicon oxdie (SiOx and organic silicon (SiCxHy stacked layers deposited by an inductively coupled plasma chemical vapor deposition system were investigated. The experimental results show that the stacked pair number of SiOx/SiCxHy on PMP is limited to three pairs, beyond which the films will crack and cause package failure. The three-pair SiOx/SiCxHy on PMP shows a low water vapor transmission rate of 0.57 g/m2/day and a high water contact angle of 102°. Three-pair thin-film coated PMP demonstrates no microbe adhesion and exhibits antibacterial properties within 24 h. Food shelf life testing performed at 28 °C and 80% humidity reports that the three-pair thin-film coated PMP can enhance the food shelf-life to 120 h. The results indicate that the silicon-based thin film may be a promising material for antibacterial food packaging applications to extend the shelf-life of food products.

Investigation of metal coatings for the free electron laser

International Nuclear Information System (INIS)

Scott, M.L.; Arendt, P.N.; Springer, R.W.; Cordi, R.C.; McCreary, W.J.

1985-01-01

We are investigating the deposition and characteristics of metal coatings for use in environments such as the Free Electron Laser where the radiation resistance of metal coatings could prove to be of great benefit. We have concentrated our initial efforts on silver laminate coatings due to the high reflectance of silver at 1 micron wavelength. Our initial laminate coatings have utilized thin layers of titanium oxide to break up the columnar structure of the silver during electron-beam deposition on fused silica substrates. Our initial results on equal coating thickness samples indicate an improvement in damage threshold that ranges from 1.07 to 1.71 at 351 nm

Metal-enhanced fluorescence of mixed coumarin dyes by silver and gold nanoparticles: Towards plasmonic thin-film luminescent solar concentrator

Energy Technology Data Exchange (ETDEWEB)

El-Bashir, S.M., E-mail: elbashireg@yahoo.com [Department of Physics and Astronomy, Science College, King Saud University, Riyadh, KSA (Saudi Arabia); Department of Physics Faculty of Science, Benha University (Egypt); Barakat, F.M.; AlSalhi, M.S. [Department of Physics and Astronomy, Science College, King Saud University, Riyadh, KSA (Saudi Arabia)

2013-11-15

Poly(methyl methacrylate) (PMMA) nanocomposite films doped with mixed coumarin dyestuffs and noble metal nanoparticles (60 nm silver and 100 nm gold) were prepared by spin coating technique. The effect of silver and gold nanoparticles on the film properties was studied by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), transmission electron microscopy (TEM), scanning electron microscopy (SEM), UV–vis absorption and fluorescence spectroscopy measurements. DSC measurements indicated the increase of the glass transition temperature of the films by increasing nanogold concentration, recommending their promising thermal stability towards hot climates. It was found that the fluorescence signals of the mixed coumarin dyes were amplified by 5.4 and 7.15 folds as a result of metal enhanced fluorescence (MEF). The research outcomes offered a potential application of these films in solar energy conversion by plasmonic thin film luminescent solar concentrator (PTLSC). -- Graphical abstract: Plasmonic thin film luminescent solar concentrators. Highlights: • Metal enhanced fluorescence was achieved for mixed coumarin dyes doped in PMMA nanocomposite films. • The amplification of the fluorescence signals is dependent on the concentration of silver and gold nanoparticles. • These films is considered as potential candidates for plasmonic thin film luminescent solar concentrators (PTLSCs)

Antioxidant migration resistance of SiOx layer in SiOx/PLA coated film.

Science.gov (United States)

Huang, Chongxing; Zhao, Yuan; Su, Hongxia; Bei, Ronghua

2018-02-01

As novel materials for food contact packaging, inorganic silicon oxide (SiO x ) films are high barrier property materials that have been developed rapidly and have attracted the attention of many manufacturers. For the safe use of SiO x films for food packaging it is vital to study the interaction between SiO x layers and food contaminants, as well as the function of a SiO x barrier layer in antioxidant migration resistance. In this study, we deposited a SiO x layer on polylactic acid (PLA)-based films to prepare SiO x /PLA coated films by plasma-enhanced chemical vapour deposition. Additionally, we compared PLA-based films and SiO x /PLA coated films in terms of the migration of different antioxidants (e.g. t-butylhydroquinone [TBHQ], butylated hydroxyanisole [BHA], and butylated hydroxytoluene [BHT]) via specific migration experiments and then investigated the effects of a SiO x layer on antioxidant migration under different conditions. The results indicate that antioxidant migration from SiO x /PLA coated films is similar to that for PLA-based films: with increase of temperature, decrease of food simulant polarity, and increase of single-sided contact time, the antioxidant migration rate and amount in SiO x /PLA coated films increase. The SiO x barrier layer significantly reduced the amount of migration of antioxidants with small and similar molecular weights and similar physical and chemical properties, while the degree of migration blocking was not significantly different among the studied antioxidants. However, the migration was affected by temperature and food simulant. Depending on the food simulants considered, the migration amount in SiO x /PLA coated films was reduced compared with that in PLA-based films by 42-46%, 44-47%, and 44-46% for TBHQ, BHA, and BHT, respectively.

Metal matrix coated fiber composites and the methods of manufacturing such composites

Science.gov (United States)

Weeks, J.K. Jr.; Gensse, C.

1993-09-14

A fiber coating which allows ceramic or metal fibers to be wetted by molten metals is disclosed. The coating inhibits degradation of the physical properties caused by chemical reaction between the fiber and the coating itself or between the fiber and the metal matrix. The fiber coating preferably includes at least a wetting layer, and in some applications, a wetting layer and a barrier layer between the fiber and the wetting layer. The wetting layer promotes fiber wetting by the metal matrix. The barrier layer inhibits fiber degradation. The fiber coating permits the fibers to be infiltrated with the metal matrix resulting in composites having unique properties not obtainable in pure materials. 8 figures.

Antimicrobial edible coatings and films from micro-emulsions and their food applications.

Science.gov (United States)

Guo, Mingming; Yadav, Madhav P; Jin, Tony Z

2017-12-18

This study focused on the use of antimicrobial edible coatings and films from micro-emulsions to reduce populations of foodborne pathogens in foods. Corn-Bio-fiber gum (C-BFG) was used as an emulsifier with chitosan. Allyl isothiocyanate (AIT) and lauric arginate ester (LAE) served as antimicrobials. Micro-emulsions were obtained from a solution consisting of 1% chitosan, 0.5% C-BFG, and 1-4% AIT or LAE which was subject to high pressure homogenization (HPH) processing at 138MPa for 3cycles. Coatings and films produced from the micro-emulsions had micro-pores with sizes ranging from 100 to 300nm and micro-channels that hold antimicrobials effectively and facilitate the release of antimicrobials from the center to the surface of the films or coatings, thus enhancing their antimicrobial efficacy. The coatings and films with 1% AIT reduced populations of Listeria innocua by over 5, 2, and 3 log CFU in culture medium (Tryptic soy broth, TSB), ready-to-eat meat, and strawberries, respectively. The coatings and films with 1% LAE reduced populations of Escherichia coli O157:H7 and Salmonella spp. by over 5 and 2 log CFU in TSB and strawberries, respectively. This study provides an innovative approach for the development of effective antimicrobial materials to reduce food borne pathogenic contaminants on ready-to-eat meat, strawberries, or other food. Published by Elsevier B.V.

Nanocomposites biodegradable coating on BOPET films to enhance hot seal strength properties

International Nuclear Information System (INIS)

Barbaro, G.; Galdi, M. R.; Di Maio, L.; Incarnato, L.

2015-01-01

The coating technology is a strategic solution to improve the properties of flexible packaging films. Indeed, additional functional layers are often designed and added as coating on the substrate, in order to improve the characteristic of the flexible packaging and to meet the requirements for the desired gas or vapour barrier, for adhesion and sealing, or for improving the film printability, its aesthetics and durability. Moreover, this technology allows to functionalize a polymeric substrate applying materials with different chemistry, rheology, thermal and structural characteristics. BOPET films are widely used for food packaging applications thanks to their good gas barrier and mechanical properties, high transparency and for the excellent printability. In regard to sealing performance, BOPET films show poor sealing properties so they are mostly submitted to lamination processes with polyethylene. Nevertheless, this solution compromises the PET recyclability and influences the gas permeability of the multilayer PET based structures. The aim of this work is to investigate on the effect of nanocomposite biodegradable coatings for BOPET substrates in enhancing the heat sealing strength of eco-compatible PET/PLA films. At this regards, different percentages of Cloisite C30B (0%, 2% and 4% wt/wt ) have been added to PLA by solution intercalation technique and the nanocomposite biodegradable materials produced have been applied on BOPET commercial films by casting. The BOPET coated films have been characterized in order to evaluate the heat sealing strength and the mechanical, gas permeability and surface properties. The results have shown that the addition of nanoclay in PLA coating significantly enhance the hot tack properties of the PET/PLA system produced, while the oxygen and water vapour permeability are slightly increased if compared to pure BOPET films

Nanocomposites biodegradable coating on BOPET films to enhance hot seal strength properties

Energy Technology Data Exchange (ETDEWEB)

Barbaro, G., E-mail: giovannibarbaro@email.it; Galdi, M. R., E-mail: mrgaldi@unisa.it; Di Maio, L., E-mail: ldimaio@unisa.it; Incarnato, L., E-mail: lincarnato@unisa.it [Industrial Engineering Department, University of Salerno, Via Giovanni Paolo II 132, 84084 Fisciano (Italy)

2015-12-17

The coating technology is a strategic solution to improve the properties of flexible packaging films. Indeed, additional functional layers are often designed and added as coating on the substrate, in order to improve the characteristic of the flexible packaging and to meet the requirements for the desired gas or vapour barrier, for adhesion and sealing, or for improving the film printability, its aesthetics and durability. Moreover, this technology allows to functionalize a polymeric substrate applying materials with different chemistry, rheology, thermal and structural characteristics. BOPET films are widely used for food packaging applications thanks to their good gas barrier and mechanical properties, high transparency and for the excellent printability. In regard to sealing performance, BOPET films show poor sealing properties so they are mostly submitted to lamination processes with polyethylene. Nevertheless, this solution compromises the PET recyclability and influences the gas permeability of the multilayer PET based structures. The aim of this work is to investigate on the effect of nanocomposite biodegradable coatings for BOPET substrates in enhancing the heat sealing strength of eco-compatible PET/PLA films. At this regards, different percentages of Cloisite C30B (0%, 2% and 4%{sub wt/wt}) have been added to PLA by solution intercalation technique and the nanocomposite biodegradable materials produced have been applied on BOPET commercial films by casting. The BOPET coated films have been characterized in order to evaluate the heat sealing strength and the mechanical, gas permeability and surface properties. The results have shown that the addition of nanoclay in PLA coating significantly enhance the hot tack properties of the PET/PLA system produced, while the oxygen and water vapour permeability are slightly increased if compared to pure BOPET films.

Nanocomposites biodegradable coating on BOPET films to enhance hot seal strength properties

Science.gov (United States)

Barbaro, G.; Galdi, M. R.; Di Maio, L.; Incarnato, L.

2015-12-01

The coating technology is a strategic solution to improve the properties of flexible packaging films. Indeed, additional functional layers are often designed and added as coating on the substrate, in order to improve the characteristic of the flexible packaging and to meet the requirements for the desired gas or vapour barrier, for adhesion and sealing, or for improving the film printability, its aesthetics and durability. Moreover, this technology allows to functionalize a polymeric substrate applying materials with different chemistry, rheology, thermal and structural characteristics. BOPET films are widely used for food packaging applications thanks to their good gas barrier and mechanical properties, high transparency and for the excellent printability. In regard to sealing performance, BOPET films show poor sealing properties so they are mostly submitted to lamination processes with polyethylene. Nevertheless, this solution compromises the PET recyclability and influences the gas permeability of the multilayer PET based structures. The aim of this work is to investigate on the effect of nanocomposite biodegradable coatings for BOPET substrates in enhancing the heat sealing strength of eco-compatible PET/PLA films. At this regards, different percentages of Cloisite C30B (0%, 2% and 4%wt/wt) have been added to PLA by solution intercalation technique and the nanocomposite biodegradable materials produced have been applied on BOPET commercial films by casting. The BOPET coated films have been characterized in order to evaluate the heat sealing strength and the mechanical, gas permeability and surface properties. The results have shown that the addition of nanoclay in PLA coating significantly enhance the hot tack properties of the PET/PLA system produced, while the oxygen and water vapour permeability are slightly increased if compared to pure BOPET films.

Degradation of zinc oxide thin films in aqueous environment. Pt. II. Coated films

Energy Technology Data Exchange (ETDEWEB)

Rosa, L. de; Mitton, D.B.; Monetta, T.; Bellucci, F. [Naples Univ. (Italy). Dept. of Materials and Production Engineering; Springer, J. [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Stuttgart (Germany)

2001-12-01

cn Part I of this research, the degradation mechanism of two different bare ZnO thin films was assessed. Degradation of the electrical properties of ZnO as well as changes in morphology were observed for both films. In the current paper, the degradation of zinc oxide thin films coated with protective acrylic paint is addressed during exposure to (i) an aqueous 3.5% NaCl solution at 85 C and (ii) a standard damp heat test at 85% R.H. and 85 C. Electrical and electrochemical techniques were employed to monitor zinc oxide degradation during exposure to the test environments. Electrochemical Impedance Spectroscopy was employed to investigate the delamination phenomena at the ZnO/coating interface and a simple equivalent circuit was developed to quantitatively measure the delamination ratio. The effect of different silane based adhesion promoters (glycidil-oxypropyl-trimethoxy-silane and aminopropyl-trimethoxy-silane) was also investigated. (orig.)

Electrosprayed Metal Oxide Semiconductor Films for Sensitive and Selective Detection of Hydrogen Sulfide

Directory of Open Access Journals (Sweden)

Maryam Siadat

2009-11-01

Full Text Available Semiconductor metal oxide films of copper-doped tin oxide (Cu-SnO2, tungsten oxide (WO3 and indium oxide (In2O3 were deposited on a platinum coated alumina substrate employing the electrostatic spray deposition technique (ESD. The morphology studied with scanning electron microscopy (SEM and atomic force microscopy (AFM shows porous homogeneous films comprising uniformly distributed aggregates of nano particles. The X-ray diffraction technique (XRD proves the formation of crystalline phases with no impurities. Besides, the Raman cartographies provided information about the structural homogeneity. Some of the films are highly sensitive to low concentrations of H2S (10 ppm at low operating temperatures (100 and 200 °C and the best response in terms of Rair/Rgas is given by Cu-SnO2 films (2500 followed by WO3 (1200 and In2O3 (75. Moreover, all the films exhibit no cross-sensitivity to other reducing (SO2 or oxidizing (NO2 gases.

Thin Film Coatings for Suppressing Electron Multipacting in Particle Accelerators

CERN Document Server

Costa Pinto, P; Chiggiato, P; Neupert, H; Shaposhnikova, E N; Taborelli, M; Vollenberg, W; Yin Vallgren, C

2011-01-01

Thin film coatings are an effective way for suppressing electron multipacting in particle accelerators. For bakeable beam pipes, the TiZrV Non Evaporable Getter (NEG) developed at CERN can provide a Secondary Electron Yield (SEY) of 1.1 after activation at 180oC (24h). The coating process was implemented in large scale to coat the long straight sections and the experimental beam pipes for the Large Hadron Collider (LHC). For non bakeable beam pipes, as those of the Super Proton Synchrotron (SPS), CERN started a campaign to develop a coating having a low SEY without need of in situ heating. Magnetron sputtered carbon thin films have shown SEY of 1 with marginal deterioration when exposed in air for months. This material is now being tested in both laboratory and accelerator environment. At CERN’s SPS, tests with electron cloud monitors attached to carbon coated chambers show no degradation of the coating after two years of operation interleaved with a total of 3 months of air exposure during shutdown periods...

Filmes de titânio-silício preparados por "spin" e "dip-coating"

Directory of Open Access Journals (Sweden)

Nassar Eduardo J.

2003-01-01

Full Text Available The conditions for the preparation of luminescent materials, consisting of Eu3+ ions entrapped in a titanium matrix, in the forma of a thin film, using the sol-gel process, are described. The films were obtained from sols prepared with TEOS and TEOT, in the presence of acetylacetone as the hidrolysis-retarding agent, using the dip-coating and spin-coating techniques. The influence of these techniques on the films based on titanium and silicon are presented. The Eu3+ was used as a luminescent probe. The films have been characterized by luminescence, reflection and transmittance. The thickness of the films could be related to the preparation procedure. Transparent thin films have been prepared by dip-coating technique.

Functionalized Antimicrobial Composite Thin Films Printing for Stainless Steel Implant Coatings

Directory of Open Access Journals (Sweden)

Laura Floroian

2016-06-01

Full Text Available In this work we try to address the large interest existing nowadays in the better understanding of the interaction between microbial biofilms and metallic implants. Our aimed was to identify a new preventive strategy to control drug release, biofilm formation and contamination of medical devices with microbes. The transfer and printing of novel bioactive glass-polymer-antibiotic composites by Matrix-Assisted Pulsed Laser Evaporation into uniform thin films onto 316 L stainless steel substrates of the type used in implants are reported. The targets were prepared by freezing in liquid nitrogen mixtures containing polymer and antibiotic reinforced with bioglass powder. The cryogenic targets were submitted to multipulse evaporation by irradiation with an UV KrF* (λ = 248 nm, τFWHM ≤ 25 ns excimer laser source. The prepared structures were analyzed by infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy and profilometry, before and after immersion in physiological fluids. The bioactivity and the release of the antibiotic have been evaluated. We showed that the incorporated antibiotic underwent a gradually dissolution in physiological fluids thus supporting a high local treatment efficiency. Electrochemical measurements including linear sweep voltammetry and impedance spectroscopy studies were carried out to investigate the corrosion resistance of the coatings in physiological environments. The in vitro biocompatibility assay using the MG63 mammalian cell line revealed that the obtained nanostructured composite films are non-cytotoxic. The antimicrobial effect of the coatings was tested against Staphylococcus aureus and Escherichia coli strains, usually present in implant-associated infections. An anti-biofilm activity was evidenced, stronger against E. coli than the S. aureus strain. The results proved that the applied method allows for the fabrication of implantable biomaterials which shield metal ion release

Functionalized Antimicrobial Composite Thin Films Printing for Stainless Steel Implant Coatings.

Science.gov (United States)

Floroian, Laura; Ristoscu, Carmen; Mihailescu, Natalia; Negut, Irina; Badea, Mihaela; Ursutiu, Doru; Chifiriuc, Mariana Carmen; Urzica, Iuliana; Dyia, Hussien Mohammed; Bleotu, Coralia; Mihailescu, Ion N

2016-06-09

In this work we try to address the large interest existing nowadays in the better understanding of the interaction between microbial biofilms and metallic implants. Our aimed was to identify a new preventive strategy to control drug release, biofilm formation and contamination of medical devices with microbes. The transfer and printing of novel bioactive glass-polymer-antibiotic composites by Matrix-Assisted Pulsed Laser Evaporation into uniform thin films onto 316 L stainless steel substrates of the type used in implants are reported. The targets were prepared by freezing in liquid nitrogen mixtures containing polymer and antibiotic reinforced with bioglass powder. The cryogenic targets were submitted to multipulse evaporation by irradiation with an UV KrF* (λ = 248 nm, τFWHM ≤ 25 ns) excimer laser source. The prepared structures were analyzed by infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy and profilometry, before and after immersion in physiological fluids. The bioactivity and the release of the antibiotic have been evaluated. We showed that the incorporated antibiotic underwent a gradually dissolution in physiological fluids thus supporting a high local treatment efficiency. Electrochemical measurements including linear sweep voltammetry and impedance spectroscopy studies were carried out to investigate the corrosion resistance of the coatings in physiological environments. The in vitro biocompatibility assay using the MG63 mammalian cell line revealed that the obtained nanostructured composite films are non-cytotoxic. The antimicrobial effect of the coatings was tested against Staphylococcus aureus and Escherichia coli strains, usually present in implant-associated infections. An anti-biofilm activity was evidenced, stronger against E. coli than the S. aureus strain. The results proved that the applied method allows for the fabrication of implantable biomaterials which shield metal ion release and possess

Imaging optical fields below metal films and metal-dielectric waveguides by a scanning microscope

Science.gov (United States)

Zhu, Liangfu; Wang, Yong; Zhang, Douguo; Wang, Ruxue; Qiu, Dong; Wang, Pei; Ming, Hai; Badugu, Ramachandram; Rosenfeld, Mary; Lakowicz, Joseph R.

2017-09-01

Laser scanning confocal fluorescence microscopy (LSCM) is now an important method for tissue and cell imaging when the samples are located on the surfaces of glass slides. In the past decade, there has been extensive development of nano-optical structures that display unique effects on incident and transmitted light, which will be used with novel configurations for medical and consumer products. For these applications, it is necessary to characterize the light distribution within short distances from the structures for efficient detection and elimination of bulky optical components. These devices will minimize or possibly eliminate the need for free-space light propagation outside of the device itself. We describe the use of the scanning function of a LSCM to obtain 3D images of the light intensities below the surface of nano-optical structures. More specifically, we image the spatial distributions inside the substrate of fluorescence emission coupled to waveguide modes after it leaks through thin metal films or dielectric-coated metal films. The observed spatial distribution were in general agreement with far-field calculations, but the scanning images also revealed light intensities at angles not observed with classical back focal plane imaging. Knowledge of the subsurface optical intensities will be crucial in the combination of nano-optical structures with rapidly evolving imaging detectors.

