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Sample records for ni-mo coatings produced

  1. Characterisation of electrodeposited and heat-treated Ni-Mo-P coatings

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Regis L.; Casciano, Paulo N.S.; Correia, Adriana N.; Lima-Neto, Pedro de, E-mail: pln@ufc.br [Departamento de Quimica Analitica e Fisico-Quimica, Universidade Federal do Ceara, Fortaleza, CE (Brazil)

    2012-07-01

    The electrodeposition, hardness and corrosion resistance properties of Ni-Mo-P coatings were investigated. Characterisations of the electrodeposited coatings were carried out using scanning electron microscopy, X-ray diffraction and energy dispersive X-ray analysis techniques. Corrosion tests were performed at room temperature in 10-1 mol dm-3 NaCl solutions and by potentiodynamic linear polarisation. Amorphous Ni-Mo-P coatings were successfully obtained by electrodeposition using direct current. The coating composition showed to be dependent on the bath composition, current density and bath temperature. Both P and Mo contents contribute for the hardness properties of the Ni-Mo-P coatings and the absence of cracks is a requirement to produce electrodeposited Ni-Mo-P coatings with good hardness properties. The hardness values increase with heat-treatment temperature due to the precipitation of Ni, Ni{sub 3}P and NiMo phases during the heat treatment. The corrosion resistance of the electrodeposited Ni-Mo-P amorphous coatings increases with P content in the layer. Among the electrodeposited Ni-Mo-P amorphous coatings, Ni{sub 78}Mo{sub 10}P{sub 12} presented the best hardness and corrosion-resistance properties. The results showed that the addition of P is beneficial for the hardness and corrosion resistance properties of the Ni-Mo-based coatings. (author)

  2. Electrodeposition and characterization of Ni-Mo-ZrO2 composite coatings

    Science.gov (United States)

    Laszczyńska, A.; Winiarski, J.; Szczygieł, B.; Szczygieł, I.

    2016-04-01

    Ni-Mo-ZrO2 composite coatings were produced by electrodeposition technique from citrate electrolytes containing dispersed ZrO2 nanopowder. The influence of deposition parameters i.e. concentration of molybdate and ZrO2 nanoparticles in the electrolyte, bath pH and deposition current density on the composition and surface morphology of the coating has been investigated. The structure, microhardness and corrosion properties of Ni-Mo-ZrO2 composites with different molybdenum and ZrO2 content have been also examined. It was found that ZrO2 content in the deposit is increased by rising the nanoparticles concentration in the plating solution up to 20 g dm-3. An increase in molybdate concentration in the electrolyte affects negatively the amount of codeposited ZrO2 nanoparticles. The correlation between the deposition current efficiency and ZrO2 content in the composite coating has been also observed. A decrease in deposition current efficiency leads to deposition of Ni-Mo-ZrO2 composite with low nanoparticles content. This may be explained by formation of higher amounts of gas bubbles on the cathode surface, which prevent the adsorption of ZrO2 nanoparticles on the growing deposit. The XRD analysis revealed that all the studied Ni-Mo-ZrO2 coatings were composed of a single, nanocrystalline phase with FCC structure. It was found that the incorporation of ZrO2 nanoparticles into Ni-Mo alloy matrix affects positively the microhardness and also slightly improves the corrosion properties of Ni-Mo alloy coating.

  3. Morphological, structural, microhardness and corrosion characterisations of electrodeposited Ni-Mo and Cr coatings

    National Research Council Canada - National Science Library

    Lima-Neto, Pedro de; Correia, Adriana N; Vaz, Gustavo L; Casciano, Paulo N. S

    2010-01-01

    The corrosion resistance of electrodeposited Cr and Ni-Mo coatings and the influence of heat treatment on the crystallographic structure, morphology and microhardness properties were investigated here...

  4. Morphological, structural, microhardness and corrosion characterisations of electrodeposited Ni-Mo and Cr coatings

    Energy Technology Data Exchange (ETDEWEB)

    Lima-Neto, Pedro de; Correia, Adriana N.; Vaz, Gustavo L.; Casciano, Paulo N.S., E-mail: pln@ufc.b [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Quimica Analitica e Fisico-Quimica

    2010-07-01

    The corrosion resistance of electrodeposited Cr and Ni-Mo coatings and the influence of heat treatment on the crystallographic structure, morphology and microhardness properties were investigated here. The characterisations were carried out using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX) techniques. Corrosion tests were performed at room temperature in 10{sup -1} mol dm{sup -3} NaCl solutions and by potentiodynamic linear polarization technique. The Mo content in the layer and current efficiency increased with the molybdate ion concentration in the plating solution, while the surface morphology evolved from rough and homogeneous to cracked surface with the increase of the amount of Mo in the layer. The electrochemical corrosion tests showed that the Cr coatings have better corrosion resistance than the Ni-Mo coatings in chloride medium and that all the studied coatings corrode in chloride medium. Ni-13Mo coating has the nobler corrosion behavior among the studied Ni-Mo coatings. The microhardness of the Ni-13Mo coatings increased as the annealing temperature increased which is related with the precipitation of Ni, Ni{sub 4}Mo and NiMo phases during the heat treatment of this coating. Ni-13Mo coating is a potential substitute for chromium coating in industrial applications when operating at temperatures higher than 100 deg C and good microhardness properties are required. (author)