Transparent nanocrystalline ZnO films prepared by spin coating

Energy Technology Data Exchange (ETDEWEB)

Berber, M. [SusTech GmbH and Co. KG, Petersenstr. 20, 64287 Darmstadt, Hessen (Germany)]. E-mail: mete.berber@sustech.de; Bulto, V. [SusTech GmbH and Co. KG, Petersenstr. 20, 64287 Darmstadt, Hessen (Germany); Kliss, R. [SusTech GmbH and Co. KG, Petersenstr. 20, 64287 Darmstadt, Hessen (Germany); Hahn, H. [SusTech GmbH and Co. KG, Petersenstr. 20, 64287 Darmstadt, Hessen (Germany); Forschungszentrum Karlsruhe, Institute for Nanotechnology, Postfach 3640, 76021 Karlsruhe (Germany); Joint Research Laboratory Nanomaterials, TU Darmstadt, Institute of Materials Science, Petersenstr. 23, 64287 Darmstadt (Germany)

2005-09-15

Dispersions of zinc oxide nanoparticles synthesized by the electrochemical deposition under oxidizing conditions process with organic surfactants, were spin coated on glass substrates. After sintering, the microstructure, surface morphology, and electro-optical properties of the transparent nanocrystalline zinc oxide films have been investigated for different coating thicknesses and organic solvents.

Transparent nanocrystalline ZnO films prepared by spin coating

International Nuclear Information System (INIS)

Berber, M.; Bulto, V.; Kliss, R.; Hahn, H.

2005-01-01

Dispersions of zinc oxide nanoparticles synthesized by the electrochemical deposition under oxidizing conditions process with organic surfactants, were spin coated on glass substrates. After sintering, the microstructure, surface morphology, and electro-optical properties of the transparent nanocrystalline zinc oxide films have been investigated for different coating thicknesses and organic solvents

Growth and BZO-doping of the nanostructured YBCO thin films on buffered metal substrates

DEFF Research Database (Denmark)

Huhtinen, H.; Irjala, M.; Paturi, P.

2010-01-01

The growth of the nanostructured YBa2Cu3O6+x (YBCO) films is investigated for the first time on biaxially textured NiW substrates used in coated conductor technology. The optimization process of superconducting layers is made in wide magnetic field and temperature range in order to understand...... the vortex pinning structure and mechanism in our films prepared from nanostructured material. Structural analysis shows that growth mechanism in YBCO films grown on NiW is completely different when compared to YBCO on STO. Films on NiW are much rougher, there is huge in-plane variation of YBCO crystals...... and moreover out-of-plane long range lattice ordering is greatly reduced. Magnetic measurements demonstrate that jc in films grown on NiW is higher in high magnetic fields and low temperatures. This effect is connected to the amount of pinning centres observed in films on metal substrates which are effective...

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.)

Corrosion properties of the Mg alloy coated with polypyrrole films

International Nuclear Information System (INIS)

Grubač, Zoran; Rončević, Ivana Škugor; Metikoš-Huković, Mirjana

2016-01-01

Highlights: • Electropolymerization of pyrrole on Mg-alloy surface in presence of salicylate. • Salicylate dual role in PPy deposition: passivation and electron transfer mediation. • Redox potential of salicylate corresponds to potential of PPy nucleation. • EIS and polarization corrosion studies of PPy coated Mg-alloy in Hanks’ solution. • Polypyrrole significantly slowdown Mg alloy corrosion in Hanks’ solution. - Abstract: In the present study the reactive surface of Mg alloy was coated with the nontoxic biocompatible polypyrrole (PPy) film synthesized by electrochemical oxidation from an aqueous salicylate solution. Salicylate ions prevent Mg dissolution and act as an electron transfer mediator during the PPy film nucleation, formation and growth on the alloy surface. Kinetics of the pyrrole polymerization as well as corrosion resistance of the PPy coated Mg alloy in the Hanks’ solution were investigated using dc electrochemical methods and electrochemical impedance spectroscopy (EIS). Characterization of the surface film was performed by optical and Fourier transform infrared spectroscopy (FTIR).

Effect of nano-silver hydrogel coating film on deep partial thickness scald model of rabbit

Directory of Open Access Journals (Sweden)

Peng Xi

2018-05-01

Full Text Available Objective: Observing the effect of nano-silver hydrogel coating film on deep partial thickness scald model of rabbit. Method: We prepared boiling water scalded rabbits with deep II degree scald models and applied high, medium and low doses of nano-silver hydrogel coating film for different time and area. Then we compared the difference of burned paper weight before administration and after administration model burns, burn local skin irritation points infection, skin crusting and scabs from the time, and the impact of local skin tissue morphology. Result: Rabbits deep II degree burn model successful modeling; on day 12, 18, high, medium and low doses of nano-silver hydrogel coating film significantly reduced skin irritation of rabbits infected with the integral value (P < 0.01, P < 0.05; high, medium and low doses of nano-silver hydrogel coating film group significantly decreased skin irritation, infection integral value (P < 0.01, P < 0.05; high, medium and low doses of nano-silver hydrogel coating film significantly reduced film rabbits’ scalded skin crusting time (P < 0.01, significantly shortened the rabbit skin burns from the scab time (P < 0.01, and significantly improved the treatment of skin diseases in rabbits scald model change (P < 0.01, P < 0.05. Conclusion: The nano-silver hydrogel coating film on the deep partial thickness burns has a significant therapeutic effect; external use has a significant role in wound healing. Keywords: Nano-silver hydrogel coating film, Deep degree burns, Topical, Rabbits

Co3O4 protective coatings prepared by Pulsed Injection Metal Organic Chemical Vapour Deposition

DEFF Research Database (Denmark)

Burriel, M.; Garcia, G.; Santiso, J.

2005-01-01

of deposition temperature. Pure Co3O4 spinel structure was found for deposition temperatures ranging from 360 to 540 degreesC. The optimum experimental parameters to prepare dense layers with a high growth rate were determined and used to prepare corrosion protective coatings for Fe-22Cr metallic interconnects......Cobalt oxide films were grown by Pulsed Injection Metal Organic Chemical Vapour Deposition (PI-MOCVD) using Co(acac)(3) (acac=acetylacetonate) precursor dissolved in toluene. The structure, morphology and growth rate of the layers deposited on silicon substrates were studied as a function......, to be used in Intermediate Temperature Solid Oxide Fuel Cells. (C) 2004 Elsevier B.V. All rights reserved....

Recent innovations in the area of edible films and coatings.

Science.gov (United States)

Maftoonazad, Neda; Badii, Fojan; Shahamirian, Maryam

2013-12-01

Edible films/coatings have been considered as one of the potential technologies that can be used to increase the storability of foods and to improve the existent packaging technology, helping to ensure the microbial safety and the preservation of food from the influence of external factors. Innovations constantly appear in food packaging, always aiming at creating a more efficient quality preservation system while improving foods' attractiveness and marketability. The utilization of renewable sources for packaging materials, such as hydrocolloids and lipids from biological origin, is one the main trends of the industry. These films should have acceptable sensory characteristics, appropriate barrier properties (CO2, O2, water, oil), microbial, biochemical and physicochemical stability, they should be safe, and produced by simple technology in low cost. Also they can act as effective carrier for antioxidant, flavor, color and nutritional or anti-microbial additives. Nowadays, a great discussion exists about the potential applications of edible films/coatings on food products. The general trend is to find the correct combination between the food product and the edible film/coating, which will ensure the success of the technology.

Antimicrobial edible films and coatings for fresh and minimally processed fruits and vegetables: a review.

Science.gov (United States)

Valencia-Chamorro, Silvia A; Palou, Lluís; Del Río, Miguel A; Pérez-Gago, María B

2011-01-01

The use of edible films and coatings is an environmentally friendly technology that offers substantial advantages for shelf-life increase of many food products including fruits and vegetables. The development of new natural edible films and coatings with the addition of antimicrobial compounds to preserve fresh and minimally processed fruits and vegetables is a technological challenge for the industry and a very active research field worldwide. Antimicrobial agents have been successfully added to edible composite films and coatings based on polysaccharides or proteins such as starch, cellulose derivatives, chitosan, alginate, fruit puree, whey protein isolated, soy protein, egg albumen, wheat gluten, or sodium caseinate. This paper reviews the development of edible films and coatings with antimicrobial activity, typically through the incorporation of antimicrobial food additives as ingredients, the effect of these edible films on the control of target microorganisms, the influence of antimicrobial agents on mechanical and barrier properties of stand-alone edible films, and the effect of the application of antimicrobial edible coatings on the quality of fresh and fresh-cut fruits and vegetables.

Corrosion resistant coatings for uranium and uranium alloys

International Nuclear Information System (INIS)

Weirick, L.J.; Lynch, C.T.

1977-01-01

Coatings to prevent the corrosion of uranium and uranium alloys are considered in two military applications: kinetic energy penetrators and aircraft counterweights. This study, which evaluated organic films and metallic coatings, demonstrated that the two most promising coatings are based on an electrodeposited nickel system and a galvanized zinc system

Advanced fabrication method for the preparation of MOF thin films: Liquid-phase epitaxy approach meets spin coating method.

KAUST Repository

Chernikova, Valeriya

2016-07-14

Here we report a new and advanced method for the fabrication of highly oriented/polycrystalline metal-organic framework (MOF) thin films. Building on the attractive features of the liquid-phase epitaxy (LPE) approach, a facile spin coating method was implemented to generate MOF thin films in a high-throughput fashion. Advantageously, this approach offers a great prospective to cost-effectively construct thin-films with a significantly shortened preparation time and a lessened chemicals and solvents consumption, as compared to the conventional LPE-process. Certainly, this new spin-coating approach has been implemented successfully to construct various MOF thin films, ranging in thickness from a few micrometers down to the nanometer scale, spanning 2-D and 3-D benchmark MOF materials including Cu2(bdc)2•xH2O, Zn2(bdc)2•xH2O, HKUST-1 and ZIF-8. This method was appraised and proved effective on a variety of substrates comprising functionalized gold, silicon, glass, porous stainless steel and aluminum oxide. The facile, high-throughput and cost-effective nature of this approach, coupled with the successful thin film growth and substrate versatility, represents the next generation of methods for MOF thin film fabrication. Thereby paving the way for these unique MOF materials to address a wide range of challenges in the areas of sensing devices and membrane technology.

Indium tin oxide films prepared by atmospheric plasma annealing and their semiconductor-metal conductivity transition around room temperature

International Nuclear Information System (INIS)

Li Yali; Li Chunyang; He Deyan; Li Junshuai

2009-01-01

We report the synthesis of indium tin oxide (ITO) films using the atmospheric plasma annealing (APA) technique combined with the spin-coating method. The ITO film with a low resistivity of ∼4.6 x 10 -4 Ω cm and a high visible light transmittance, above 85%, was achieved. Hall measurement indicates that compared with the optimized ITO films deposited by magnetron sputtering, the above-mentioned ITO film has a higher carrier concentration of ∼1.21 x 10 21 cm -3 and a lower mobility of ∼11.4 cm 2 V -1 s -1 . More interestingly, these electrical characteristics result in the semiconductor-metal conductivity transition around room temperature for the ITO films prepared by APA.

The Tribological Behaviors of Three Films Coated on Biomedical Titanium Alloy by Chemical Vapor Deposition

Science.gov (United States)

Wang, Song; Liao, Zhenhua; Liu, Yuhong; Liu, Weiqiang

2015-11-01

Three thin films (DLC, a-C, and TiN) were performed on Ti6Al4V by chemical vapor deposition. Carbon ion implantation was pretreated for DLC and a-C films while Ti transition layer was pretreated for TiN film to strengthen the bonding strength. X-ray diffraction, Raman measurement, nano-hardness and nano-scratch tester, and cross-section etching by FIB method were used to analyze film characteristics. Tribological behaviors of these coatings were studied by articulation with both ZrO2 and UHMWPE balls using ball-on-disk sliding. The thickness values reached ~0.46, ~0.33, and ~1.67 μm for DLC, a-C, and TiN film, respectively. Nano-hardness of the coatings compared with that of untreated and bonding strength (critical load in nano-scratch test) values of composite coatings compared with that of monolayer film all increased significantly, respectively. Under destructive test (ZrO2 ball conterface) in bovine serum lubrication, TiN coating revealed the best wear resistance while DLC showed the worst. Film failure was mainly attributed to the plowing by hard ZrO2 ball characterized by abrasive and adhesive wear. Under normal test (UHMWPE ball conterface), all coatings showed significant improvement in wear resistance both in dry sliding and bovine serum lubrication. Both DLC and a-C films showed less surface damage than TiN film due to the self-lubricating phenomenon in dry sliding. TiN film showed the largest friction coefficient both in destructive and normal tests, devoting to the big TiN grains thus leading to much rougher surface and then a higher value. The self-lubricating film formed on DLC and a-C coating could also decrease their friction coefficients. The results indicated that three coatings revealed different wear mechanisms, and thick DLC or a-C film was more promising in application in lower stress conditions such as artificial cervical disk.

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

Visible tunable lighting system based on polymer composites embedding ZnO and metallic clusters: from colloids to thin films

Science.gov (United States)

Truong, Thai Giang; Dierre, Benjamin; Grasset, Fabien; Saito, Noriko; Saito, Norio; Nguyen, Thi Kim Ngan; Takahashi, Kohsei; Uchikoshi, Tetsuo; Amela-Cortes, Marian; Molard, Yann; Cordier, Stéphane; Ohashi, Naoki

2016-01-01

The development of phosphor devices free of heavy metal or rare earth elements is an important issue for environmental reasons and energy efficiency. Different mixtures of ZnO nanocrystals with Cs2Mo6I8(OOC2F5)6 cluster compound (CMIF) dispersed into polyvinylpyrrolidone matrix have been prepared by very simple and low cost solution chemistry. The resulting solutions have been used to fabricate highly transparent and luminescent films by dip coating free of heavy metal or rare earth elements. The luminescence properties of solution and dip-coated films were investigated. The luminescence of such a system is strongly dependent on the ratios between ZnO and CMIF amounts, the excitation wavelength and the nature of the system. By varying these two parameters (ratio and wavelength), a large variety of colors, from blue to red as well as white, can be achieved. In addition, differences in the luminescence properties have been observed between solutions and thin films as well as changes of CMIF emission band maximum wavelength. This may suggest some possible interactions between the different luminophore centers, such as energy transfer or ligands exchange on the Mo6 clusters.

Development of Anti-Insect Microencapsulated Polypropylene Films Using a Large Scale Film Coating System.

Science.gov (United States)

Song, Ah Young; Choi, Ha Young; Lee, Eun Song; Han, Jaejoon; Min, Sea C

2018-04-01

Films containing microencapsulated cinnamon oil (CO) were developed using a large-scale production system to protect against the Indian meal moth (Plodia interpunctella). CO at concentrations of 0%, 0.8%, or 1.7% (w/w ink mixture) was microencapsulated with polyvinyl alcohol. The microencapsulated CO emulsion was mixed with ink (47% or 59%, w/w) and thinner (20% or 25%, w/w) and coated on polypropylene (PP) films. The PP film was then laminated with a low-density polyethylene (LDPE) film on the coated side. The film with microencapsulated CO at 1.7% repelled P. interpunctella most effectively. Microencapsulation did not negatively affect insect repelling activity. The release rate of cinnamaldehyde, an active repellent, was lower when CO was microencapsulated than that in the absence of microencapsulation. Thermogravimetric analysis exhibited that microencapsulation prevented the volatilization of CO. The tensile strength, percentage elongation at break, elastic modulus, and water vapor permeability of the films indicated that microencapsulation did not affect the tensile and moisture barrier properties (P > 0.05). The results of this study suggest that effective films for the prevention of Indian meal moth invasion can be produced by the microencapsulation of CO using a large-scale film production system. Low-density polyethylene-laminated polypropylene films printed with ink incorporating microencapsulated cinnamon oil using a large-scale film production system effectively repelled Indian meal moth larvae. Without altering the tensile and moisture barrier properties of the film, microencapsulation resulted in the release of an active repellent for extended periods with a high thermal stability of cinnamon oil, enabling commercial film production at high temperatures. This anti-insect film system may have applications to other food-packaging films that use the same ink-printing platform. © 2018 Institute of Food Technologists®.

Novel microstructure in spin coated polyaniline thin films

Energy Technology Data Exchange (ETDEWEB)

Verma, Deepak; Dutta, V [Photovoltaic Laboratory, Centre for Energy Studies, Indian Institute of Technology Delhi, Hauz Khas, New Delhi-110016 (India)

2007-05-08

Polyaniline (Pani) thin films doped with camphor sulfonic acid (CSA) have been deposited on glass substrates using the spin coating technique. Pani is chemically synthesized by an oxidation method at {approx}0 deg. C. Pani-CSA films show a hexagonal structure in scanning electron micrographs, which occurs due to the crystalline growth of CSA. A dense hexagonal structure is visible for film deposited at 800 rpm, but it becomes sparser as the revolutions per minute are increased (1200, 1500 and 2000 rpm). Electronic transition of quinoid units cause an absorption shoulder at {approx}900 nm for films deposited at 1200, 1500 and 2000 rpm, which is not observed for film deposited at 800 rpm.

Deformation limits of polymer coated metal sheets

NARCIS (Netherlands)

Van Den Bosch, M.J.W.J.P.; Schreurs, P.J.G; Geers, M.G.D.

2005-01-01

Polymer coated metals are increasingly used by the packaging and automotive industry. During industrial deformation processes (drawing, roll-forming, bending etc.) the polymer-metal laminate is highly deformed at high deformation rates. These forming conditions can affect the mechanical integrity

Gold coated metal nanostructures grown by glancing angle deposition and pulsed electroplating

Science.gov (United States)

Grüner, Christoph; Reeck, Pascal; Jacobs, Paul-Philipp; Liedtke, Susann; Lotnyk, Andriy; Rauschenbach, Bernd

2018-05-01

Nickel based nanostructures are grown by glancing angle deposition (GLAD) on flat and pre-patterned substrates. These fabricated porous thin films were subsequently coated by pulsed electroplating with gold. The morphology and conformity of the gold coating were investigated by scanning electron microscopy and X-ray diffraction. Controlled growth of closed gold layers on the nanostructures could be achieved, while the open-pore structure of the nanosculptured thin films was preserved. Such gold coated nanostructures are a candidate for optical sensing and catalysis applications. The demonstrated method can be applied for numerous material combinations, allowing to provide GLAD thin films with new surface properties.

Drying of latex films and coatings: Reconsidering the fundamental mechanisms

DEFF Research Database (Denmark)

Kiil, Søren

2006-01-01

The two existing theories describing drying of latex films or coatings are reconsidered. Subsequently, a novel mathematical drying model is presented, the simulations of which can match and explain experimental drying rate data of two previous investigations with latex films. In contrast to previ......The two existing theories describing drying of latex films or coatings are reconsidered. Subsequently, a novel mathematical drying model is presented, the simulations of which can match and explain experimental drying rate data of two previous investigations with latex films. In contrast...... to previous model studies, but in agreement with observations, simulations suggest that during the falling rate period of the drying process of a latex film, a porous skin of partly coalesced latex particles is indeed formed, which limits transport of water vapour from the receding air-liquid interphase...... to the surface of the film. The value of the effective diffusion coefficient of water vapour in the dry and partly coalesced layer (7 x 10(-7) m(2)/s at 19-24 degrees C), the adjustable parameter of the model for the falling rate period, was found to be independent of initial wet film thickness (89-1322 mu m...

Nanostructured films of metal particles obtained by laser ablation

Energy Technology Data Exchange (ETDEWEB)

Muniz-Miranda, M., E-mail: muniz@unifi.it [Dipartimento di Chimica “U. Schiff”, Università di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino (Italy); Gellini, C. [Dipartimento di Chimica “U. Schiff”, Università di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino (Italy); Giorgetti, E.; Margheri, G.; Marsili, P. [Istituto Sistemi Complessi (CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Lascialfari, L.; Becucci, L. [Dipartimento di Chimica “U. Schiff”, Università di Firenze, Via della Lastruccia 3, 50019 Sesto Fiorentino (Italy); Trigari, S. [Istituto Sistemi Complessi (CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Giammanco, F. [Dipartimento di Fisica “E. Fermi”, Università di Pisa, Largo Pontecorvo 3, 56127 Pisa (Italy)

2013-09-30

Colloidal dispersions of silver and gold nanoparticles were obtained in pure water by ablation with nanosecond pulsed laser. Then, by filtration of the metal particles on alumina, we fabricated nanostructured films, whose surface morphology was examined by atomic force microscopy (AFM) and related to surface-enhanced Raman scattering (SERS) after adsorption of adenine. - Highlights: • Ag and Au colloidal nanoparticles were obtained by laser ablation. • Nanostructured Ag and Au films were fabricated by filtration of metal nanoparticles. • Surface morphology of metal films was investigated by atomic force microscopy. • Surface-enhanced Raman spectra (SERS) of adenine on metal films were obtained. • SERS enhancements were related to the surface roughness of the metal films.

Characterization of CuS nanocrystalline thin films synthesized by chemical bath deposition and dip coating techniques

International Nuclear Information System (INIS)

Chaki, Sunil H.; Deshpande, M.P.; Tailor, Jiten P.

2014-01-01

CuS thin films were synthesized by chemical bath deposition and dip coating techniques at ambient temperature. The energy dispersive analysis of X-rays of the thin films confirmed that both the as synthesized thin films are stoichiometric. The X-ray diffraction of the chemical bath deposited and dip coating deposited thin films showed that the films possess hexagonal structure having lattice parameters, a = b = 3.79 A and c = 16.34 A. The crystallite sizes determined from the X-ray diffraction data using Scherrer's formula for the chemical bath deposition and dip coating deposition thin films came out to be nearly 11 nm and 13 nm, respectively. The optical microscopy of the as deposited thin films surfaces showed that the substrates are well covered in both the deposited films. The scanning electron microscopy of the thin films clearly showed that in chemical bath deposited thin films the grain size varies from few μm to nm, while in dip coating deposited films the grain size ranges in nm. The optical bandgap determined from the optical absorbance spectrum analysis showed, chemical bath deposited thin films possess direct bandgap of 2.2 eV and indirect bandgap of 1.8 eV. In the case of dip coating deposited thin films, the direct bandgap is 2.5 eV and indirect bandgap is 1.9 eV. The d.c. electrical resistivity variation with temperature for both the deposited films showed that the resistivity decreases with temperature thus confirming the semiconducting nature. The thermoelectric power variations with temperature and the room temperature Hall Effect study of both the synthesized CuS thin films showed them to be of p-type conductivity. The obtained results are discussed in details. - Highlights: • CuS thin films were synthesized by chemical bath deposition and dip coating techniques. • The films possessed hexagonal structure. • The optical absorption showed that the films had direct and indirect bandgap. • Study of electrical transport properties

Hierarchical opal grating films prepared by slide coating of colloidal dispersions in binary liquid media.

Science.gov (United States)

Lee, Wonmok; Kim, Seulgi; Kim, Seulki; Kim, Jin-Ho; Lee, Hyunjung

2015-02-15

There are active researches on well ordered opal films due to their possible applications to various photonic devices. A recently developed slide coating method is capable of rapid fabrication of large area opal films from aqueous colloidal dispersion. In the current study, the slide coating of polystyrene colloidal dispersions in water/i-propanol (IPA) binary media is investigated. Under high IPA content in a dispersing medium, resulting opal film showed a deterioration of long range order, as well as a decreased film thickness due to dilution effect. From the binary liquid, the dried opal films exhibited the unprecedented topological groove patterns with varying periodic distances as a function of alcohol contents in the media. The groove patterns were consisted of the hierarchical structures of the terraced opal layers with periodic thickness variations. The origin of the groove patterns was attributed to a shear-induced periodic instability of colloidal concentration within a thin channel during the coating process which was directly converted to a groove patterns in a resulting opal film due to rapid evaporation of liquid. The groove periods of opal films were in the range of 50-500 μm, and the thickness differences between peak and valley of the groove were significantly large enough to be optically distinguishable, such that the coated films can be utilized as the optical grating film to disperse infra-red light. Utilizing a lowered hydrophilicity of water/IPA dispersant, an opal film could be successfully coated on a flexible Mylar film without significant dewetting problem. Copyright © 2014 Elsevier Inc. All rights reserved.

Thin film coatings for space electrical power system applications

Science.gov (United States)

Gulino, Daniel A.

1988-01-01

This paper examines some of the ways in which thin film coatings can play a role in aerospace applications. Space systems discussed include photovoltaic and solar dynamic electric power generation systems, including applications in environmental protection, thermal energy storage, and radiator emittance enhancement. Potential applications of diamondlike films to both atmospheric and space based systems are examined. Also, potential uses of thin films of the recently discovered high-temperature superconductive materials are discussed.

FEM Modeling of In-Plane Stress Distribution in Thick Brittle Coatings/Films on Ductile Substrates Subjected to Tensile Stress to Determine Interfacial Strength

Directory of Open Access Journals (Sweden)

Kaishi Wang

2018-03-01

Full Text Available The ceramic-metal interface is present in various material structures and devices that are vulnerable to failures, like cracking, which are typically due to their incompatible properties, e.g., thermal expansion mismatch. In failure of these multilayer systems, interfacial shear strength is a good measure of the robustness of interfaces, especially for planar films. There is a widely-used shear lag model and method by Agrawal and Raj to analyse and measure the interfacial shear strength of thin brittle film on ductile substrates. The use of this classical model for a type of polymer derived ceramic coatings (thickness ~18 μm on steel substrate leads to high values of interfacial shear strength. Here, we present finite element simulations for such a coating system when it is subjected to in-plane tension. Results show that the in-plane stresses in the coating are non-uniform, i.e., varying across the thickness of the film. Therefore, they do not meet one of the basic assumptions of the classical model: uniform in-plane stress. Furthermore, effects of three significant parameters, film thickness, crack spacing, and Young’s modulus, on the in-plane stress distribution have also been investigated. ‘Thickness-averaged In-plane Stress’ (TIS, a new failure criterion, is proposed for estimating the interfacial shear strength, which leads to a more realistic estimation of the tensile strength and interfacial shear strength of thick brittle films/coatings on ductile substrates.

FEM Modeling of In-Plane Stress Distribution in Thick Brittle Coatings/Films on Ductile Substrates Subjected to Tensile Stress to Determine Interfacial Strength.

Science.gov (United States)

Wang, Kaishi; Zhang, Fangzhou; Bordia, Rajendra K

2018-03-27

The ceramic-metal interface is present in various material structures and devices that are vulnerable to failures, like cracking, which are typically due to their incompatible properties, e.g., thermal expansion mismatch. In failure of these multilayer systems, interfacial shear strength is a good measure of the robustness of interfaces, especially for planar films. There is a widely-used shear lag model and method by Agrawal and Raj to analyse and measure the interfacial shear strength of thin brittle film on ductile substrates. The use of this classical model for a type of polymer derived ceramic coatings (thickness ~18 μm) on steel substrate leads to high values of interfacial shear strength. Here, we present finite element simulations for such a coating system when it is subjected to in-plane tension. Results show that the in-plane stresses in the coating are non-uniform, i.e., varying across the thickness of the film. Therefore, they do not meet one of the basic assumptions of the classical model: uniform in-plane stress. Furthermore, effects of three significant parameters, film thickness, crack spacing, and Young's modulus, on the in-plane stress distribution have also been investigated. 'Thickness-averaged In-plane Stress' (TIS), a new failure criterion, is proposed for estimating the interfacial shear strength, which leads to a more realistic estimation of the tensile strength and interfacial shear strength of thick brittle films/coatings on ductile substrates.

Development of technique for AR coating and nickel and copper metallization of solar cells. FPS Project: Product development

Science.gov (United States)

Taylor, W.

1982-01-01

Printed nickel overplated with copper and applied on top of a predeposited silicon nitride antireflective coating system for metallizing solar cells was analyzed. The ESL D and E paste formulations, and the new formulations F, G, H, and D-1 were evaluated. The nickel thick films were tested after firing for stability in the cleaning and plating solutions used in the Vanguard-Pacific brush plating process. It was found that the films are very sensitive to the leaning and alkaline copper solutions. Less sensitivity was displayed to the neutral copper solution. Microscopic and SEM observations show segregation of frit at the silicon nitride thick film interface with loose frit residues after lifting off plated grid lines.

Development of a suppression method for deposition of radioactive cobalt after chemical decontamination: Confirmation of the Suppression Mechanism with Preoxidized Ferrite Film for Deposition of Radioactive Cobalt

International Nuclear Information System (INIS)

Ito, Tsuyoshi; Hosokawa, Hideyuki; Nagase, Makoto; Aizawa, Motohiro; Fuse, Motomasa

2012-09-01

Recently, chemical decontamination at the beginning of a periodical inspection is applied to many Japanese boiling water reactor (BWR) plants in order to reduce radiation exposure. In the chemical decontamination, the oxides that have incorporated 60 Co are dissolved using reductive and oxidative chemical reagents. Some of the piping stainless steel (SS) base metal is exposed to the reactor water after this decontamination. The oxide film growth rate of the piping during plant operation just after the decontamination is higher than that just before it. Therefore, there is a possibility that the deposition amount of 60 Co on the piping just after decontamination is higher than that just before the chemical decontamination. The Hi-F Coat (Hitachi ferrite coating) process has been developed to lower recontamination after the chemical decontamination. In this process, a fine Fe 3 O 4 coating film is formed on the piping SS base metal in aqueous solution at 363 K using three chemical reagents: ferrous ion, oxidant, and pH adjuster. The growth rate of the corrosion oxide film that incorporated 60 Co on the piping during plant operation is suppressed by the fine ferrite film that blocks both diffusion of oxidant in the reactor water to the SS base metal and metal ions in the oxide film to the reactor water. As a result, the amount of 60 Co deposition is suppressed by the Hi-F coating film. In a previous report, we found that the Hi-F Coat process lowered the amount of 60 Co to 1/3 that for non-coated specimens. To improve the suppression of 60 Co deposition further, we combined the Hi-F Coat process with a pre-oxidation step which we named the pre-oxidized Hi-F Coat process. In laboratory experiments, using the pre-oxidized Hi-F Coat process we found the deposited amount of 60 Co was 1/10 that for non-coated specimens. By combining the Hi-F Coat process with the pre-oxidation step, the suppression effect of 60 Co deposition was three times higher than that of the Hi

Fabrication of indium tin oxide (ITO) thin film with pre-treated sol coating

International Nuclear Information System (INIS)

Hong, Sung-Jei; Han, Jeong-In

2004-01-01

A new pre-treated sol-coating method to fabricate an indium tin oxide (ITO) thin film is introduced in this paper. The pre-treatment sol-coating method is to form a seed layer on the substrate before spin coating of ITO sol. The pre-treatment was carried out at room temperature in order not to damage the substrate during the pre-treatment. It is effective to enhance the formation of the ITO sol film on the substrate, owing to the seed layer. The seed layer consists of ultrafine grains, which are observed at the pre-treated substrate. For the optimal pre-treatment condition, we used pre-treatment times of 24, 48, 72, and 96 hours to observe the effect on the characteristics of ITO sol film. As a result, the lowest resistance could be achieved with a pre-treatment time of 72 hours. The optical transmittance of the ITO sol film with the pre-treatment time of 72 hours exceeded 80 % at a wavelength of 400 nm. So, an ITO sol film with good electrical and optical properties could be fabricated by using the pretreatment sol coating.

Polymer-Silica nanoparticles composite films as protective coatings for stone-based monuments

Energy Technology Data Exchange (ETDEWEB)

Manoudis, P [Department of Chemical Engineering, Aristotle University of Thessaloniki, 54124, Thessaloniki (Greece); Papadopoulou, S [Department of Chemical Engineering, Aristotle University of Thessaloniki, 54124, Thessaloniki (Greece); Karapanagiotis, I [' Ormylia' Art Diagnosis Centre, Ormylia, Chalkidiki, 63071 (Greece); Tsakalof, A [Medical Department, University of Thessaly, Larissa, 41222 (Greece); Zuburtikudis, I [Department of Industrial Design Engineering, TEI of Western Macedonia, Kozani, 50100 (Greece); Panayiotou, C [Department of Chemical Engineering, Aristotle University of Thessaloniki, 54124, Thessaloniki (Greece)

2007-04-15

The decrease of surface energy of mineral substrates similar to those used in many stone monuments of cultural heritage by the application of protective polymer coatings along with the simultaneous increase of their surface roughness can increase their ability to repel water substantially. In this work, the effect of artificially induced roughness on the water repellency of mineral substrates coated with protective polymer films was investigated. Natural marble samples or home made calcium carbonate blocks were tried as the mineral substrates. The roughness increase was achieved by mineral chemical etching or by creation of nanoscale binary composition film on the substrate surface. PMMA and PFPE were the polymers used, while different-sized silica nanoparticles were employed for the production of the nanocomposite films. Examination of the coated and uncoated surfaces with profilometry and AFM and measurements of water contact angles reveal a pronounced effect of the surface roughness on water repellency. Especially in the case of nanocomposite coatings, the surfaces become super-hydrophobic. This result indicates that the nanoscale binary composition film scheme, which is characterized by its simplicity and low cost, is a suitable candidate for the water protection of stone-based monuments on large scale.

Polymer-Silica nanoparticles composite films as protective coatings for stone-based monuments

International Nuclear Information System (INIS)

Manoudis, P; Papadopoulou, S; Karapanagiotis, I; Tsakalof, A; Zuburtikudis, I; Panayiotou, C

2007-01-01

The decrease of surface energy of mineral substrates similar to those used in many stone monuments of cultural heritage by the application of protective polymer coatings along with the simultaneous increase of their surface roughness can increase their ability to repel water substantially. In this work, the effect of artificially induced roughness on the water repellency of mineral substrates coated with protective polymer films was investigated. Natural marble samples or home made calcium carbonate blocks were tried as the mineral substrates. The roughness increase was achieved by mineral chemical etching or by creation of nanoscale binary composition film on the substrate surface. PMMA and PFPE were the polymers used, while different-sized silica nanoparticles were employed for the production of the nanocomposite films. Examination of the coated and uncoated surfaces with profilometry and AFM and measurements of water contact angles reveal a pronounced effect of the surface roughness on water repellency. Especially in the case of nanocomposite coatings, the surfaces become super-hydrophobic. This result indicates that the nanoscale binary composition film scheme, which is characterized by its simplicity and low cost, is a suitable candidate for the water protection of stone-based monuments on large scale

Study the polymer coating for detecting and surface decontamination of uranium

International Nuclear Information System (INIS)

Pham Thi Quynh Luong; Nguyen Van Chinh

2011-01-01

Strippable polymer coating is one of the methods for effective surface decontamination. It has been developed in both detecting and removing the radioactive isotope and heavy metal elements from contaminated surfaces. A polymer coating is produced to be sprayed or brushed on contaminated material of uranium. The places of U contamination is shown by color change of polymer coating. As the polymer coating is dried up to form a strong film, the contaminations are absorbed in to the coating and contaminated surfaces are cleaned by removing the film. (author)

Improved Metallography Of Thermal-Barrier Coatings

Science.gov (United States)

Brindley, William J.; Leonhardt, Todd A.

1991-01-01

New technique for preparation of metallographic samples makes interpretation of images of pores and microcracks more reliable. Involves use of vacuum epoxy infiltration and interference-film coating to reduce uncertainty. Developed for inspection of plasma-sprayed ceramic thermal-barrier coatings on metals but applicable to other porous, translucent materials, including many important ceramics.

Electron grafted barrier coatings for packaging film modification

International Nuclear Information System (INIS)

Rangwalla, I.J.; Nablo, S.V.

1993-01-01

The O 2 barrier performance of organosilane films, coated, dried and electron beam grafted to polyolefin film has been studied. Excellent anti-scalping properties based upon limonene (dipentene) transmission measurements have also been observed. Results are also reported on O 2 permeability reduction when the process is applied to common barrier polymers such as EVOH and acrylonitrile. Experience with its in-line application on LDPE is discussed. (author)

Thin Glass Coatings for the Corrosion Protection of Metals

DEFF Research Database (Denmark)

Lampert, Felix

in corrosion sensitive applications. Since the deposition of SiOx thin films is a well-established technology, the SOG technology was directly benchmarked to PVD-based SiO2 coatings. The coating adhesion was assessed by cross cut testing and increasing load scratch testing and the efficiency of the sub...... with localized corrosion and do not impact the heat transfer or the component performance. The herein presented approach focuses primarily on the formation of SiOx-like thin films from Hydrogen Silsesquioxane (HSQ) –based “spin-on-glass” (SOG) precursor. The technology is well known for the deposition...

Surface analysis of thin film coatings on container glass

Energy Technology Data Exchange (ETDEWEB)

Bhargava, A. [GCC Pty Ltd., Jindalee, QLD (Australia); Wood, B. [The University of Queensland, Brisbane, QLD (Australia). Department of Chemistry

1999-12-01

Full text: Container glass is generally coated with a tin oxide layer followed by a coating of polymer. These coatings are believed to improve the mechanical properties of container glass as well as aid in the application of advertising labels to glass. The tin oxide layer on commercial beer bottles has a total thickness of about 15-20nm which consists of an interfacial layer comprising 70-85% of the total thickness. The polymer coating is about 2-5nm thick and also possesses an interfacial layer with tin oxide. A PHI Model 560 XPS/ SAM/ SIMS multi-technique system Is used to estimate concentration profiles of Sn, O, C, Si, Ca, Na and O. A combination of XPS, AES and SIMS is necessary to describe the coatings. Instrumental conditions and sample preparation methods are developed to optimize the analysis of thin films on glass. The coating comprises of three areas, namely (A) where polymer and tin co-exist (B) a pure tin oxide layer and (C) where tin co-exists with glass. By varying the chemical source of tin, it is possible to systematically vary the thickness of the interface and the concentration profile of Sn. Using XRD, crystalline phase(s) could be detected in tin oxide films as thin as 15nm. While the principle phase is cassiterite, a second phase is also detected which is believed to originate from the interface. Using a UMIS 2000 nanoindentor system, instrumental parameters are optimized for measurement of elastic modulus of films at varying depths, i.e. from surface of coating to the bulk of the glass. A sharp rise is observed at depth corresponding to the interface which is indicative of the significance of the interfacial layer. Samples are prepared by systematic ion-milling which are representative of various regions of the coating, namely (A), (B) and (C). These samples are analyzed by XRD and TEM. Based on these studies, a structural model of tin oxide layer and interface is presented to explain increase in elastic modulus at the interface. Copyright

Surface analysis of thin film coatings on container glass

International Nuclear Information System (INIS)

Bhargava, A.; Wood, B.

1999-01-01

Full text: Container glass is generally coated with a tin oxide layer followed by a coating of polymer. These coatings are believed to improve the mechanical properties of container glass as well as aid in the application of advertising labels to glass. The tin oxide layer on commercial beer bottles has a total thickness of about 15-20nm which consists of an interfacial layer comprising 70-85% of the total thickness. The polymer coating is about 2-5nm thick and also possesses an interfacial layer with tin oxide. A PHI Model 560 XPS/ SAM/ SIMS multi-technique system Is used to estimate concentration profiles of Sn, O, C, Si, Ca, Na and O. A combination of XPS, AES and SIMS is necessary to describe the coatings. Instrumental conditions and sample preparation methods are developed to optimize the analysis of thin films on glass. The coating comprises of three areas, namely (A) where polymer and tin co-exist (B) a pure tin oxide layer and (C) where tin co-exists with glass. By varying the chemical source of tin, it is possible to systematically vary the thickness of the interface and the concentration profile of Sn. Using XRD, crystalline phase(s) could be detected in tin oxide films as thin as 15nm. While the principle phase is cassiterite, a second phase is also detected which is believed to originate from the interface. Using a UMIS 2000 nanoindentor system, instrumental parameters are optimized for measurement of elastic modulus of films at varying depths, i.e. from surface of coating to the bulk of the glass. A sharp rise is observed at depth corresponding to the interface which is indicative of the significance of the interfacial layer. Samples are prepared by systematic ion-milling which are representative of various regions of the coating, namely (A), (B) and (C). These samples are analyzed by XRD and TEM. Based on these studies, a structural model of tin oxide layer and interface is presented to explain increase in elastic modulus at the interface. Copyright

Potential assisted fabrication of metal-ceramic composite coatings

International Nuclear Information System (INIS)

Knote, A.; Schindler, U.; Krueger, H.G.; Kern, H.

2003-01-01

A possibility to produce uniform metal-ceramic composite coatings with a high content of ceramic particles up to 60 vol.% will be presented in this study. This method includes a combination of electrophoretic deposition and electrolytic deposition by several steps. A yttria-stabilized zirconia coating (Tosoh TZ-8Y) was first electrophoretically deposited on a ferritic steel plate and then sintered by 1100 C to an open porous layer. In the next step nickel was electrodeposited into the pores of the layer. By a final annealing step it was possible to improve the bonding of the composit coating on the substrate by diffusion of the metal components. (Abstract Copyright [2003], Wiley Periodicals, Inc.) [de

Growth of CdS thin films on indium coated glass substrates via chemical bath deposition and subsequent air annealing

Energy Technology Data Exchange (ETDEWEB)

Ghosh, Biswajit; Kumar, Kamlesh; Singh, Balwant Kr; Banerjee, Pushan; Das, Subrata, E-mail: neillohit@yahoo.co.in

2014-11-30

Graphical abstract: - Highlights: • CdS film grown on indium coated glass substrates via CBD and subsequent annealing. • Disappearance of the indium (1 1 2) peak confirms interdiffusion at 300 °C. • SIMS indicates the subsequent interdiffusion at progressively higher temperature. • Composite In–CdS layer showed lower photosensitivity compared to pure CdS. - Abstract: In the present work attempts were made to synthesize indium doped CdS films by fabricating In/CdS bilayers using CBD-CdS on vacuum evaporated In thin films and subsequent air annealing. 135 nm CdS films were grown onto 20 nm and 35 nm indium coated glass substrate employing chemical bath deposition technique. The In/CdS bilayers thus formed were subjected to heat treatment at the temperatures between 200 and 400 °C for 4 min in the muffle furnace to facilitate indium to diffuse into the CdS films. XRD pattern ascertained no noticeable shift in lattice constant implying grain boundary metal segregation, while secondary ion mass spectrometry indicated the diffusion profile of indium into CdS matrices. Mass spectrometry results showed that substantial diffusion of indium had been taken place within CdS at 400 °C. Dark and photocurrent with different illumination time were measured to ascertain the photosensitivity of pure and composite CdS films.