  5. NiMo-sulfide supported on activated carbon to produce renewable diesel

    Directory of Open Access Journals (Sweden)

    Nancy Y Acelas

    2017-03-01

    Full Text Available Due to their weak polarity and large surface area, activated carbon supports have the potential to enhance the dispersion of metal-sulfides. It is expected that the absence of a strong metal-support interaction can result in the formation of a very active and stable Ni-Mo-S phase. In this study, catalysts with different amounts of nickel and molybdenum supported on a commercial activated carbon were prepared by a co-impregnation method and characterized by BET, XRF, and SEM techniques. The catalytic activity for hydroprocessing of Jatropha oil was evaluated in a batch reactor, and the composition of the liquid and gaseous products were determined. Results showed that gaseous products are mainly composed of high amounts of propane and small amounts of other light hydrocarbons (C1 to C5. Liquid hydrocarbon products consisted of a mixture containing mainly n-paraffins of C15-C18 and some oxygenated compounds. The catalysts with a mass fraction of 3 % Ni, 15 % Mo (Ni3Mo15/AC presented the highest selectivity toward C17-C18 hydrocarbons, with a product distribution similar to a commercial alumina-supported Ni-Mo-S catalyst.

  6. Electrochemical Deposition and Characterization of Ni-Mo Alloys as Cathode for Alkaline Water Electrolysis

    Science.gov (United States)

    Manazoğlu, Mert; Hapçı, Gökçe; Orhan, Gökhan

    2016-01-01

    In this study, Ni-Mo alloy coatings were electrochemically deposited on a copper plate in citrate solutions. The effects of Ni/Mo mole ratio in the electrolyte and pH value on hydrogen evolution reaction (HER) as well as the electrochemical stability were investigated in the alkaline solution for electrodeposited NiMo. The electrocatalytic activity of the fabricated NiMo alloys for HER in alkaline solutions was investigated by the polarization measurements and electrochemical impedance spectroscopy techniques. The morphology and chemical composition of the electrodeposited Ni-Mo were investigated using SEM and EDS analyses. It was found that NiMo electrode with the highest molybdenum content (ca. 38 wt.%) and high surface area show high electrocatalytic activity in the HER. This was produced from a bath with a pH of 9.5, Ni/Mo ratio of 1/10 and 0.5 M sodium citrate concentration. The stability of this coating was tested by polarization measurements after different anodic and cathodic treatment in 1 M NaOH solution. The open circuit potential ( E ocp) of the electrode as a function of immersion time was also measured.

  7. Electro Deposition of Ni/Ni-MoS2 Self-lubricating Coating on Cemented Carbide%硬质合金表面电沉积Ni/Ni-MoS2自润滑涂层的研究

    Institute of Scientific and Technical Information of China (English)

    曹同坤; 杨岐龙; 单春生

    2012-01-01

    Ni/Ni-MoS2 self-lubricating coatings were prepared on cemented carbide by electro deposition. The effects of current density,pH value,MoS2 concentration of the plating liquid on deposition rate and MoS2 content in coatings were studied. The results indicate that the deposition rate and MoS2 content in coatings are firstly increased and then decreased with the increase of current density, pH value, MoS2 concentration of the plating liquid. The max value of deposition rate, and the max value of MoS2 content in the coatings are reached at the current of 3. 5 A/dm2 and 2 A/dm2 ,separately. The max value of deposition rate and MoS2 content in the coatings are reached at the pH value of 4. 5. The max deposition rate of 0. 812 μm/min ,and the max MoS2 content of 3. 26% are reached when the MoS2 concentration is 28 g/L.%采用电沉积方法在YT14硬质合金表面制备Ni/Ni-MoS2自润滑涂层,研究电流密度、pH值、MoS2加入量对自润滑沉积速率和涂层中MoS2含量的影响.结果表明:随着电流密度、pH值、MoS2加入量的增加,沉积速率和涂层中MoS2的含量都呈现先增加,后下降的规律;电流密度达到3.5 A/dm2时,沉积速率达到最大,电流密度为2 A/dm2时,MoS2的含量最高;在pH值约为4.5时,涂层的沉积速率和涂层中MoS2的含量达到最大值;当MoS2加入量为28g/L时,沉积速率达到最大值为0.812μm/min,涂层中MoS2的质量分数达到最大值为3.26%.