Microstructural, thermal and mechanical behavior of co-sputtered binary Zr–Cu thin film metallic glasses

Energy Technology Data Exchange (ETDEWEB)

Apreutesei, M. [MATEIS Laboratory-INSA de Lyon, Bât. B. Pascal, 7 Avenue Jean Capelle, 69621 Villeurbanne Cedex (France); Steyer, P., E-mail: philippe.steyer@insa-lyon.fr [MATEIS Laboratory-INSA de Lyon, Bât. B. Pascal, 7 Avenue Jean Capelle, 69621 Villeurbanne Cedex (France); Joly-Pottuz, L. [MATEIS Laboratory-INSA de Lyon, Bât. B. Pascal, 7 Avenue Jean Capelle, 69621 Villeurbanne Cedex (France); Billard, A. [LERMPS-UTBM, Site de Montbéliard, 90010 Belfort Cédex (France); Qiao, J.; Cardinal, S. [MATEIS Laboratory-INSA de Lyon, Bât. B. Pascal, 7 Avenue Jean Capelle, 69621 Villeurbanne Cedex (France); Sanchette, F. [LASMIS-UTT, UMR CNRS 6279, 12 rue Marie Curie, CS 42060, 10004 Troyes Cedex (France); Pelletier, J.M.; Esnouf, C. [MATEIS Laboratory-INSA de Lyon, Bât. B. Pascal, 7 Avenue Jean Capelle, 69621 Villeurbanne Cedex (France)

2014-06-30

Bulk metallic glasses have attracted considerable attention over the last decades for their outstanding mechanical features (high strength, super-elasticity) and physico-chemical properties (corrosion resistance). Recently, some attempts to assign such original behavior from bulk materials to modified surfaces have been reported in the literature based on multicomponent alloys. In this paper we focused on the opportunity to form a metallic glass coating from the binary Zr–Cu system using a magnetron co-sputtering physical vapor deposition process. The composition of the films can be easily controlled by the relative intensities applied to both pure targets, which made possible the study of the whole Zr–Cu system (from 13.4 to 85.0 at.% Cu). The chemical composition of the films was obtained by energy dispersive X-ray spectroscopy, and their microstructure was characterized by scanning and transmission electron microscopy. The thermal stability of the films was deduced from an in situ X-ray diffraction analysis (from room temperature up to 600 °C) and correlated with the results of the differential scanning calorimetry technique. Their mechanical properties were determined by nanoindentation experiments. - Highlights: • We reported deposition of Zr-Cu thin film metallic glasses by co-sputtering • Films were XRD-amorphous in a wide composition range (33.3 – 85.0 at.% Cu) • Microstructure investigation revealed some local nanodomains • We examined the thermal stability by means of in situ X-ray diffraction • Nanoindentation was used to obtained mechanical properties of thin films.

Simulation and parametric study of a film-coated controlled-release pharmaceutical.

Science.gov (United States)

Borgquist, Per; Zackrisson, Gunnar; Nilsson, Bernt; Axelsson, Anders

2002-04-23

Pharmaceutical formulations can be designed as Multiple Unit Systems, such as Roxiam CR, studied in this work. The dose is administrated as a capsule, which contains about 100 individual pellets, which in turn contain the active drug remoxipride. Experimental data for a large number of single pellets can be obtained by studying the release using microtitre plates. This makes it possible to study the release of the individual subunits making up the total dose. A mathematical model for simulating the release of remoxipride from single film-coated pellets is presented including internal and external mass transfer hindrance apart from the most important film resistance. The model can successfully simulate the release of remoxipride from single film-coated pellets if the lag phase of the experimental data is ignored. This was shown to have a minor influence on the release rate. The use of the present model is demonstrated by a parametric study showing that the release process is film-controlled, i.e. is limited by the mass transport through the polymer coating. The model was used to fit the film thickness and the drug loading to the experimental release data. The variation in the fitted values was similar to that obtained in the experiments.

Application of fluoridated hydroxyapatite thin film coatings using KrF pulsed laser deposition.

Science.gov (United States)

Hashimoto, Yoshiya; Ueda, Mamoru; Kohiga, Yu; Imura, Kazuki; Hontsu, Shigeki

2018-06-08

Fluoridated hydroxyapatite (FHA) was investigated for application as an implant coating for titanium bone substitute materials in dental implants. A KrF pulsed excimer deposition technique was used for film preparation on a titanium plate. The compacts were ablated by laser irradiation at an energy density of 1 J/cm 2 on an area 1×1 mm 2 with the substrate at room temparature. Energydispersive spectrometric analysis of the FHA film revealed peaks of fluorine in addition to calcium and phosphorus. X-ray diffraction revealed the presence of crystalline FHA on the FHA film after a 10 h post annealing treatment at 450°C. The FHA film coating exhibited significant dissolution resistance to sodium phosphate buffer for up to 21 days, and favorable cell attachment of human mesenchymal stem cells compared with HA film. The results of this study suggest that FHA coatings are suitable for real-world implantation applications.

Adhesion and corrosion studies of a lithium based conversion coating film on the 2024 aluminum alloy

International Nuclear Information System (INIS)

Castro, M.R.S.; Nogueira, J.C.; Thim, G.P.; Oliveira, M.A.S.

2004-01-01

AA2024-T3-aluminum alloy surfaces were coated using non-chromate and chromate conversion coatings. All coatings were painted with the 10P4-2-primer epoxy resin. Independent on the film formation process, films passed on the substrate/conversion coating wet tape adhesion test. However, only the chromate conversion coating passed on the conversion coating/primer epoxy resin adhesion test. Electrochemical corrosion measurements showed that non-chromate conversion coated surfaces present lower corrosion current density, bigger polarization resistance and less negative corrosion potential than chromate conversion coated surfaces

Influence of additives on melt viscosity, surface tension, and film formation of dry powder coatings.

Science.gov (United States)

Sauer, Dorothea; McGinity, James W

2009-06-01

Limited information on thermally cured dry-powder coatings used for solid dosage forms has been available in the literature. The aim of this study was to characterize the film formation process of Eudragit L 100-55 dry-powder coatings and to investigate the influence of film additives on melt viscosity and surface tension. The coating process employed no liquids and the plasticizer was combined with the polymer using hot melt extrusion. Thermoanalytical methods including differential scanning calorimetry and thermogravimetric analysis (TGA) were used to investigate the thermal properties of the dry-coating formulations. The rheological behavior of the coating formulations were characterized with the extrusion torque, and the surface energy parameters were determined from contact angle measurements. The influence of the level of triethyl citrate (TEC) as plasticizer and polyethylene glycol (PEG) 3350 in the polymer film on film formation was investigated using a digital force tester. TGA confirmed thermal stability of all coating excipients at the investigated curing conditions. Increasing TEC levels and the addition of PEG 3350 as a low melting excipient in the coating reduced the viscosity of the polymer. Plasticization of the polymer with TEC increased the surface free energy, whereas the admixture of 10% PEG 3350 did not affect the surface free energy of Eudragit L 100-55. The spreading coefficient of the polymers over two sample tablet formulations was reduced with increasing surface free energy. During the curing process, puncture strength, and elongation of powder-cast films increased. The effect of curing time on the mechanical properties was dependent on the plasticizer content. The incorporation of TEC and PEG 3350 into the Eudragit L 100-55 powder coating formulation improved film formation. Mechanical testing of powder-cast films showed an increase of both elongation and puncture strength over the curing process as criterion for polymer particle fusion

High Precision Metal Thin Film Liftoff Technique

Science.gov (United States)

Brown, Ari D. (Inventor); Patel, Amil A. (Inventor)

2015-01-01

A metal film liftoff process includes applying a polymer layer onto a silicon substrate, applying a germanium layer over the polymer layer to create a bilayer lift off mask, applying a patterned photoresist layer over the germanium layer, removing an exposed portion of the germanium layer, removing the photoresist layer and a portion of the polymer layer to expose a portion of the substrate and create an overhanging structure of the germanium layer, depositing a metal film over the exposed portion of the substrate and the germanium layer, and removing the polymer and germanium layers along with the overlaying metal film.

Production of metal and metal-ceramic coatings on D-Gun Ob

International Nuclear Information System (INIS)

Gavrilenko, T.P.; Nikolaev, Y.A.; Ulianitsky, V.Y.

1995-01-01

Optimization of the detonation spraying process has been made for the production of metal and metal-ceramics coatings with the D-Gun Ob. Owing to the ability of Ob to work with several fuels and an inert diluent simultaneously, variation of detonation regimes in a wide range is possible, and because of localized powder injection in the D-Gun barrel, high uniformity of parameters of powder particles is achieved. The best conditions for particle heating and acceleration were calculated with the help of mathematical simulation, and the corresponding regimes were realized on D-Gun Ob. High-quality aluminum, copper, nickel, and nickel-chromium-silicon-carbon-boron alloy coatings were produced by using only propane fuel. Chromium carbide with nickel and tungsten carbide with cobalt coatings were produced with addition of acetylene. Optimal efficiency and high bonding strength were achieved for all powders. Data on microhardness, bonding strength, and efficiency are presented

Rapid synthesis of flexible conductive polymer nanocomposite films

International Nuclear Information System (INIS)

Blattmann, C O; Sotiriou, G A; Pratsinis, S E

2015-01-01

Polymer nanocomposite films with nanoparticle-specific properties are sought out in novel functional materials and miniaturized devices for electronic and biomedical applications. Sensors, capacitors, actuators, displays, circuit boards, solar cells, electromagnetic shields and medical electrodes rely on flexible, electrically conductive layers or films. Scalable synthesis of such nanocomposite films, however, remains a challenge. Here, flame aerosol deposition of metallic nanosliver onto bare or polymer-coated glass substrates followed by polymer spin-coating on them leads to rapid synthesis of flexible, free-standing, electrically conductive nanocomposite films. Their electrical conductivity is determined during their preparation and depends on substrate composition and nanosilver deposition duration. Accordingly, thin (<500 nm) and flexible nanocomposite films are made having conductivity equivalent to metals (e.g. 5  × 10 4 S cm −1 ), even during repetitive bending. (paper)

Analysis Of Corrosion Resistant Film On AI-Mg-Si Coated By Rare Earth Metal

International Nuclear Information System (INIS)

Darajati, Rusdiana; Ihsan, Mohammad; Wuryanto

2001-01-01

Corrosion analysis of AI-Mg-Si alloy which given corrosion-resistant film of a rare earth oxide coating incorporated with a uniform aluminum oxide film which has been formed on the aluminum alloy surface has been done. The measurement techniques were E corr versus time, polarization resistance, potentiodynamic and SEM (Scanning Electron Microscope for surface analysis. Potential corrosion in water environment tend to bigger with more time for four samples except sample AIMgSi that dipped into triethanolamine. ln HCl pH=1 potential corrosion sample AIMgSi, AIMgSi that dipped into triethanolamine, AIMgSi that dipped into triethanolamine and Ce Cl) tend to bigger with more time while sample AIMgSi that dipped into triethanolamine and YCI 3 or RECI 3 tend to smaller with more time. Potential corrosion in NaOH pH= 13 tend to bigger with more time for all samples. Corrosion rate for sample AIMgSi that dipped into triethanolamine in water environment relatively slower (0,0205 mpy), while in HCl pH=1 and NaOH pH=13 corrosion rate sample AIMgSi that dipped into triethanolamine and YCI 3 relatively slower, respectively are 0,1157 mpy and 2468,26 mpy. Sample AIMgSi that dipped into triethanolamine and RECI 3 in water environment has passivation and trans passivation area while four simple don't have passivation area, in H CI pH=1 all samples generally have passivation area at the same current density range while in NaOH pH= 13 sample AIMgSi has trans passivation area at a potential of about 800 mV while four other sample have passivation area at a potential of about-850-1500 mV. SEM analysis show that the coating layer which formed on the sample surface less protective especially in HCl pH= land NaOH pH=13

Sensitive resonant gas sensor operating in air with metal organic frameworks coating

KAUST Repository

Jaber, Nizar; Ilyas, Saad; Shekhah, Osama; Eddaoudi, Mohamed; Younis, Mohammad I.

2017-01-01

We report a practical resonant gas sensor that is uniformly coated with metal organic frameworks (MOFs) and excited near the higher order modes for a higher attained sensitivity. The resonator is based on an electrostatically excited clamped-clamped microbeam. The microbeam is fabricated from a polyimide layer coated from the top with Cr/Au and from the bottom with Cr/Au/Cr layer. The geometry of the resonator is optimized to reduce the effect of the squeeze film damping, thereby allowing operation under atmospheric pressure. The electrostatic force electrode is designed to enhance the excitation of the second mode of vibration with the minimum power required. Significant frequency shift (kHz) is demonstrated for the first time upon water vapor, acetone, and ethanol exposure due to the MOFs functionalization and the higher order modes excitation. Also, the adsorption dynamics and MOF selectivity is investigated by studying the decaying time constants of the response upon gas exposure.

Sensitive resonant gas sensor operating in air with metal organic frameworks coating

KAUST Repository

Jaber, Nizar

2017-08-09

We report a practical resonant gas sensor that is uniformly coated with metal organic frameworks (MOFs) and excited near the higher order modes for a higher attained sensitivity. The resonator is based on an electrostatically excited clamped-clamped microbeam. The microbeam is fabricated from a polyimide layer coated from the top with Cr/Au and from the bottom with Cr/Au/Cr layer. The geometry of the resonator is optimized to reduce the effect of the squeeze film damping, thereby allowing operation under atmospheric pressure. The electrostatic force electrode is designed to enhance the excitation of the second mode of vibration with the minimum power required. Significant frequency shift (kHz) is demonstrated for the first time upon water vapor, acetone, and ethanol exposure due to the MOFs functionalization and the higher order modes excitation. Also, the adsorption dynamics and MOF selectivity is investigated by studying the decaying time constants of the response upon gas exposure.

Spin-coating deposition of PbS and CdS thin films for solar cell application

Energy Technology Data Exchange (ETDEWEB)

Patel, Jayesh; Mighri, Frej [Laval University, CREPEC, Department of Chemical Engineering, Quebec, QC (Canada); Ajji, Abdellah [Ecole Polytechnique, CREPEC, Chemical Engineering Department, Montreal, QC (Canada); Tiwari, Devendra; Chaudhuri, Tapas K. [Charotar University of Science and Technology (CHARUSAT), Dr. K.C. Patel Research and Development Centre, Anand District, Gujarat (India)

2014-12-15

In this work, we describe a simple spin-coating deposition technique for lead sulphide (PbS) and cadmium sulphide (CdS) films from a methanolic metal-thiourea complex. The characterization of the films by X-ray diffraction and X-ray photoelectron spectroscopy techniques revealed that pure cubic phase PbS and CdS layers were formed via this method. As shown by atomic force microscopy and scanning electron microscopy results, both films were homogeneous and presented a smooth surface. Optical properties showed that the energy band gap of PbS and CdS films were around 1.65 and 2.5 eV, respectively. The PbS film is p-type in nature with an electrical conductivity of around 0.8 S/cm. The hole concentration and mobility were 2.35 x 10{sup 18} cm{sup -3} and 2.16 x 10{sup -3} cm{sup 2}/V/s, respectively, as determined from Hall measurement. Both films were used to develop a thin film solar cell device of graphite/PbS/CdS/ITO/glass. Device characterization showed the power conversion efficiency of around 0.24 %. The corresponding open circuit voltage, short circuit current and fill factor were 0.570 V, 1.32 mA/cm{sup 2} and 0.32, respectively. (orig.)

Corrosion protection of metals by phosphate coatings and ecologically beneficial alternatives. Properties and mechanisms

International Nuclear Information System (INIS)

Weng Duan.

1995-01-01

The corrosion and protection characteristics of inorganic zinc and manganese phosphate coatings in aqueous solution have been examined by physical methods, accelerated corrosion tests and electrochemical polarization and impedance measurements. Some water-soluble organic films have been evaluated for the temporary protection of metal parts as the ecologically beneficial alternatives to phosphate coatings. The results show that zinc phosphate is a better insulator than manganese phosphate, but the porosity of the former is inferior to that of the latter. In neutral and alkaline solutions the anodic current of both zinc and manganese phosphates decreases and their open potential moves in a positive direction. In acidic medium both the polarization current and the open potential are close to those of the substrate. Confirmed by the impedance measurements, the corrosion of phosphated steel in acidic solution is controlled by a dissolution reaction, in neutral medium is first reaction controlled then diffusion controlled, and in alkaline environment only diffusion controlled. The insulation of acrylate+copolymer, epoxy and inhibitor+bonding materials is superior to that of zinc or manganese phosphates. In general, most of the alternatives can afford a better temporary protection for metal parts compared to inorganic phosphate coatings. The corrosion failure of inorganic phosphate coatings is mainly induced by the electrochemical dissolution of the substrate. This electrochemical process initiates at the bottom of the pores within the coating. In neutral solution, the hydrolysis of corrosion products decrease the pH value of the solution in the anodic zone, resulting in an acidic dissolution of phosphate coatings. At the same time, the depolarization of oxygen increases the pH value in the cathodic zone, causing an alkaline hydrolysis of phosphates. (author) figs., tabs., 149 refs

Direct fabrication of rigid microstructures on a metallic roller using a dry film resist

International Nuclear Information System (INIS)

Jiang, Liang-Ting; Huang, Tzu-Chien; Chang, Chih-Yuan; Ciou, Jian-Ren; Yang, Sen-Yeu; Huang, Po-Hsun

2008-01-01

This paper presents a novel method to fabricate a metallic roller mold with microstructures on its surface using a dry film resist (DFR). The DFR is laminated uniformly onto the curvy surface of a copper roller. After that, the micro-scale photoresist on the surface of the roller can be patterned by non-planar lithography using a flexible film photomask, followed by ferric chloride wet etching to obtain the desired microstructures. This method overcomes the uniformity issue of photoresist coating on rollers, and solves the molds sliding problem during the embossing process because the microstructures are fabricated directly on the roller surface. Furthermore, the rigid metallic roller mold has excellent strength durability and temperature endurance, which can be used in roller hot embossing with a high embossing pressure. The fabricated microstructure roller mold is used as a mold in the hybrid extrusion roller embossing process and successfully fabricates uniform micro-scale prominent line arrays on PC films. This result proves that the roller fabricated by this method can be successfully used in roller embossing for microstructure mass production. The excellent flatness of dry film resist laminating is the key in this fabrication process. The flexible film photomask can be easily designed using CAD software; this roller fabrication method enhances the design flexibility and reduces the cost and time

Hard Chrome-Coated and Fullerene-Doped Metal Surfaces in Orthopedic Bearings.

Science.gov (United States)

Sonntag, Robert; Feige, Katja; Dos Santos, Claudia Beatriz; Kretzer, Jan Philippe

2017-12-20

Metal-on-metal bearings for total hip replacements have been introduced as an alternative to polyethylene in young and more active patients. These have, however, been shown to be prone to implant malpositioning and have been limited by some specific design features. In that context, coatings present an option to increase wear resistance by keeping the high fracture strength of the metal substrate. A custom-made electroplating setup was designed for the coating of CoCr substrates using (a) an industrial standard chromium electrolyte; (b) a custom-made hexavalent chromium (Cr 6+ ) electrolyte with a reduced chromium trioxide (CrO₃) content, both without solid additives and (c) with the addition of fullerene (C 60 ) nanoparticles; and (d) a trivalent chromium (Cr 3+ ) electrolyte with C 60 addition. All coatings showed an increase in microhardness compared with the metal substrate. Trivalent coatings were thinner (10 µm) than the hexavalent coatings (23-40 µm) and resulted in increased roughness and crack density. Wear was found to be reduced for the hexavalent chromium coatings by 70-84% compared with the CoCr-CoCr reference bearing while the trivalent chromium coating even increased wear by more than 300%. The addition of fullerenes to the electrolyte did not show any further tribological effect.

Hard Chrome-Coated and Fullerene-Doped Metal Surfaces in Orthopedic Bearings

Directory of Open Access Journals (Sweden)

Robert Sonntag

2017-12-01

Full Text Available Metal-on-metal bearings for total hip replacements have been introduced as an alternative to polyethylene in young and more active patients. These have, however, been shown to be prone to implant malpositioning and have been limited by some specific design features. In that context, coatings present an option to increase wear resistance by keeping the high fracture strength of the metal substrate. A custom-made electroplating setup was designed for the coating of CoCr substrates using (a an industrial standard chromium electrolyte; (b a custom-made hexavalent chromium (Cr6+ electrolyte with a reduced chromium trioxide (CrO3 content, both without solid additives and (c with the addition of fullerene (C60 nanoparticles; and (d a trivalent chromium (Cr3+ electrolyte with C60 addition. All coatings showed an increase in microhardness compared with the metal substrate. Trivalent coatings were thinner (10 µm than the hexavalent coatings (23–40 µm and resulted in increased roughness and crack density. Wear was found to be reduced for the hexavalent chromium coatings by 70–84% compared with the CoCr–CoCr reference bearing while the trivalent chromium coating even increased wear by more than 300%. The addition of fullerenes to the electrolyte did not show any further tribological effect.

Applicability of near-infrared spectroscopy in the monitoring of film coating and curing process of the prolonged release coated pellets.

Science.gov (United States)

Korasa, Klemen; Hudovornik, Grega; Vrečer, Franc

2016-10-10

Although process analytical technology (PAT) guidance has been introduced to the pharmaceutical industry just a decade ago, this innovative approach has already become an important part of efficient pharmaceutical development, manufacturing, and quality assurance. PAT tools are especially important in technologically complex operations which require strict control of critical process parameters and have significant effect on final product quality. Manufacturing of prolonged release film coated pellets is definitely one of such processes. The aim of the present work was to study the applicability of the at-line near-infrared spectroscopy (NIR) approach in the monitoring of pellet film coating and curing steps. Film coated pellets were manufactured by coating the active ingredient containing pellets with film coating based on polymethacrylate polymers (Eudragit® RS/RL). The NIR proved as a useful tool for the monitoring of the curing process since it was able to determine the extent of the curing and hence predict drug release rate by using partial least square (PLS) model. However, such approach also showed a number of limitations, such as low reliability and high susceptibility to pellet moisture content, and was thus not able to predict drug release from pellets with high moisture content. On the other hand, the at-line NIR was capable to predict the thickness of Eudragit® RS/RL film coating in a wide range (up to 40μm) with good accuracy even in the pellets with high moisture content. To sum up, high applicability of the at-line NIR in the monitoring of the prolonged release pellets production was demonstrated in the present study. The present findings may contribute to more efficient and reliable PAT solutions in the manufacturing of prolonged release dosage forms. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of Doping Concentration on the Structural and Optical Properties of Spin-Coated In-doped ZnO Thin Films Grown on Thermally Oxidized ZnO Film/ZnO Buffer Layer/Mica Substrate

Energy Technology Data Exchange (ETDEWEB)

Kim, Byunggu; Leem, Jae-Young [Inje University, Gimhae (Korea, Republic of)

2017-01-15

ZnO buffer layers were deposited on mica substrates using a sol-gel spin coating method. Then, a thin film of metallic Zn was deposited onto the ZnO buffer layer/mica substrate using a thermal evaporator, and the deposited Zn thin films were then thermally oxidized in a furnace at 500 ℃ for 2 h in air. Finally, In-doped ZnO (IZO) thin films with different In concentrations were grown on the oxidized ZnO film/ZnO buffer layer/mica substrates using the sol-gel spin-coating method. All the IZO films showed ZnO peaks with similar intensities. The full width at half maximum values of the ZnO (002) peak for the IZO thin films decreased with an increase in the In concentration to 1 at%, because the crystallinity of the films was enhanced. However, a further increase in the In concentration caused the crystal quality to degrade. This might be attributed to the fact that the higher In doping resulted in an increase in the number of ionized impurities. The Urbach energy (EU) values of the IZO thin film decreased with an increase in the In concentration to 1 at % because of the enhanced crystal quality of the films. The EU values for the IZO thin films increased with the In concentration from 1 at%to 3 at%, reflecting the broadening of localized band tail state near the conduction band edge of the films.

Effects of Doping Concentration on the Structural and Optical Properties of Spin-Coated In-doped ZnO Thin Films Grown on Thermally Oxidized ZnO Film/ZnO Buffer Layer/Mica Substrate

International Nuclear Information System (INIS)

Kim, Byunggu; Leem, Jae-Young

2017-01-01

ZnO buffer layers were deposited on mica substrates using a sol-gel spin coating method. Then, a thin film of metallic Zn was deposited onto the ZnO buffer layer/mica substrate using a thermal evaporator, and the deposited Zn thin films were then thermally oxidized in a furnace at 500 ℃ for 2 h in air. Finally, In-doped ZnO (IZO) thin films with different In concentrations were grown on the oxidized ZnO film/ZnO buffer layer/mica substrates using the sol-gel spin-coating method. All the IZO films showed ZnO peaks with similar intensities. The full width at half maximum values of the ZnO (002) peak for the IZO thin films decreased with an increase in the In concentration to 1 at%, because the crystallinity of the films was enhanced. However, a further increase in the In concentration caused the crystal quality to degrade. This might be attributed to the fact that the higher In doping resulted in an increase in the number of ionized impurities. The Urbach energy (EU) values of the IZO thin film decreased with an increase in the In concentration to 1 at % because of the enhanced crystal quality of the films. The EU values for the IZO thin films increased with the In concentration from 1 at%to 3 at%, reflecting the broadening of localized band tail state near the conduction band edge of the films.

Solution Coating of Pharmaceutical Nanothin Films and Multilayer Nanocomposites with Controlled Morphology and Polymorphism.

Science.gov (United States)

Horstman, Elizabeth M; Kafle, Prapti; Zhang, Fengjiao; Zhang, Yifu; Kenis, Paul J A; Diao, Ying

2018-03-28

Nanosizing is rapidly emerging as an alternative approach to enhance solubility and thus the bioavailability of poorly aqueous soluble active pharmaceutical ingredients (APIs). Although numerous techniques have been developed to perform nanosizing of API crystals, precise control and modulation of their size in an energy and material efficient manner remains challenging. In this study, we present meniscus-guided solution coating as a new technique to produce pharmaceutical thin films of nanoscale thickness with controlled morphology. We demonstrate control of aspirin film thickness over more than 2 orders of magnitude, from 30 nm to 1.5 μm. By varying simple process parameters such as the coating speed and the solution concentration, the aspirin film morphology can also be modulated by accessing different coating regimes, namely the evaporation regime and the Landau-Levich regime. Using ellipticine-a poorly water-soluble anticancer drug-as another model compound, we discovered a new polymorph kinetically trapped during solution coating. Furthermore, the polymorphic outcome can be controlled by varying coating conditions. We further performed layer-by-layer coating of multilayer nanocomposites, with alternating thin films of ellipticine and a biocompatible polymer, which demonstrate the potential of additive manufacturing of multidrug-personalized dosage forms using this approach.

Photocatalytic sterilization of TiO2 films coated on Al fiber

International Nuclear Information System (INIS)

Luo Li; Miao Lei; Tanemura, Sakae; Tanemura, Masaki

2008-01-01

Photocatalytic TiO 2 films were coated on Al fiber by sol-gel dip-coating method, and then annealed. The crystal structure and morphology of the films were performed by XRD, TEM and SEM. Photocatalytic sterilization of the films was investigated in O 2 atmosphere through purifying the aqueous solution with facultative aerobe (Bacillus cereus), aerobe (Pseudomonas aeruginosa) and anaerobe (Staphylococcus aureus, Enterococcus faecalis and Escherichia coli). In the presence of O 2 , it benefits to generate O 2 · - and ·OH at the first stage of the photocatalytic reaction, while the excess O 2 restrains the anaerobe from reproducing and accelerates the reproducing for the aerobe at the second stage of reaction. As a result, it was found that the crystal of TiO 2 films is anatase phase and the films have excellent sterilization effect against facultative aerobe and anaerobe. Nevertheless, it only decreased the bioactivity against aerobe in a short time

Improvement of Surface Properties of Inconel718 by HVOF Coating with WC-Metal Powder and by Laser Heat Treatment of the Coating

Directory of Open Access Journals (Sweden)

Hui Gon Chun

2015-01-01

Full Text Available High-velocity oxygen-fuel (HVOF thermal spray coating with WC-metal powder was carried out by using optimal coating process on an Inconel718 surface for improvement of the surface properties, friction, wear, and corrosion resistance. Binder metals such as Cr and Ni were completely melted and WC was decomposed partially to W2C and graphite during the high temperature (up to 3500°C thermal spraying. The melted metals were bonded with WC and other carbides and were formed as WC-metal coating. The graphite and excessively sprayed oxygen formed carbon oxide gases, and these gases formed porous coating by evolution of the gases. The surface properties were improved by HVOF coating and were improved further by CO2 laser heat treatment (LH. Wear resistance of In718 surface was improved by coating and LH at 25°C and an elevated temperature of 450°C, resulting in reduction of wear trace traces, and was further improved by LH of the coating in reducing wear depth. Corrosion resistance due to coating in sea water was improved by LH. HVOF coating of WC-metal powder on a metal surface and a LH of the coating were highly recommended for the improvement of In718 surface properties, the friction behavior, and wear resistance.

Microstructure and functional properties of the TiNi- and CuAl-based SMA thin films and coats produced by PVD technique

International Nuclear Information System (INIS)

Kolomytsev, V.; Musienko, R.; Nevdacha, V.; Panarin, V.; Pasko, A.; Cesari, E.; Segui, C.; Humbeeck, J. van

2000-01-01

The TiNi- and CuAl-based shape memory alloy thin films and wear/corrosion resistant surface coats have been produced by the ion-plasma deposition method with an arc dispersion of the cathode/target. This technique was widely used for production of the coats from a sprayed pure metal or a single-phase alloy. We have offered to use this process for dispersion of the heterophase alloys like shape memory alloys. The arguments for choosing of this technique are discussed with respect to creation of the conditions for preservation not only chemical composition, but also phase structure of an alloy in a covering, thus the shape memory/superelastic effects to be kept in a coat. (orig.)

Adhesion strength of nickel and zinc coatings with copper base electroplated in conditions of external stimulation by laser irradiance

Directory of Open Access Journals (Sweden)

V. V. Dudkina

2013-04-01

Full Text Available Purpose. The investigation of laser irradiance influence on the adhesion strength of nickel and zinc coatings with copper base and the research of initial stages of crystallization for nickel and zinc films. Methodology. Electrodeposition of nickel and zinc films from the standard sulphate electrolyte solutions was carried out on the laser-electrolytic installations, built on the basis of gas discharge CO2-laser and solid ruby laser KVANT-12. The adhesion strength of metal coatings with copper base are defined not only qualitatively using the method of meshing and by means of multiple bending, but also quantitatively by means of indention of diamond pyramid into the border line between coating and base of the side section. Spectrum microanalysis of the element composition of the border line “film and base” is carried out using the electronic microscope REMMA-102-02. Findings. Laser irradiance application of the cathode region in the process of electroplating of metal coatings enables the adhesion strength improvement of coating with the base. Experimental results of adhesive strength of the films and the spectrum analysis of the element composition for the border line between film and base showed that during laser-assisted electroplating the diffusion interaction between coating elements and the base metal surface takes place. As a result of this interaction the coating metal diffuses into the base metal, forming transition diffused layer, which enhances the improvement of adhesion strength of the coatings with the base. Originality. It is found out that ion energy increase in the double electric layer during interaction with laser irradiance affects cathode supersaturation at the stage of crystallization. Hence, it also affects the penetration depth of electroplated material ions into the base metal, which leads to the adhesion strength enhancement. Practical value. On the basis of research results obtained during the laser

Structured nanoporous surfaces from hybrid block copolymer micelle films with metal ions

International Nuclear Information System (INIS)

Kim, Minsoo P; Yi, Gi-Ra; Kim, Hyeong Jun; Kim, Bumjoon J

2015-01-01

We present a novel method for producing structured nanoporous thin films using block copolymer (BCP) micelles loaded with metallic ions. The BCP micellar thin films containing gold (Au) ions were prepared by spin-coating poly(styrene-block-4-vinylpyridine) (PS-b-P4VP) micelle solutions in which Au precursors (AuCl 4 − ) were selectively loaded onto the P4VP core. When the micellar films were exposed to cetyltrimethylammonium bromide (CTAB) solutions, the Au precursors were selectively extracted from the P4VP domains due to their strong electrostatic interaction with CTAB, leading to the formation of pores in the micelles. Consequently, regularly patterned nanoporous surfaces were formed. By controlling the molecular weight (M n ) of PS-b-P4VP and the amount of Au precursors (λ) that were loaded in the P4VP domains, the pore size and depth could be tuned precisely. In particular, when a sufficient amount of Au precursors was loaded (λ  ≥ 0.3), the porous surface nanostructure was well developed. In addition, the pore size and depth of the nanostructure increased as the λ value increased. For instance, when the λ value increased from 0.3 to 1.0, the pore size increased from 22.8 nm to 28.8 nm, and the pore depth increased from 2.1 nm to 3.2 nm. Interestingly, the transition from the nonporous structures to the porous structures in the micellar film could be reversibly controlled by adding and removing the Au precursors in the film. Moreover, our method for the preparation of nanoporous films can be extended to micellar film by incorporating other metal ions such as silver (Ag) and iron (Fe). (paper)

The preparation and corrosion behaviors of MAO coating on AZ91D with rare earth conversion precursor film

Energy Technology Data Exchange (ETDEWEB)

Cai Jingshun [Department of Chemistry, Zhejiang University, Zheda Road 38, Hangzhou, Zhejiang 310027 (China); Cao Fahe, E-mail: nelson_cao@zju.edu.cn [Department of Chemistry, Zhejiang University, Zheda Road 38, Hangzhou, Zhejiang 310027 (China); Chang Linrong; Zheng Junjun [Department of Chemistry, Zhejiang University, Zheda Road 38, Hangzhou, Zhejiang 310027 (China); Zhang Jianqing; Cao Chunan [Department of Chemistry, Zhejiang University, Zheda Road 38, Hangzhou, Zhejiang 310027 (China); State Key Laboratory for Corrosion and Protection, Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110016 (China)

2011-02-01

A novel kind of micro-arc oxidation (MAO) coating was prepared on magnesium alloy surface coated with rare earth conversion film (RE-film) in an alkaline aluminum oxidation electrolyte by AC power source. Inspection of scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) microspectroscopy, the structure and composition of MAO coating formed on AZ91D with RE-film under different applied voltages were investigated and the performance of the optimized MAO coating compared with the MAO coating directly formed on magnesium alloy. As the pretreatment of magnesium alloy with RE-film, the cerium oxides can be incorporated into the MAO coatings, reduce porosity of the MAO coating surface and enhance the thickness of MAO coating. These structure features and the cerium oxides incorporated into the MAO coating result in greatly improved corrosion resistance. Base on electrochemistry impedance spectroscopy (EIS) measurement, the electronic structure and composition analysis of the MAO coating, a double-layer structure, with a compact inner layer and a porous outer layer, of the coating was proposed for understanding its corrosion process.

The preparation and corrosion behaviors of MAO coating on AZ91D with rare earth conversion precursor film

International Nuclear Information System (INIS)

Cai Jingshun; Cao Fahe; Chang Linrong; Zheng Junjun; Zhang Jianqing; Cao Chunan

2011-01-01

A novel kind of micro-arc oxidation (MAO) coating was prepared on magnesium alloy surface coated with rare earth conversion film (RE-film) in an alkaline aluminum oxidation electrolyte by AC power source. Inspection of scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) microspectroscopy, the structure and composition of MAO coating formed on AZ91D with RE-film under different applied voltages were investigated and the performance of the optimized MAO coating compared with the MAO coating directly formed on magnesium alloy. As the pretreatment of magnesium alloy with RE-film, the cerium oxides can be incorporated into the MAO coatings, reduce porosity of the MAO coating surface and enhance the thickness of MAO coating. These structure features and the cerium oxides incorporated into the MAO coating result in greatly improved corrosion resistance. Base on electrochemistry impedance spectroscopy (EIS) measurement, the electronic structure and composition analysis of the MAO coating, a double-layer structure, with a compact inner layer and a porous outer layer, of the coating was proposed for understanding its corrosion process.

Thin films of metal-organic compounds and metal nanoparticle ...

Indian Academy of Sciences (India)

Optical limiting capability of the nanoparticle-embedded polymer film is demonstrated. Keywords. Polar crystal; uniaxial orientational order; thin film; second harmonic gen- eration; silver ... able content of metal nanoparticles would be of considerable value from an appli- ... polar chain and perpendicular to it [10].

Effect of nano-silver hydrogel coating film on deep partial thickness scald model of rabbit.

Science.gov (United States)

Xi, Peng; Li, Yan; Ge, Xiaojin; Liu, Dandan; Miao, Mingsan

2018-05-01

Observing the effect of nano-silver hydrogel coating film on deep partial thickness scald model of rabbit. We prepared boiling water scalded rabbits with deep II degree scald models and applied high, medium and low doses of nano-silver hydrogel coating film for different time and area. Then we compared the difference of burned paper weight before administration and after administration model burns, burn local skin irritation points infection, skin crusting and scabs from the time, and the impact of local skin tissue morphology. Rabbits deep II degree burn model successful modeling; on day 12, 18, high, medium and low doses of nano-silver hydrogel coating film significantly reduced skin irritation of rabbits infected with the integral value ( P  film group significantly decreased skin irritation, infection integral value ( P  film significantly reduced film rabbits' scalded skin crusting time ( P  film on the deep partial thickness burns has a significant therapeutic effect; external use has a significant role in wound healing.

Improvement of Ti-plasma coating on Ni-Ti shape memory alloy applying to implant materials and its evaluation

International Nuclear Information System (INIS)

Okuyama, Masaru; Endo, Jun; Take, Seisho; Itoi, Yasuhiko; Kambe, Satoshi

2002-01-01

Utilizing of Ni-Ti shape memory alloy for implant materials has been world-widely studied. it is, however, known that Ni-Ti alloy is easily attacked by chloride ion contained in body liquid. To prevent Ni dissolution, the authors tried to coat the alloy surface with titanium metal by means of plasma-spray coating method. The plasma coating films resulted in rather accelerating pitting corrosion because of their high porosity. Therefore, sealing of the porous films was required. In order to solve this problem and satisfy prolonged lifetime in the body, the authors tried to use the vacuum evaporation technique of titanium metal. Two types of Ti vacuum evaporation procedures were employed. The one was to cover a thin film on Ni-Ti alloy surface prior to massive Ti plasma spray coating. The other was to first coat plasma spray films on Ni-Ti alloy and then to cover them with vacuum evaporation films of Ti. Protective ability against pitting corrosion was examined by electrochemical polarization measurement in physiological solution and the coating films were characterized by microscopic and SEM observation and EPMA analysis. Vacuum evaporation thin films could not protect Ni-Ti alloy from pitting corrosion. In the case of plasma spray coating over the Ti vacuum evaporation thin film, the substrate Ni-Ti alloy could not be better protected. On the contrary, vacuum evaporation of Ti over the porous plasma spray coating layer remarkably improved corrosion protective performance

Reversed preparation of low-density poly(divinylbenzene/styrene) foam columns coated with gold films

Energy Technology Data Exchange (ETDEWEB)

Dai, Yinhai; Wang, Ni; Li, Yaling; Yao, Mengqi; Gan, Haibo; Hu, Wencheng, E-mail: huwc@uestc.edu.cn

2016-06-15

Highlights: • A reversed fabrication of low density foam columns coated with gold films was proposed. • The uniformity in thickness and purity of gold film are easy to be controlled. • A compact layer is prepared through an electrophoretic deposition method. • A low density (12 mg/cc) foam column coated with gold film is obtained. - Abstract: This work aims to fabricate low-density, porous, non-conductive, structural poly(divinylbenzene/styrene) foam columns by high-internal-phase emulsion templating. We prepare these non-conductive foam columns coated with a thin gold layer by electrochemical deposition and the reversed preparation technique. As expected, the density of the foam obtained through this novel method was about 12 mg cm{sup −3}, and the thickness of the gold coating was about 3 μm. We performed field emission scanning electron microscopy to morphologically and microstructurally characterize the products and X-ray diffraction and energy dispersive spectroscopy to determine the composition of the gold coating.

Low Temperature Metal Coating Method Final Report CRADA No. TSB-1155-95

Energy Technology Data Exchange (ETDEWEB)

Kang, Sang-Wook [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gabel, Howard [Innovative Technology, Inc., Santa Barbara, CA (United States)

2018-01-19

A new metal coating method, cidled KEM (kinetic energy metal.lization), demonstrated in the laboratory by lnovati, utilized fast-moving solid particIes entrained in a gas that are caused to fiow through a nozzIe to effect particle deposition on metal surfaces at room temperature conditions. This method (US Patent 5,795,626) was an attractive and viabIe alternative to the currentIy available high-temperature coating methods avaiIabIe. Since it differs significantly from existing metal coating technologies, a brief description of the method is incIuded here. The proposed method, KEM, achieves cohesive and adhesive metallurgical bonding through the high-speed coUision of powder with a substrate and the subsequent discharge of electrical charge at the substrate. Such coating is effected by entraining metal powder in a gas and accelerating this mixture through a supersonic nozzle. The gas/powder is directed towards the substrate to be coated. Collisions occur, initiaIly between the powder and the substrate, and, as the first Iayer of the coating forms, between the powder and the coating. During these collisions the powder is rapidly deformed, causing the exposure of fresh (oxide free) active metal surface. When these’active surfaces contact one another, they agglomerate and form true metaIIurgicaI bonds. The resultant coating has Iow porosity and high adhesive and cohesive strength. The formation of metaIIurgicaI bonds is potentiated by the discharge of electrical energy. This electrical energy is the result of triboeIectric charging of the particIes during acceleration and transit to the nozzIe. An advantage of the method is that it does not raise the temperature of the powder being appLiedor that of the substrate. Consequently, materials sensitive to high temperature may be applied without changing Me properties of the materkd or substrate.

Origin of Shear Stability and Compressive Ductility Enhancement of Metallic Glasses by Metal Coating

Science.gov (United States)

Sun, B. A.; Chen, S. H.; Lu, Y. M.; Zhu, Z. G.; Zhao, Y. L.; Yang, Y.; Chan, K. C.; Liu, C. T.

2016-01-01

Metallic glasses (MGs) are notorious for the poor macroscopic ductility and to overcome the weakness various intrinsic and extrinsic strategies have been proposed in past decades. Among them, the metal coating is regarded as a flexible and facile approach, yet the physical origin is poorly understood due to the complex nature of shear banding process. Here, we studied the origin of ductile enhancement in the Cu-coating both experimentally and theoretically. By examining serrated shear events and their stability of MGs, we revealed that the thin coating layer plays a key role in stopping the final catastrophic failure of MGs by slowing down shear band dynamics and thus retarding its attainment to a critical instable state. The mechanical analysis on interplay between the coating layer and shear banding process showed the enhanced shear stability mainly comes from the lateral tension of coating layer induced by the surface shear step and the bonding between the coating layer and MGs rather than the layer thickness is found to play a key role in contributing to the shear stability. PMID:27271435

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

Synthesis and characterization of ZnO nanostructures on noble-metal coated substrates

Energy Technology Data Exchange (ETDEWEB)

Dikovska, A.Og. [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Sofia 1784 (Bulgaria); Atanasova, G.B. [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev str., bl. 11, 1113 Sofia (Bulgaria); Avdeev, G.V. [Rostislaw Kaischew Institute of Physical Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev str., bl. 11, 1113 Sofia (Bulgaria); Nedyalkov, N.N. [Institute of Electronics, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee, Sofia 1784 (Bulgaria)

2016-06-30

Highlights: • ZnO nanostructures were fabricated on Au–Ag alloy coated silicon substrates by applying pulsed laser deposition. • Morphology of the ZnO nanostructures was related to the Au–Ag alloy content in the catalyst layer. • Increasing the Ag content in Au–Ag catalyst layer changes the morphology of the ZnO nanostructures from nanorods to nanobelts. - Abstract: In this work, ZnO nanostructures were fabricated on noble-metal (Au, Ag and Au–Ag alloys) coated silicon substrates by applying pulsed laser deposition. The samples were prepared at a substrate temperature of 550 °C, an oxygen pressure of 5 Pa, and a laser fluence of 2 J cm{sup −2} – process parameters usually used for deposition of smooth and dense thin films. The metal layer's role is substantial for the preparation of nanostructures. Heating of the substrate changed the morphology of the metal layer and, subsequently, nanoparticles were formed. The use of different metal particles resulted in different morphologies and properties of the ZnO nanostructures synthesized. The morphology of the ZnO nanostructures was related to the Au–Ag alloy's content of the catalyst layer. It was found that the morphology of the ZnO nanostructures evolved from nanorods to nanobelts as the ratio of Au/Ag in the alloy catalyst was varied. The use of a small quantity of Ag in the Au–Ag catalyst (Au{sub 3}Ag) layer resulted predominantly in the deposition of ZnO nanorods. A higher Ag content in the catalyst alloy (AuAg{sub 2}) layer resulted in the growth of a dense structure of ZnO nanobelts.

In-situ phosphatizing coatings for aerospace, OEM and coil coating applications

Science.gov (United States)

Neuder, Heather Aurelia

The current metal coating process is a multi-step process. The surface is cleaned, primered, dried and then painted. The process is labor intensive and time consuming. The wash primer is a conversion coating, which prepares metal surface for better paint adhesion. The wash primers currently used often contain hexavalent chromium (Cr6+), which seals the pores in the conversion coating. The presence of hexavalent chromium, a known carcinogen, and volatile organic compounds (VOCs) make waste disposal expensive and pose dangers to workers. The novel technique of in-situ phosphatizing coating (ISPC) is a single-step, chrome-free alternative to the present coating practice. Formulation of an ISPC involves predispersal of an in-situ phosphatizing reagent (ISPR) into the paint system to form a stable formulation. The ISPR reacts with the metal surface and bonds with the paint film simultaneously, which eliminates the need for a conversion coating. In acid catalyzed paint systems, such as polyester-melamine paints, the ISPR also catalyzes cross-linking reactions between the melamine and the polyester polyols. ISPCs are formulated using commercially available coating systems including: polyester-melamine, two-component epoxy, polyurethane and high-hydroxy content polyester-melamine coil coating. The ISPCs are applied to metal substrates and their performances are evaluated using electrochemical, thermal and standard American Society for Testing and Materials (ASTM) testing methods. In addition, ISPCs were designed and formulated based on: (1) phosphate chemistry, (2) polymer chemistry, (3) sol-gel chemistry, and (4) the ion-exchange principle. Organo-functionalized silanes, which serve as excellent coupling and dispersion agents, are incorporated into the optimized ISPC formula and evaluated using standard ASTM testing methods and electrochemical spectroscopy. Also, an ion-exchange pigment, which leads to better adhesion by forming a mixed metal silicate surface, is

Visible tunable lighting system based on polymer composites embedding ZnO and metallic clusters: from colloids to thin films

OpenAIRE

Truong, Thai Giang; Dierre, Benjamin; Grasset, Fabien; Saito, Noriko; Saito, Norio; Nguyen, Thi Kim Ngan; Takahashi, Kohsei; Uchikoshi, Tetsuo; Amela-Cortes, Marian; Molard, Yann; Cordier, St?phane; Ohashi, Naoki

2016-01-01

Abstract The development of phosphor devices free of heavy metal or rare earth elements is an important issue for environmental reasons and energy efficiency. Different mixtures of ZnO nanocrystals with Cs2Mo6I8(OOC2F5)6 cluster compound (CMIF) dispersed into polyvinylpyrrolidone matrix have been prepared by very simple and low cost solution chemistry. The resulting solutions have been used to fabricate highly transparent and luminescent films by dip coating free of heavy metal or rare earth ...

Transferred metal electrode films for large-area electronic devices

International Nuclear Information System (INIS)

Yang, Jin-Guo; Kam, Fong-Yu; Chua, Lay-Lay

2014-01-01

The evaporation of metal-film gate electrodes for top-gate organic field-effect transistors (OFETs) limits the minimum thickness of the polymer gate dielectric to typically more than 300 nm due to deep hot metal atom penetration and damage of the dielectric. We show here that the self-release layer transfer method recently developed for high-quality graphene transfer is also capable of giving high-quality metal thin-film transfers to produce high-performance capacitors and OFETs with superior dielectric breakdown strength even for ultrathin polymer dielectric films. Dielectric breakdown strengths up to 5–6 MV cm −1 have been obtained for 50-nm thin films of polystyrene and a cyclic olefin copolymer TOPAS ® (Zeon). High-quality OFETs with sub-10 V operational voltages have been obtained this way using conventional polymer dielectrics and a high-mobility polymer semiconductor poly[2,5-bis(3-tetradecylthiophene-2-yl)thieno[3,2-b]thiophene-2,5-diyl]. The transferred metal films can make reliable contacts without damaging ultrathin polymer films, self-assembled monolayers and graphene, which is not otherwise possible from evaporated or sputtered metal films

Laser-driven coating of vertically aligned carbon nanotubes with manganese oxide from metal organic precursors for energy storage

Science.gov (United States)

Pérez del Pino, A.; György, E.; Alshaikh, I.; Pantoja-Suárez, F.; Andújar, J. L.; Pascual, E.; Amade, R.; Bertran-Serra, E.

2017-09-01

Carbon nanotubes-transition metal oxide systems are intensively studied due to their excellent properties for electrochemical applications. In this work, an innovative procedure is developed for the synthesis of vertically aligned multi-walled carbon nanotubes (VACNTs) coated with transition metal oxide nanostructures. VACNTs are grown by plasma enhanced chemical vapor deposition and coated with a manganese-based metal organic precursor (MOP) film based on manganese acetate solution. Subsequent UV pulsed laser irradiation induces the effective heating-decomposition of the MOP leading to the crystallization of manganese oxide nanostructures on the VACNT surface. The study of the morphology, structure and composition of the synthesized materials shows the formation of randomly oriented MnO2 crystals, with few nanometers in size, and to their alignment in hundreds of nm long filament-like structures, parallel to the CNT’s long axis. Electrochemical measurements reveal a significant increase of the specific capacitance of the MnO2-VACNT system (100 F g-1) as compared to the initial VACNT one (21 F g-1).

Superhydrophobic films and methods for making superhydrophobic films

Science.gov (United States)

Aytug, Tolga; Paranthaman, Mariappan Parans; Simpson, John T.; Bogorin, Daniela Florentina

2017-09-26

This disclosure relates to methods that include depositing a first component and a second component to form a film including a plurality of nanostructures, and coating the nanostructures with a hydrophobic layer to render the film superhydrophobic. The first component and the second component can be immiscible and phase-separated during the depositing step. The first component and the second component can be independently selected from the group consisting of a metal oxide, a metal nitride, a metal oxynitride, a metal, and combinations thereof. The films can have a thickness greater than or equal to 5 nm; an average surface roughness (Ra) of from 90 to 120 nm, as measured on a 5 .mu.m.times.5 .mu.m area; a surface area of at least 20 m.sup.2/g; a contact angle with a drop of water of at least 120 degrees; and can maintain the contact angle when exposed to harsh conditions.

Si-based thin film coating on Y-TZP: Influence of deposition parameters on adhesion of resin cement

Energy Technology Data Exchange (ETDEWEB)

Queiroz, José Renato Cavalcanti, E-mail: joserenatocq@hotmail.com [Potiguar University, Department of Biotechnology, Natal (Brazil); Nogueira Junior, Lafayette [São Paulo State University, Department of Prosthodontics and Dental Materials, São José dos Campos (Brazil); Massi, Marcos [Federal University of São Paulo, Institute of Science and Technology, São José dos Campos (Brazil); Silva, Alecssandro de Moura; Bottino, Marco Antonio [São Paulo State University, Department of Prosthodontics and Dental Materials, São José dos Campos (Brazil); Sobrinho, Argemiro Soares da Silva [Technological Institute of Aeronautics, Department of Physics, São José dos Campos (Brazil); Özcan, Mutlu [University of Zurich, Dental Materials Unit, Center for Dental and Oral Medicine, Clinic for Fixed and Removable Prosthodontics and Dental Materials Science, Zurich (Switzerland)

2013-10-01

This study evaluated the influence of deposition parameters for Si-based thin films using magnetron sputtering for coating zirconia and subsequent adhesion of resin cement. Zirconia ceramic blocks were randomly divided into 8 groups and specimens were either ground finished and polished or conditioned using air-abrasion with alumina particles coated with silica. In the remaining groups, the polished specimens were coated with Si-based film coating with argon/oxygen magnetron discharge at 8:1 or 20:1 flux. In one group, Si-based film coating was performed on air-abraded surfaces. After application of bonding agent, resin cement was bonded. Profilometry, goniometry, Energy Dispersive X-ray Spectroscopy and Rutherford Backscattering Spectroscopy analysis were performed on the conditioned zirconia surfaces. Adhesion of resin cement to zirconia was tested using shear bond test and debonded surfaces were examined using Scanning Electron Microscopy. Si-based film coating applied on air-abraded rough zirconia surfaces increased the adhesion of the resin cement (22.78 ± 5.2 MPa) compared to those of other methods (0–14.62 MPa) (p = 0.05). Mixed type of failures were more frequent in Si film coated groups on either polished or air-abraded groups. Si-based thin films increased wettability compared to the control group but did not change the roughness, considering the parameters evaluated. Deposition parameters of Si-based thin film and after application of air-abrasion influenced the initial adhesion of resin cement to zirconia.

Si-based thin film coating on Y-TZP: Influence of deposition parameters on adhesion of resin cement

International Nuclear Information System (INIS)

Queiroz, José Renato Cavalcanti; Nogueira Junior, Lafayette; Massi, Marcos; Silva, Alecssandro de Moura; Bottino, Marco Antonio; Sobrinho, Argemiro Soares da Silva; Özcan, Mutlu

2013-01-01

This study evaluated the influence of deposition parameters for Si-based thin films using magnetron sputtering for coating zirconia and subsequent adhesion of resin cement. Zirconia ceramic blocks were randomly divided into 8 groups and specimens were either ground finished and polished or conditioned using air-abrasion with alumina particles coated with silica. In the remaining groups, the polished specimens were coated with Si-based film coating with argon/oxygen magnetron discharge at 8:1 or 20:1 flux. In one group, Si-based film coating was performed on air-abraded surfaces. After application of bonding agent, resin cement was bonded. Profilometry, goniometry, Energy Dispersive X-ray Spectroscopy and Rutherford Backscattering Spectroscopy analysis were performed on the conditioned zirconia surfaces. Adhesion of resin cement to zirconia was tested using shear bond test and debonded surfaces were examined using Scanning Electron Microscopy. Si-based film coating applied on air-abraded rough zirconia surfaces increased the adhesion of the resin cement (22.78 ± 5.2 MPa) compared to those of other methods (0–14.62 MPa) (p = 0.05). Mixed type of failures were more frequent in Si film coated groups on either polished or air-abraded groups. Si-based thin films increased wettability compared to the control group but did not change the roughness, considering the parameters evaluated. Deposition parameters of Si-based thin film and after application of air-abrasion influenced the initial adhesion of resin cement to zirconia.

SELF-ASSEMBLY CE OXIDE/ORGANOPOLYSILOXANE COMPOSITE COATINGS.

Energy Technology Data Exchange (ETDEWEB)

SUGAMA,T.; SABATINI,R.; GAWLIK,K.

2005-01-01

A self-assembly composite synthesis technology was used to put together a Ce(OH){sub 3}-dispersed poly-acetamide-acetoxyl methyl-propylsiloxane (PAAMPA) organometallic polymer. Three spontaneous reactions were involved; condensation, amidation, and acetoxylation, between the Ce acetate and aminopropylsilane triol (APST) at 150 C. An increase in temperature to 200 C led to the in-situ phase transformation of Ce(OH){sub 3} into Ce{sub 2}O{sub 3} in the PAAMPA matrix. A further increase to 250 C caused oxidative degradation of the PAAMPA, thereby generating copious fissures in the composite. We assessed the potential of Ce(OH){sub 3}/ and Ce{sub 2}O{sub 3}/ PAAMPA composite materials as corrosion-preventing coatings for carbon steel and aluminum. The Ce{sub 2}O{sub 3} composite coating displayed better performance in protecting both metals against NaCl-caused corrosion than did the Ce(OH){sub 3} composite. Using this coating formed at 200 C, we demonstrated that the following four factors played an essential role in further mitigating the corrosion of the metals: First was a minimum susceptibility of coating's surface to moisture; second was an enhanced densification of the coating layer; third was the retardation of the cathodic oxygen reduction reaction at the metal's corrosion sites due to the deposition of Ce{sub 2}O{sub 3} as a passive film over the metal's surface; and, fourth was its good adherence to metals. The last two factors contributed to minimizing the cathodic delamination of coating film from the metal's surface. We also noted that the affinity of the composite with the surface of aluminum was much stronger than that with steel. Correspondingly, the rate of corrosion of aluminum was reduced as much as two orders of magnitude by a nanoscale thick coating. In contrast, its ability to reduce the corrosion rate of steel was lower than one order of magnitude.

Sputtered indium oxide films

International Nuclear Information System (INIS)

Gillery, F.H.

1986-01-01

A method is described for depositing on a substrate multiple layer films comprising at least one primary layer of a metal oxide and at least one primary layer of a metal other than the metal of the oxide layer. The improvement described here comprises improving the adhesion between the metal oxide and metal layers by depositing between the layers an intermediate metal-containing layer having an affinity for both the metal and metal oxide layers. An article of manufacture is described comprising a nonmetallic substrate, and deposited thereon in any order: a. at least one coating layer of metal; b. at least one coating layer of an oxide of a metal other than the metal of the metal layer; and c. deposited between the metal and metal oxide layers an intermediate metal-containing layer having an affinity for both the metal and metal oxide layers

Antimicrobial Activity of TiO2 Nanoparticle-Coated Film for Potential Food Packaging Applications

Directory of Open Access Journals (Sweden)

Siti Hajar Othman

2014-01-01

Full Text Available Recent uses of titanium dioxide (TiO2 have involved various applications which include the food industry. This study aims to develop TiO2 nanoparticle-coated film for potential food packaging applications due to the photocatalytic antimicrobial property of TiO2. The TiO2 nanoparticles with varying concentrations (0–0.11 g/ 100 mL organic solvent were coated on food packaging film, particularly low density polyethylene (LDPE film. The antimicrobial activity of the films was investigated by their capability to inactivate Escherichia coli (E. coli in an actual food packaging application test under various conditions, including types of light (fluorescent and ultraviolet (UV and the length of time the film was exposed to light (one–three days. The antimicrobial activity of the TiO2 nanoparticle-coated films exposed under both types of lighting was found to increase with an increase in the TiO2 nanoparticle concentration and the light exposure time. It was also found that the antimicrobial activity of the films exposed under UV light was higher than that under fluorescent light. The developed film has the potential to be used as a food packaging film that can extend the shelf life, maintain the quality, and assure the safety of food.

Calcium and Zinc Containing Bactericidal Glass Coatings for Biomedical Metallic Substrates

Directory of Open Access Journals (Sweden)

Leticia Esteban-Tejeda

2014-07-01

Full Text Available The present work presents new bactericidal coatings, based on two families of non-toxic, antimicrobial glasses belonging to B2O3–SiO2–Na2O–ZnO and SiO2–Na2O–Al2O3–CaO–B2O3 systems. Free of cracking, single layer direct coatings on different biomedical metallic substrates (titanium alloy, Nb, Ta, and stainless steel have been developed. Thermal expansion mismatch was adjusted by changing glass composition of the glass type, as well as the firing atmosphere (air or Ar according to the biomedical metallic substrates. Formation of bubbles in some of the glassy coatings has been rationalized considering the reactions that take place at the different metal/coating interfaces. All the obtained coatings were proven to be strongly antibacterial versus Escherichia coli (>4 log.

Optical Thin Film Coating Having High Damage Resistance in Near-Stoichiometric MgO-Doped LiTaO3

Science.gov (United States)

Tateno, Ryo; Kashiwagi, Kunihiro

2008-08-01

Currently, High power and compact red, green, and blue (RGB) lasers are being considered for use in large screen laser televisions and reception-lobby projectors. Among these three laser sources, green semiconductor lasers are expensive and exhibit inferior performance in terms of the semiconductor material used, making it difficult to achieve a high output. In this study, we examined the use of our coating on MgO-doped LiTaO3, using a mirror coated with a multilayer film. Over a substrate, a Ta2O5 film was used to coat a high-refractive-index film layer, and a SiO2 film was used to coat a low-refractive-index film layer. To improve reflectivity, we designed the peak of the electric field intensity to be in the film layer with the low refractive index. As a result, the film endurance of 100 J/cm2 was obtained by one-on-one testing. With the nonlinear crystal material, the mirror without our coating exhibited a damage threshold of 33 J/cm2; however, after coating, this mirror demonstrated a higher damage threshold of 47 J/cm2. Thus, the film we fabricated using this technique is useful for improving the strength and durability of laser mirrors.

Preparation and voltammetric characterization of electrodes coated with Langmuir-Schaefer ultrathin films of Nafion®

Directory of Open Access Journals (Sweden)

Bertoncello Paolo

2003-01-01

Full Text Available Ultrathin films of Nafion® perfluorinated polymer were deposited on indium-tin oxide electrodes (ITO by using Langmuir-Schaefer (LS technique, after optimization of the subphase composition conditions. Morphological characteristics of these coatings were obtained by Atomic Force Microscopy (AFM. Nafion® LS films showed a good uniformity and complete coverage of the electrode surface, however a different organization degree of the polymer layer was evidenced with respect to thin films deposited by spin-coating. ITO electrodes modified with Nafion® LS coatings preconcentrate by ion-exchange electroactive cations, such as Ru[(NH36]3+, dissolved in diluted solutions. The electroactive species is retained by the Nafion® LS coated ITO also after transfer of the modified electrode into pure supporting electrolyte. This allowed the use of the ruthenium complex as voltammetric probe to test diffusion phenomena within the Nafion® LS films. Apparent diffusion coefficients (Dapp of Ru[(NH36]3+ incorporated in Nafion® LS films were obtained by voltammetric measurements. Dapp values decrease slightly by increasing the amount of ruthenium complex incorporated in the ultrathin film. They are significantly lower than values typical for recasted Nafion® films, in agreement with the highly condensed nature of the Nafion® LS fims.

Introduction of Nickel Coated Silicon Carbide Particles in Aluminum Metal Matrix Hardfaced by MIG/TIG Processes on Precoated Flux Layer

Directory of Open Access Journals (Sweden)

V. Kamburov

2018-03-01

Full Text Available The aim of the study was to investigate an aluminium metal matrix surface layer hardfaced by shielded gas metal arc welding processes applying either metal inert gas (MIG or tungsten inert gas (TIG, with standard wire filler onto the precoated flux layer - a baked resistant film containing electroless nickel coated micro/nano SiC particles. During baking, the components of the flux (MgCl2, NaCl, KCl and Na3AlF6 form a low melting eutectic, which: protects the hardfaced surface from oxidation, provides electrical conductance and keeps the particles on the surface during welding, as well as facilitates particles wettability and their interfacial bonding with the molten metal into the weld puddle.

COATING OF POLYMERIC SUBSTRATE CATALYSTS ON METALLIC SURFACES

Directory of Open Access Journals (Sweden)

H. HOSSEINI

2010-12-01

Full Text Available This article presents results of a study on coating of a polymeric substrate ca-talyst on metallic surface. Stability of coating on metallic surfaces is a proper specification. Sol-gel technology was used to synthesize adhesion promoters of polysilane compounds that act as a mediator. The intermediate layer was coated by synthesized sulfonated polystyrene-divinylbenzene as a catalyst for production of MTBE in catalytic distillation process. Swelling of catalyst and its separation from the metal surface was improved by i increasing the quantity of divinylbenzene in the resin’s production process and ii applying adhesion pro¬moters based on the sol-gel process. The rate of ethyl silicate hydrolysis was intensified by increasing the concentration of utilized acid while the conden¬sation polymerization was enhanced in the presence of OH–. Sol was formed at pH 2, while the pH should be 8 for the formation of gel. By setting the ratio of the initial concentrations of water to ethyl silicate to 8, the gel formation time was minimized.

Demonstration of surface plasmons in metal island films and the effect of the surrounding medium--An undergraduate experiment

Energy Technology Data Exchange (ETDEWEB)

Orfanides, P. [Department of Physics, The University of Memphis, Memphis, Tennessee 38152 (United States); Buckner, T. F. [Department of Physics, The University of Memphis, Memphis, Tennessee 38152 (United States); Buncick, M. C. [Department of Physics, The University of Memphis, Memphis, Tennessee 38152 (United States); Meriaudeau, F. [LE21, 12 rue de la fonderie, 71200 Le Creusot, (France); Ferrell, T. L. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2000-10-01

We present a demonstration of the surface plasmon phenomenon as it occurs in thin metal island films. The metal films are deposited on glass microscope slides. The effect of the surface plasmon resonance may be observed visually on the slide without further apparatus. Heating the film changes the shape of the islands and therefore the resonant frequency of the surface plasmon and changes the color of the film. Placing the film in a dielectric medium changes the resonance condition for the surface plasmon again and changes the color again. We show this by coating the slides with commercially available liquids with different indices of refraction. We present a theoretical model that assumes the islands are oblate spheroids. There are enough details given so that the equations can be programed and the theoretical optical absorbance can be reproduced. We also present a modification to the theory so that the shift in resonant frequency can be calculated when the spheroids are immersed in the index fluids. We describe our apparatus for making thin films and our optical spectrometer system. We then present optical absorbance measurements of thin films of both Ag and Au in air and in two liquids with different indices of refraction. (c) 2000 American Association of Physics Teachers.

A photochemical approach designed to improve the coating of nanoscale silver films onto food plastic wrappings intended to control bacterial hazards

International Nuclear Information System (INIS)

Mustatea, Gabriel; Vidal, Loïc; Calinescu, Ioan; Dobre, Alina; Ionescu, Mariana; Balan, Lavinia

2015-01-01

Plasmonic silver film was directly generated on a variety of substrates through a facile and environmentally friendly method, which involves a UV-photoreduction process without any reducing or stabilizing agent and requiring no thermal step. Top-coated films of unprotected silver nanoparticles (3–11 nm) were generated from hydroalcoholic AgNO 3 solution and directly on glass substrates or food packaging plastic wraps, low density polyethylene film, and polyvinyl chloride. The natural antibacterial activity of the material was evaluated. The correlation between silver migration and antimicrobial activity of silver-functionalized substrates against pure strains of gram-negative bacteria (Escherichia coli) and gram-positive bacteria (Staphylococcus aureus) was demonstrated. By way of illustration, food plastic wraps top-coated in this way exhibited a high antibacterial activity. The metal nanoparticle film obtained in this way was characterized and the influence of several parameters (fluence, exposure, silver nitrate concentration, and nature of the free radicals generator) on their formation was studied. Moreover, by shaping the actinic beam with an appropriate device, it is very easy to pattern the brown yellow silver nanofilm or to print messages in plain text

A photochemical approach designed to improve the coating of nanoscale silver films onto food plastic wrappings intended to control bacterial hazards

Energy Technology Data Exchange (ETDEWEB)

Mustatea, Gabriel [University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science (Romania); Vidal, Loïc [Institut de Sciences des Matériaux de Mulhouse, CNRS UMR 7361 (France); Calinescu, Ioan [University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science (Romania); Dobre, Alina; Ionescu, Mariana [National Research and Development Institute for Food Bioresources – IBA Bucharest (Romania); Balan, Lavinia, E-mail: lavinia.balan@uha.fr [Institut de Sciences des Matériaux de Mulhouse, CNRS UMR 7361 (France)

2015-01-15

Plasmonic silver film was directly generated on a variety of substrates through a facile and environmentally friendly method, which involves a UV-photoreduction process without any reducing or stabilizing agent and requiring no thermal step. Top-coated films of unprotected silver nanoparticles (3–11 nm) were generated from hydroalcoholic AgNO{sub 3} solution and directly on glass substrates or food packaging plastic wraps, low density polyethylene film, and polyvinyl chloride. The natural antibacterial activity of the material was evaluated. The correlation between silver migration and antimicrobial activity of silver-functionalized substrates against pure strains of gram-negative bacteria (Escherichia coli) and gram-positive bacteria (Staphylococcus aureus) was demonstrated. By way of illustration, food plastic wraps top-coated in this way exhibited a high antibacterial activity. The metal nanoparticle film obtained in this way was characterized and the influence of several parameters (fluence, exposure, silver nitrate concentration, and nature of the free radicals generator) on their formation was studied. Moreover, by shaping the actinic beam with an appropriate device, it is very easy to pattern the brown yellow silver nanofilm or to print messages in plain text.

A photochemical approach designed to improve the coating of nanoscale silver films onto food plastic wrappings intended to control bacterial hazards

Science.gov (United States)

Mustatea, Gabriel; Vidal, Loïc; Calinescu, Ioan; Dobre, Alina; Ionescu, Mariana; Balan, Lavinia

2015-01-01

Plasmonic silver film was directly generated on a variety of substrates through a facile and environmentally friendly method, which involves a UV-photoreduction process without any reducing or stabilizing agent and requiring no thermal step. Top-coated films of unprotected silver nanoparticles (3-11 nm) were generated from hydroalcoholic AgNO3 solution and directly on glass substrates or food packaging plastic wraps, low density polyethylene film, and polyvinyl chloride. The natural antibacterial activity of the material was evaluated. The correlation between silver migration and antimicrobial activity of silver-functionalized substrates against pure strains of gram-negative bacteria ( Escherichia coli) and gram-positive bacteria ( Staphylococcus aureus) was demonstrated. By way of illustration, food plastic wraps top-coated in this way exhibited a high antibacterial activity. The metal nanoparticle film obtained in this way was characterized and the influence of several parameters (fluence, exposure, silver nitrate concentration, and nature of the free radicals generator) on their formation was studied. Moreover, by shaping the actinic beam with an appropriate device, it is very easy to pattern the brown yellow silver nanofilm or to print messages in plain text.

Aging effects of plasma polymerized ethylenediamine (PPEDA) thin films on cell-adhesive implant coatings

International Nuclear Information System (INIS)

Testrich, H.; Rebl, H.; Finke, B.; Hempel, F.; Nebe, B.; Meichsner, J.

2013-01-01

Thin plasma polymer films from ethylenediamine were deposited on planar substrates placed on the powered electrode of a low pressure capacitively coupled 13.56 MHz discharge. The chemical composition of the plasma polymer films was analyzed by Fourier Transform Infrared Reflection Absorption Spectroscopy (FT-IRRAS) as well as by X-ray photoelectron spectroscopy (XPS) after derivatization of the primary amino groups. The PPEDA films undergo an alteration during the storage in ambient air, particularly, due to reactions with oxygen. The molecular changes in PPEDA films were studied over a long-time period of 360 days. Simultaneously, the adhesion of human osteoblast-like cells MG-63 (ATCC) was investigated on PPEDA coated corundum blasted titanium alloy (Ti-6Al-4V), which is applied as implant material in orthopedic surgery. The cell adhesion was determined by flow cytometry and the cell shape was analyzed by scanning electron microscopy. Compared to uncoated reference samples a significantly enhanced cell adhesion and proliferation were measured for PPEDA coated samples, which have been maintained after long-time storage in ambient air and additional sterilization by γ−irradiation. - Highlights: • Development of cell-adhesive nitrogen-rich coatings for biomedical applications. • Plasma polymer films from low pressure 13.56 MHz discharge in argon-ethylenediamine. • Enhanced osteoblast adhesion/proliferation on coated implant material (Ti-6Al-4V). • Despite film aging over 360 days the enhanced cell adhesion of the coating remains. • No influence of additional y-sterilization on the enhanced cell adhesion

High Critical Current Coated Conductors

Energy Technology Data Exchange (ETDEWEB)

Paranthaman, M. P.; Selvamanickam, V. (SuperPower, Inc.)

2011-12-27

One of the important critical needs that came out of the DOE’s coated conductor workshop was to develop a high throughput and economic deposition process for YBCO. Metal-organic chemical vapor deposition (MOCVD) technique, the most critical steps in high technical micro fabrications, has been widely employed in semiconductor industry for various thin film growth. SuperPower has demonstrated that (Y,Gd)BCO films can be deposited rapid with world record performance. In addition to high critical current density with increased film thickness, flux pinning properties of REBCO films needs to be improved to meet the DOE requirements for various electric-power equipments. We have shown that doping with Zr can result in BZO nanocolumns, but at substantially reduced deposition rate. The primary purpose of this subtask is to develop high current density MOCVD-REBCO coated conductors based on the ion-beam assisted (IBAD)-MgO deposition process. Another purpose of this subtask is to investigate HTS conductor design optimization (maximize Je) with emphasis on stability and protection issues, and ac loss for REBCO coated conductors.

Understanding Interfacial Alignment in Solution Coated Conjugated Polymer Thin Films

International Nuclear Information System (INIS)

Qu, Ge; Zhao, Xikang; Newbloom, Gregory M.; Zhang, Fengjiao; Mohammadi, Erfan

2017-01-01

Domain alignment in conjugated polymer thin films can significantly enhance charge carrier mobility. However, the alignment mechanism during meniscus-guided solution coating remains unclear. Furthermore, interfacial alignment has been rarely studied despite its direct relevance and critical importance to charge transport. In this study, we uncover a significantly higher degree of alignment at the top interface of solution coated thin films, using a donor–acceptor conjugated polymer, poly(diketopyrrolopyrrole-co-thiopheneco- thieno[3,2-b]thiophene-co-thiophene) (DPP2T-TT), as the model system. At the molecular level, we observe in-plane π–π stacking anisotropy of up to 4.8 near the top interface with the polymer backbone aligned parallel to the coating direction. The bulk of the film is only weakly aligned with the backbone oriented transverse to coating. At the mesoscale, we observe a well-defined fibril-like morphology at the top interface with the fibril long axis pointing toward the coating direction. Significantly smaller fibrils with poor orientational order are found on the bottom interface, weakly aligned orthogonal to the fibrils on the top interface. The high degree of alignment at the top interface leads to a charge transport anisotropy of up to 5.4 compared to an anisotropy close to 1 on the bottom interface. We attribute the formation of distinct interfacial morphology to the skin-layer formation associated with high Peclet number, which promotes crystallization on the top interface while suppressing it in the bulk. As a result, we further infer that the interfacial fibril alignment is driven by the extensional flow on the top interface arisen from increasing solvent evaporation rate closer to the meniscus front.

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.

The mechanism of the nano-CeO2 films deposition by electrochemistry method as coated conductor buffer layers

International Nuclear Information System (INIS)

Lu, Yuming; Cai, Shuang; Liang, Ying; Bai, Chuanyi; Liu, Zhiyong; Guo, Yanqun; Cai, Chuanbing

2015-01-01

Highlights: • Crack-free CeO 2 film thicker than 200 nm was prepared on NiW substrate by ED method. • Different electrochemical processes as hydroxide/metal mechanisms were identified. • The CeO 2 precursor films deposited by ED method were in nano-scales. - Abstract: Comparing with conventional physical vapor deposition methods, electrochemistry deposition technique shows a crack suppression effect by which the thickness of CeO 2 films on Ni–5 at.%W substrate can reach a high value up to 200 nm without any cracks, make it a potential single buffer layer for coated conductor. In the present work, the processes of CeO 2 film deposited by electrochemistry method are detailed investigated. A hydroxide reactive mechanism and an oxide reactive mechanism are distinguished for dimethyl sulfoxide and aqueous solution, respectively. Before heat treatment to achieve the required bi-axial texture performance of buffer layers, the precursor CeO 2 films are identified in nanometer scales. The crack suppression for electrochemistry deposited CeO 2 films is believed to be attributed to the nano-effects of the precursors

Hydroxyapatite coatings on titanium dioxide thin films prepared by pulsed laser deposition method

International Nuclear Information System (INIS)

Suda, Yoshiaki; Kawasaki, Hiroharu; Ohshima, Tamiko; Nakashima, Shouta; Kawazoe, Syuichi; Toma, Tetsuya

2006-01-01

Hydroxyapatite (HAp) coated on titanium dioxide (TiO 2 ) thin films has been developed to supplement the defects of both TiO 2 and HAp. Thin films have been prepared by pulsed laser deposition (PLD) method using HAp and HAp(10%) + TiO 2 targets. X-ray diffraction (XRD) shows that there are many small peaks of Ca 1 0(PO 4 ) 6 (OH) 2 crystal, and no impurity other than HAp is detected in HAp films prepared using pure HAp target. The composition ratio of the film was analyzed by X-ray photoelectron spectroscopy (XPS). HAp coatings on TiO 2 thin films have been prepared using HAp(10%) + TiO 2 targets. XRD and XPS measurements suggest that crystalline HAp + TiO 2 thin films are obtained by the PLD method using HAp(10%) + TiO 2 target

Spray-coated Cu2ZnSnS4 thin films for large-scale photovoltaic applications

DEFF Research Database (Denmark)

Engberg, Sara Lena Josefin; Murthy, Swathi; Mariño, Simón López

2017-01-01

The kesterite material, Cu2ZnSnS4 (CZTS), has in the preceding ten years been investigated and developed as a new Earth-abundant material for solar cells. The interest in this inorganic semiconductor originates in its optimal energy band gap of approx. 1.5 eV, high absorption coefficient...... that alkali metal chloride salts can also be dissolved in controllable amounts, which we have found enhances grain growth in the films during the subsequent annealing step. A Sono-tek spray-coating system with ultrasonic atomization is used. We investigate the effect of ink concentration, and spray...

A Scale-up Approach for Film Coating Process Based on Surface Roughness as the Critical Quality Attribute.

Science.gov (United States)

Yoshino, Hiroyuki; Hara, Yuko; Dohi, Masafumi; Yamashita, Kazunari; Hakomori, Tadashi; Kimura, Shin-Ichiro; Iwao, Yasunori; Itai, Shigeru

2018-04-01

Scale-up approaches for film coating process have been established for each type of film coating equipment from thermodynamic and mechanical analyses for several decades. The objective of the present study was to establish a versatile scale-up approach for film coating process applicable to commercial production that is based on critical quality attribute (CQA) using the Quality by Design (QbD) approach and is independent of the equipment used. Experiments on a pilot scale using the Design of Experiment (DoE) approach were performed to find a suitable CQA from surface roughness, contact angle, color difference, and coating film properties by terahertz spectroscopy. Surface roughness was determined to be a suitable CQA from a quantitative appearance evaluation. When surface roughness was fixed as the CQA, the water content of the film-coated tablets was determined to be the critical material attribute (CMA), a parameter that does not depend on scale or equipment. Finally, to verify the scale-up approach determined from the pilot scale, experiments on a commercial scale were performed. The good correlation between the surface roughness (CQA) and the water content (CMA) identified at the pilot scale was also retained at the commercial scale, indicating that our proposed method should be useful as a scale-up approach for film coating process.

Metal-oxide assisted surface treatment of polyimide gate insulators for high-performance organic thin-film transistors.

Science.gov (United States)

Kim, Sohee; Ha, Taewook; Yoo, Sungmi; Ka, Jae-Won; Kim, Jinsoo; Won, Jong Chan; Choi, Dong Hoon; Jang, Kwang-Suk; Kim, Yun Ho

2017-06-14

We developed a facile method for treating polyimide-based organic gate insulator (OGI) surfaces with self-assembled monolayers (SAMs) by introducing metal-oxide interlayers, called the metal-oxide assisted SAM treatment (MAST). To create sites for surface modification with SAM materials on polyimide-based OGI (KPI) surfaces, the metal-oxide interlayer, here amorphous alumina (α-Al 2 O 3 ), was deposited on the KPI gate insulator using spin-coating via a rapid sol-gel reaction, providing an excellent template for the formation of a high-quality SAM with phosphonic acid anchor groups. The SAM of octadecylphosphonic acid (ODPA) was successfully treated by spin-coating onto the α-Al 2 O 3 -deposited KPI film. After the surface treatment by ODPA/α-Al 2 O 3 , the surface energy of the KPI thin film was remarkably decreased and the molecular compatibility of the film with an organic semiconductor (OSC), 2-decyl-7-phenyl-[1]benzothieno[3,2-b][1]benzothiophene (Ph-BTBT-C 10 ), was increased. Ph-BTBT-C 10 molecules were uniformly deposited on the treated gate insulator surface and grown with high crystallinity, as confirmed by atomic force microscopy (AFM) and X-ray diffraction (XRD) analysis. The mobility of Ph-BTBT-C 10 thin-film transistors (TFTs) was approximately doubled, from 0.56 ± 0.05 cm 2 V -1 s -1 to 1.26 ± 0.06 cm 2 V -1 s -1 , after the surface treatment. The surface treatment of α-Al 2 O 3 and ODPA significantly decreased the threshold voltage from -21.2 V to -8.3 V by reducing the trap sites in the OGI and improving the interfacial properties with the OSC. We suggest that the MAST method for OGIs can be applied to various OGI materials lacking reactive sites using SAMs. It may provide a new platform for the surface treatment of OGIs, similar to that of conventional SiO 2 gate insulators.

Single crystalline metal films as substrates for graphene growth

Energy Technology Data Exchange (ETDEWEB)

Zeller, Patrick; Henss, Ann-Kathrin; Wintterlin, Joost [Department Chemie, Ludwig-Maximilians-Universitaet Muenchen (Germany); Weinl, Michael; Schreck, Matthias [Institut fuer Physik, Universitaet Augsburg (Germany); Speck, Florian; Ostler, Markus [Lehrstuhl fuer Technische Physik, Universitaet Erlangen-Nuernberg, Erlangen (Germany); Institut fuer Physik, Technische Universitaet Chemnitz (Germany); Seyller, Thomas [Institut fuer Physik, Technische Universitaet Chemnitz (Germany)

2017-11-15

Single crystalline metal films deposited on YSZ-buffered Si(111) wafers were investigated with respect to their suitability as substrates for epitaxial graphene. Graphene was grown by CVD of ethylene on Ru(0001), Ir(111), and Ni(111) films in UHV. For analysis a variety of surface science methods were used. By an initial annealing step the surface quality of the films was strongly improved. The temperature treatments of the metal films caused a pattern of slip lines, formed by thermal stress in the films, which, however, did not affect the graphene quality and even prevented wrinkle formation. Graphene was successfully grown on all three types of metal films in a quality comparable to graphene grown on bulk single crystals of the same metals. In the case of the Ni(111) films the originally obtained domain structure of rotational graphene phases could be transformed into a single domain by annealing. This healing process is based on the control of the equilibrium between graphene and dissolved carbon in the film. For the system graphene/Ni(111) the metal, after graphene growth, could be removed from underneath the epitaxial graphene layer by a pure gas phase reaction, using the reaction of CO with Ni to give gaseous Ni(CO){sub 4}. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Evaluating the effect of coating equipment on tablet film quality using terahertz pulsed imaging

DEFF Research Database (Denmark)

Haaser, Miriam; Naelapaa, Kaisa; Gordon, Keith C

2013-01-01

In this study, terahertz pulsed imaging (TPI) was employed to investigate the effect of the coating equipment (fluid bed and drum coater) on the structure of the applied film coating and subsequent dissolution behaviour. Six tablets from every batch coated with the same delayed release coating fo...

Effect of the External Lubrication Method for a Rotary Tablet Press on the Adhesion of the Film Coating Layer.

Science.gov (United States)

Kondo, Hisami; Toyota, Hiroyasu; Kamiya, Takayuki; Yamashita, Kazunari; Hakomori, Tadashi; Imoto, Junko; Kimura, Shin-Ichiro; Iwao, Yasunori; Itai, Shigeru

2017-01-01

External lubrication is a useful method which reduces the adhesion of powder to punches and dies by spraying lubricants during the tableting process. However, no information is available on whether the tablets prepared using an external lubrication system can be applicable for a film coating process. In this study, we evaluated the adhesion force of the film coating layer to the surface of tablets prepared using an external lubrication method, compared with those prepared using internal lubrication method. We also evaluated wettability, roughness and lubricant distribution state on the tablet surface before film coating, and investigated the relationship between peeling of the film coating layer and these tablet surface properties. Increasing lubrication through the external lubrication method decreased wettability of the tablet surface. However, no change was observed in the adhesion force of the film coating layer. On the other hand, increasing lubrication through the internal lubrication method, decreased both wettability of the tablet surface and the adhesion force of the film coating layer. The magnesium stearate distribution state on the tablet surface was assessed using an X-ray fluorescent analyzer and lubricant agglomerates were observed in the case of the internal lubrication method. However, the lubricant was uniformly dispersed in the external lubrication samples. These results indicate that the distribution state of the lubricant affects the adhesion force of the film coating layer, and external lubrication maintained sufficient lubricity and adhesion force of the film coating layer with a small amount of lubricant.

Metal coatings for laser fusion targets by electroplating

International Nuclear Information System (INIS)

Illige, J.D.; Yu, C.M.; Letts, S.A.

1980-01-01

Metal coated laser fusion targets must be dense, uniform spherically symmetric to within a few percent of their diameters and smooth to better than a few tenths of a micron. Electroplating offers some unique advantages including low temperature deposition, a wide choice of elements and substantial industrial plating technology. We have evaluatd electroless and electroplating systems for gold and copper, identified the factors responsible for small grain size, and plated glass microspheres with both metals to achieve smooth surfaces and highly symmetric coatings. We have developed plating cells which sustain the microspheres in continuous random motion during plating. We have established techniques for deposition of the initial conductive adherent layer on the glass microsphere surface. Coatings as thick as 15 μm have been made. The equipment is simple, relatively inexpensive and may be adopted for high volume production of laser fusion targets

Silica doped with lanthanum sol–gel thin films for corrosion protection

International Nuclear Information System (INIS)

Abuín, M.; Serrano, A.; Llopis, J.; García, M.A.; Carmona, N.

2012-01-01

We present here anticorrosive silica coatings doped with lanthanum ions for the protection of metallic surfaces as an alternative to chromate (VI)-based conversion coatings. The coatings were synthesized by the sol–gel method starting from silicon alkoxides and two different lanthanum precursors: La (III) acetate hydrate and La (III) isopropoxide. Artificial corrosion tests in acid and alkaline media showed their effectiveness for the corrosion protection of AA2024 aluminum alloy sheets for coating prepared with both precursors. The X-ray absorption Near Edge Structure and X-ray Absorption Fine Structure analysis of the coatings confirmed the key role of lanthanum in the structural properties of the coating determining its anticorrosive properties. - Highlights: ► Silica sol–gel films doped with lanthanum ions were synthesized. ► Films from lanthanum-acetate and La-alkoxide were prepared for comparison purposes. ► La-acetate is an affordable chemical reactive preferred for the industry. ► Films properties were explored by scanning electron microscopy and X-Ray absorption spectroscopy. ► An alternative to anticorrosive pre-treatments for metallic surfaces is suggested.

Polymer Nanocomposite Film with Metal Rich Surface Prepared by In Situ Single-Step Formation of Palladium Nanoparticles: An Interesting Way to Combine Specific Functional Properties

Directory of Open Access Journals (Sweden)

David Thompson

2016-10-01

Full Text Available This paper presents a continuous single-step route that permits preparation of a thermostable polymer/metal nanocomposite film and to combine different functional properties in a unique material. More precisely, palladium nanoparticles are in situ generated in a polyimide matrix thanks to a designed curing cycle which is applied to a polyamic acid/metal precursor solution cast on a glass plate. A metal-rich surface layer which is strongly bonded to the bulk film is formed in addition to homogeneously dispersed metal nanoparticles. This specific morphology leads to obtaining an optically reflective film. The metal nanoparticles act as gas diffusion barriers for helium, oxygen, and carbon dioxide; they induce a tortuosity effect which allows dividing the gas permeation coefficients by a factor near to 2 with respect to the neat polyimide matrix. Moreover, the ability of the in situ synthesized palladium nanoparticles to entrap hydrogen is evidenced. The nanocomposite film properties can be modulated as a function of the location of the film metal-rich surface with respect to the hydrogen feed. The synthesized nanocomposite could represent a major interest for a wide variety of applications, from specific coatings for aerospace or automotive industry, to catalysis applications or sensors.

Soybean oil in water-borne coatings and latex film formation study by AC impedance

Science.gov (United States)

Jiratumnukul, Nantana

Conventional coalescing agents such as butyl cellosolve, butyl carbitol, and TexanolRTM are widely use in the latex coatings industry to facilitate film formation at ambient temperature. Coalescent aids are composed of solvents with low evaporation rates. After water evaporates, coalescent aids would help soften polymer molecules and form continuous films, then gradually evaporates from the film. Coalescent aids, therefore, are considered as volatile organic compounds (VOC), which are of environmental concern. The main purpose of this research project was to prepare a fatty acid glycol ester from soybean oil and glycol (polyols). The soybean oil glycol ester can be used as a coalescent aid in latex paint formulation. The soybean oil glycol ester not only lowered the minimum film formation temperature of latex polymers and continuous film formed at ambient temperature, but also after it has facilitated film formation, does not substantially evaporate, but becomes part of the film. Soybean oil glycol esters, therefore, can reduce the VOC levels and facilitate film formation of latex paints. In the second part of this research AC-Impedance was used to investigate the efficiency of soybean oil coalescent aid in latex film formation relative to the conventional ones. The coating resistance showed that the efficiency of film formation was increased as a function of dry time. The coating resistance also exhibited the effect of soybean oil ester in latex film formation in the same fashion as a conventional coalescent aid, TexanolRTM.

Implementation of Carbon Thin Film Coatings in the Super Proton Synchrotron (SPS) for Electron Cloud Mitigation

CERN Document Server

Costa Pinto, P; Basso, T; Edwards, P; Mensi, M; Sublet, A; Taborelli, M

2014-01-01

Low Secondary Electron Yield (SEY) carbon thin films eradicate electron multipacting in accelerator beam pipes. Two magnetic cells of the SPS were coated with such material and installed. In total more than forty vacuum vessels and magnet interconnections were treated. The feasibility of the coating process was validated. The performance of the carbon thin film will be tested with LHC nominal beams after the end of the long shutdown 1. Particular attention will be drawn to the long term behaviour. This paper presents the sputtering techniques used to coat the different components; their characterization (SEY measurements on coupons, RF multipacting tests and pump down curves); and the technology to etch the carbon film in case of a faulty coating. The strategy to coat the entire SPS will also be described.

Process engineering of ceramic composite coatings for fuel cell systems

Energy Technology Data Exchange (ETDEWEB)

Li, G.; Kim, H.; Chen, M.; Yang, Q.; Troczynski, T. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Metals and Materials Engineering

2003-07-01

Researchers at UBCeram at the Department of Metals and Materials Engineering at the University of British Columbia have developed a technology to chemically bond composite sol-gel (CB-CSG) coating onto metallic surfaces of complex or concave shapes. The process has been optimized for electrically resistive coatings and corrosion-resistant coatings. The CSG is sprayed onto metallic surfaces and is heat-treated at 300 degrees C to partially dehydrate the hydroxides. The CSG film is then chemically bonded through reaction of active alumina with metal phosphates, such as aluminium phosphate. A new chromate-free process is being developed to address the issue of coatings porosity. The electrodeposition technique involves polymer particles mixed with suspended fine alumina particles which are co-deposited by electrophoretic means or by electrocoagulation. The composite e-coatings have excellent mechanical properties and are being considered as a protective coating for various components of fuel cell systems. 9 refs., 7 figs.

Functional patterned coatings by thin polymer film dewetting.

Science.gov (United States)

Telford, Andrew M; Thickett, Stuart C; Neto, Chiara

2017-12-01

An approach for the fabrication of functional polymer surface coatings is introduced, where micro-scale structure and surface functionality are obtained by means of self-assembly mechanisms. We illustrate two main applications of micro-patterned polymer surfaces obtained through dewetting of bilayers of thin polymer films. By tuning the physical and chemical properties of the polymer bilayers, micro-patterned surface coatings could be produced that have applications both for the selective attachment and patterning of proteins and cells, with potential applications as biomaterials, and for the collection of water from the atmosphere. In all cases, the aim is to achieve functional coatings using approaches that are simple to realize, use low cost materials and are potentially scalable. Copyright © 2017 Elsevier Inc. All rights reserved.

Radioisotope albedo method for measuring thickness of polymers coatings on metal basis

International Nuclear Information System (INIS)

Kapranov, B.I.; Myakin'kova, L.V.; Shaverin, V.A.

1986-01-01

Theoretical analysis of albedo thickness measuring of polymer coating-metal composite has been made and experimental studies of the range of tested thicknesses of polymer coating when different metal bases and radiation sources are used have been conducted. It is shown that the thickness of polymer coating on metal can be measured using backscattered γ-radiation in the energy range of 20-120 keV at the error 0.15-0.8 mm, at that, for thickness up to 23 mm the use of 147 Pm isotope can be defined as the optimum one; for thicknesses up to 40 mm 241 Am should be used; at thicknesses up to 60 mm - 57 Co. The AGAT-1 albedo gamma thickness gage, designed for measuring thickness of fiber glass coating up to 20 mm on metal base, is described

21 CFR 888.3565 - Knee joint patellofemorotibial metal/polymer porous-coated uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint patellofemorotibial metal/polymer... Devices § 888.3565 Knee joint patellofemorotibial metal/polymer porous-coated uncemented prosthesis. (a) Identification. A knee joint patellofemorotibial metal/polymer porous-coated uncemented prosthesis is a device...

Tumeric oil as the antioxidation agent in edible coating film

Science.gov (United States)

Ahmad, N. A.; Sharif, Z. I. M.; Jai, J.; Yusof, N. M.; Mustapha, F. A.

2018-03-01

Turmeric oil (TO) has been studied for its potential as an antioxidation agent in starch edible coating for fresh cut apples and its degree of oxidation was analysed. TO incorporate with starch edible coating was examined using FT-IR Spectroscopy to determine the presence of secondary metabolites. The presence of alcohol and aromatic ring in the edible coating film proved that the secondary metabolites from TO were existed. The fresh cut apples were underwent the sensory test and six out of ten panellist concluded that coated fresh cut apples have good appearance and surface colour. Fresh cut apples were coated with edible coating incorporated with different concentrations of TO (uncoated, 0μL, 5μL, 10μL, 15μL. Percentage weight loss for 15μL were the least which were 1.98% (day 6) and 3.95% (day 12). Colour measurement were done for few days and it shows that the total colour difference (ΔΕ) for 15μL were the lowest. Thus, the oxidation activities for 15μL is the slowest compared to the others. These can be proved through the degree of oxidation analysis using UV-Vis spectroscopy. Uncoated fresh cut apples have the highest degree of oxidation while those with 15μL have the lowest. This study can be illustrated that the oxidation activities of fresh cut apples could be postponed using edible film incorporated with TO.

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.)

Preparation and Characterization of FC Films Coated on PET Substrates by RF Magnetron Sputtering

Directory of Open Access Journals (Sweden)

Huang Mei-lin

2018-01-01

Full Text Available Fluorocarbon (FC films were prepared on polyethylene terephthalate (PET plates and PET fabrics respectively by a radiofrequency (RF magnetron sputtering technique using polytetrafluoroethylene (PTFE as a target. Scanning electron microscope and X-ray photoelectron spectroscopy were used to investigate the morphology, structure and composition of the obtained FC films. The hydrophobicity and uvioresistant properties of the FC film coated fabric were studied. The results show that the FC films were successfully deposited on the PET substrates by a RF magnetron sputtering. The deposited films are made up of four components -CF3, -CF2-, CF- and -C-. The proportions of the four components and surface morphologies of the deposited films vary with the sputtering conditions. Compared with the original fabric samples, the hydrophobicity of the FC film coated fabrics is quite good and improved significantly.

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.

Evaluation of Plasma Spray hydroxy Apatite Coatings on Metallic Materials

International Nuclear Information System (INIS)

Take, S.; Mitsul, K.; Kasahara, M.; Sawal, R.; Izawa, S.; Nakayama, M.; Itoi, Y.

2007-01-01

Biocompatible Hydroxy apatite (HAp) coatings on metallic substrate by plasma spray techniques have been developed. Long-term credibility of plasma spray HAp coatings has been evaluated in physiological saline by electrochemical measurements. It was found that the corrosion resistance of SUS316L based HAp/Ti combined coatings was excellent even after more than 10 weeks long-term immersion. It was shown that postal heat treatment improved both the crystallinity and corrosion resistance of HAp. By lowering cooling rate during heat treatment process, less cracks produced in HAp coating layer, which lead to higher credibility of HAp during immersion in physiological saline. The ICP results showed that the dissolution level of substrate metallic ions was low and HAp coatings produced in this research can be acceptable as biocompatible materials. Also, the concentration of dissolved ions from HAp coatings with postal heat treatment was lower compared to those from samples without postal heat treatment. The adherence of HAp coatings with Ti substrate and other mechanical properties were also assessed by three-point bending test. The poor adhesion of HAp coating to titanium substrate can be improved by introducing a plasma spray titanium intermediate layer

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

Anti-listerial activity of a polymeric film coated with hybrid coatings doped with Enterocin 416K1 for use as bioactive food packaging.

Science.gov (United States)

Iseppi, Ramona; Pilati, Francesco; Marini, Michele; Toselli, Maurizio; de Niederhäusern, Simona; Guerrieri, Elisa; Messi, Patrizia; Sabia, Carla; Manicardi, Giuliano; Anacarso, Immacolata; Bondi, Moreno

2008-04-30

In this study, Enterocin 416K1, a bacteriocin produced by Enterococcus casseliflavus IM 416K1, was entrapped in an organic-inorganic hybrid coating applied to a LDPE (low-density polyethylene) film for its potential use in the active food packaging field. The antibacterial activity of the coated film was evaluated against Listeria monocytogenes NCTC 10888 by qualitative modified agar diffusion assay, quantitative determination in listeria saline solution suspension and direct contact with artificially contaminated food samples (frankfurters and fresh cheeses) stored at room and refrigeration temperatures. All investigations demonstrated that enterocin-activated coatings have a good anti-listeria activity. Qualitative tests showed a clear zone of inhibition in the indicator lawn in contact with and around the coated film. During the quantitative antibacterial evaluation the L. monocytogenes viable counts decreased to 1.5 log units compared to the control. The inhibitory capability was confirmed also in food-contact assays. In all food samples packed with coated films we observed a significant decrease in L. monocytogenes viable counts in the first 24 h compared to the control. This difference was generally maintained up to the seventh day and then decreased, with the exception of the cheese samples stored at refrigeration temperature.

Ion assisted deposition of refractory oxide thin film coatings for improved optical and structural properties

International Nuclear Information System (INIS)

Sahoo, N.K.; Thakur, S.; Bhattacharyya, D.; Das, N.C.

1999-03-01

Ion assisted deposition technique (IAD) has emerged as a powerful tool to control the optical and structural properties of thin film coatings. Keeping in view the complexity of the interaction of ions with the films being deposited, sophisticated ion sources have been developed that cater to the need of modern optical coatings with stringent spectral and environmental specifications. In the present work, the results of ion assisted deposition (IAD) of two commonly used refractory oxides, namely TiO 2 and ZrO 2 , using cold cathode ion source (CC-102R) are presented. Through successive feedback and calibration techniques, various ion beams as well as deposition parameters have been optimized to achieve the best optical and structural film properties in the prevalent deposition geometry of the coating system. It has been possible to eliminate the unwanted optical and structural inhomogeneities from these films using and optimized set of process parameters. Interference modulated spectrophotometric and phase modulated ellipsometric techniques have been very successfully utilized to analyze the optical and structural parameters of the films. Several precision multilayer coatings have been developed and are being used for laser and spectroscopic applications. (author)

Antimicrobial activity of lauric arginate-coated polylactic acid films against Listeria monocytogenes and Salmonella typhimurium on cooked sliced ham.

Science.gov (United States)

Theinsathid, Pornpun; Visessanguan, Wonnop; Kruenate, Jittiporn; Kingcha, Yutthana; Keeratipibul, Suwimon

2012-02-01

A novel type of environmentally friendly packaging with antibacterial activity was developed from lauric arginate (LAE)-coating of polylactic acid (PLA) films after surface activation using a corona discharge. Scanning electron microscopy (SEM)-based analysis of the LAE/PLA films confirmed the successful coating of LAE on the PLA surface. The mechanical properties of the LAE/PLA films with different levels of LAE-coating (0% to 2.6%[w/w]) were essentially the same as those of the neat PLA film. The antibacterial activity of the LAE/PLA films against Listeria monocytogenes and Salmonella enterica Serovar Typhimurium (S. Typhimurium) was confirmed by a qualitative modified agar diffusion assay and quantitative JIS Z 2801:2000 method. Using the LAE/PLA film as a food-contact antimicrobial packaging for cooked cured ham, as a model system, suggested a potential application to inhibit L. monocytogenes and S. Typhimurium on ham with a 0.07% (w/w) LAE coating on the PLA when high transparency is required, as evidenced from the 2 to 3 log CFU/tested film lower pathogen growth after 7 d storage but even greater antibacterial activity is obtained with a LAE coating level of 2.6% (w/w) but at the cost of a reduced transparency of the finished product. This article shows how we can simply develop functional green packaging of PLA for food with effective and efficient antimicrobial activity by use of LAE coating on the surface via corona discharge. The effectiveness of an innovative antimicrobial LAE-coated PLA film against foodborne pathogens was demonstrated. Importantly, the application of the LAE to form the LAE-coated PLA film can be customized within current film manufacturing lines. © 2012 Institute of Food Technologists®

The development of pulsed ion sources with explosive ions emission for deposition of films and coatings with ion and electron mixing

International Nuclear Information System (INIS)

Korenev, S.

1998-01-01

The development of pulsed ion sources with explosive ion emission for deposition of films and coatings with ion and electron mixing is considered in the report. The deposition of films and coatings with high hardness and high resistance on the basis using this source on the working voltage 50--100 kV is presented. The deposition of TiB(2), W and other films is discussed and comparison with other results. The experimental results of pulsed electron/ion mixing are considered. The main characteristics of these films and coating are considered. The cluster mechanism of deposition of films and coatings are discussed. The main question of structure of these films on the basis of surface cluster fractal structure is suggested and discussed. The study of structure of these films showed the new kind of structure of these films and coatings

Quantitative analysis and metallic coating thickness measurements by X-ray fluorescence

International Nuclear Information System (INIS)

Negrea, Denis; Ducu, Catalin; Malinovschi, Viorel; Moga, Sorin; Boicea, Niculae

2009-01-01

This work deals with the use of X-ray fluorescence (XRF) for determining the concentration and the coating thickness on metallic samples. The analysis method presented here may also be applicable to other coatings, providing that the elemental nature of the coating and substrate are compatible with the technical aspects of XRF, such as the absorption coefficient of the system, primary radiation, fluorescent radiation and type of detection. For the coating thickness measurement it was used the substrate-line attenuation method and an algorithm was developed. Its advantage relies in the fact that no special calibration with standard samples having different layer thickness is needed. The samples used for evaluation were metallic pieces of iron with zinc-nickel coatings of different thickness obtained by electrochemical deposition. (authors)

The importance of spinning speed in fabrication of spin-coated organic thin film transistors: Film morphology and field effect mobility

International Nuclear Information System (INIS)

Kotsuki, Kenji; Tanaka, Hiroshige; Obata, Seiji; Stauss, Sven; Terashima, Kazuo; Saiki, Koichiro

2014-01-01

We have investigated the film morphology and the field effect mobility of 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) thin films which were formed by spin coating on the SiO 2 substrate with solution-processed graphene electrodes. The domain size and the density of aggregates in the C8-BTBT film showed the same dependence on the spinning speed. These competitive two factors (domain size and density of aggregates) give an optimum spinning speed, at which the field effect mobility of C8-BTBT transistor showed a maximum (2.6 cm 2 /V s). This result indicates the importance of spinning speed in the fabrication of solution processed organic thin film transistors by spin coating.

Corrosion performance of some titanium-based hard coatings

International Nuclear Information System (INIS)

Matthes, B.; Broszeit, E.; Aromaa, J.; Ronkainen, H.; Hannula, S.P.; Leyland, A.; Matthews, A.

1991-01-01

Tools and machine parts which could benefit from wear-resistant titanium-based hard films are often subject to corrosive environments. Physically vapour-deposited coatings frequently exhibit porosity and even small defects, which can cause rapid local corrosion of the substrate material; there is therefore a requirement for dense and chemically inert coatings. This paper presents corrosion data for titanium-based hard coatings such as TiN, (Ti, Al)N, Ti(B, N) and TiB 2 and also for multilayered structures where additional aluminium-based insulating surface layers (AlN and Al 2 O 3 ) were deposited. The corrosion resistance and porosity of the films were analysed by electrochemical techniques. The degree of metallic bonding can play a significant role in influencing the corrosion resistance of refractory transition-metal-based ceramic coatings. Here we demonstrate that, under potentiodynamic corrosion test conditions, resistance to corrosive attack was relatively poor for TiB 2 , better for (Ti, Al)N and Ti(B, N) and best for TiN. It is also shown that applying the additional protective aluminium-based insulating surface layers on the coating can further improve corrosion resistance. (orig.)

Indium Sulfide and Indium Oxide Thin Films Spin-Coated from Triethylammonium Indium Thioacetate Precursor for n-Channel Thin Film Transistor

Energy Technology Data Exchange (ETDEWEB)

Tung, Duy Dao; Jeong, Hyun Dam [Chonnam Natioal University, Gwangju (Korea, Republic of)

2014-09-15

The In{sub 2}S{sub 3} thin films of tetragonal structure and In{sub 2}O{sub 3} films of cubic structure were synthesized by a spin coating method from the organometallic compound precursor triethylammonium indium thioacetate ([(Et){sub 3}NH]+ [In(SCOCH{sub 3}){sub 4}]''-; TEA-InTAA). In order to determine the electron mobility of the spin-coated TEA-InTAA films, thin film transistors (TFTs) with an inverted structure using a gate dielectric of thermal oxide (SiO{sub 2}) was fabricated. These devices exhibited n-channel TFT characteristics with a field-effect electron mobility of 10.1 cm''2 V''-1s''-1 at a curing temperature of 500 o C, indicating that the semiconducting thin film material is applicable for use in low-cost, solution-processed printable electronics.

Non-hydrolytic metal oxide films for perovskite halide overcoating and stabilization

Science.gov (United States)

Martinson, Alex B.; Kim, In Soo

2017-09-26

A method of protecting a perovskite halide film from moisture and temperature includes positioning the perovskite halide film in a chamber. The chamber is maintained at a temperature of less than 200 degrees Celsius. An organo-metal compound is inserted into the chamber. A non-hydrolytic oxygen source is subsequently inserted into the chamber. The inserting of the organo-metal compound and subsequent inserting of the non-hydrolytic oxygen source into the chamber is repeated for a predetermined number of cycles. The non-hydrolytic oxygen source and the organo-metal compound interact in the chamber to deposit a non-hydrolytic metal oxide film on perovskite halide film. The non-hydrolytic metal oxide film protects the perovskite halide film from relative humidity of greater than 35% and a temperature of greater than 150 degrees Celsius, respectively.

PEEK (polyether-ether-ketone)-coated nitinol wire: Film stability for biocompatibility applications

Science.gov (United States)

Sheiko, Nataliia; Kékicheff, Patrick; Marie, Pascal; Schmutz, Marc; Jacomine, Leandro; Perrin-Schmitt, Fabienne

2016-12-01

High quality biocompatible poly-ether-ether-ketone (PEEK) coatings were produced on NiTi shape memory alloy wires using dipping deposition from colloidal aqueous PEEK dispersions after substrate surface treatment. The surface morphology and microstructure were investigated by Scanning Electron Microscopy at every step of the process from the as-received Nitinol substrate to the ultimate PEEK-coated NiTi wire. Nanoscratch tests were carried out to access the adhesive behavior of the polymer coated film to the NiTi. The results indicate that the optimum process conditions in cleaning, chemical etching, and electropolishing the NiTi, were the most important and determining parameters to be achieved. Thus, high quality PEEK coatings were obtained on NiTi wires, straight or curved (even with a U-shape) with a homogeneous microstructure along the wire length and a uniform thickness of 12 μm without any development of cracks or the presence of large voids. The biocompatibility of the PEEK coating film was checked in fibrobast cultured cells. The coating remains stable in biological environment with negligible Ni ion release, no cytotoxicity, and no delamination observed with time.