  8. 镍硼及镍钼硼合金镀层的组织和性能研究%Microstructure and Property of Electroless Ni-B and Ni-Mo-B Coatings

    Institute of Scientific and Technical Information of China (English)

    饶群力; 王浩伟; 周尧和

    2001-01-01

    通过化学镀方法制备高硬度Ni-B及Ni-Mo-B合金镀层。经XRD分析确认Ni-B合金镀态镀层组织以非晶态为主,并混有含硼过饱和镍的固溶体。热处理后,Ni-B和Ni-Mo-B两合金镀层的硬度分别高达Hv1200和1400以上。Ni-Mo-B镀层组织及性能随Na2MoO4·2H2O浓度而变化;当浓度为0.604 g/L时,具有最高的硬度。%High hardness Ni-B and Ni-Mo-B coatings are prepared by EN with potassium borohydride reducing agent. As-plating microstructure of Ni-B coating is confirmed to be mixture of amorphous and supersaturated solid solution with XRD analysis. Micro-hardness of Ni-B and Ni-Mo-B coating is more than Hv1200 and 1400 respectively after heat treatment. Property and microstructure of Ni-Mo-B alloy deposit vary with Na2 MoO4 · 2H2O in bath, and optimal one is 0.604g/L.

  9. 电刷镀工艺对 Ni-Mo 合金镀层表面形貌与硬度的影响%Effect of Brush Plating Technology on the Coating Surface Morphology and Microhardness of Ni-Mo Alloys

    Institute of Scientific and Technical Information of China (English)

    徐立鹏; 包春江

    2014-01-01

    Objective To optimize the brush plating technology for the preparation of Ni-Mo alloy coating. Methods Based on orthogonal experiments, Ni-Mo coatings under various conditions were obtained by changing two process parameters, operating volt-age and electrode relative speed. The surface morphology and microhardness of Ni-Mo alloy plating layers were studied using metal-loscope and microhardness tester. Results The optimal parameters of brush plating Ni-Mo alloy were an operating voltage of 14 V and an electrode relative speed of 11. 3 m/ min. The surface of the coating was bright and dense, and the microhardness value was 503. 90HV. Conclusion The research indicated that increasing electrode relative speed or operating voltage could effectively change the deposition rate, surface morphology and microhardness of Ni-Mo alloy coating.%目的:优化电刷镀制备 Ni-Mo 合金镀层工艺,并分析对镀层表面形貌和硬度的影响。方法改变电极相对速度和工作电压,获得不同电刷镀条件下的 Ni-Mo 合金镀层。采用金相显微镜观察镀层的表面形貌,采用显微硬度计测试镀层的显微硬度。结果最佳工艺为:工作电压14 V,电极相对速度11.3 m/ min。镀层光亮致密,显微硬度达到503.90HV。结论适当提高电极相对运动速度、工作电压,能有效改进 Ni-Mo 合金镀层的沉积速度、表面形貌及显微硬度。

  10. Thermodynamic Analysis of Electrodeposited Ni-Mo and Ni-Mo-P Alloys

    Institute of Scientific and Technical Information of China (English)

    GUO Zhong-cheng; XU Rui-dong; WANG Ji-kun

    2004-01-01

    The potential-pH diagram of Ni-P-H2O system is calculated and constructed by use of thermodynamic data. On the basis of the potential-pH diagram the electrochemical behaviors of electrodepositing Ni-Mo and Ni-Mo-P alloys are analyzed. The phases of Ni-Mo and Ni-Mo-P coatings are identified by means of X-ray diffraction analysis. The thermodynamic analysis shows that it is difficult to deposit Mo or P individually from its aqueous solution, and they must be co-deposited with other metals by induced deposition; P and Ni can be deposited as compound Ni3P on the cathode; Mo is deposited in two forms: one is in the form of MoO3 solid particles and the other is in the form of compound MoC. X-ray diffraction analysis is in agreement with the thermodynamic analysis.

  11. Property of AlCrCoFeNiMoTi0.75 Si0.25 High-entropy Alloy Coating Tool Prepared by Laser Cladding%激光熔覆AlCrCoFeNiMoTi0.75Si0.25高熵合金涂层刀具的性能

    Institute of Scientific and Technical Information of China (English)

    张爱荣; 梁红玉; 李烨

    2013-01-01

    利用激光熔覆技术制备了AlCrCoFeNiMoTi0.75Si025高熵合金涂层刀具,研究了激光快速凝固和经过1 000℃退火处理的AlCrCoFeNiMoTi0.75Si0.25高熵合金涂层微观组织和硬度、摩擦磨损性能,并比较了普通高速钢及高熵合金涂层刀具的切削加工性能.结果表明:激光熔覆AlCrCoFeNiMoTi0.5Si0.5高熵合金涂层的主要相结构为bcc相,涂层具有较好的高温稳定性.激光熔覆高熵合金涂层刀具表面硬度高,摩擦因数小,断屑效果好,被加工材料表面光洁度高.%AlCrCoFeNiMoTi0.75Si0.25 high-entropy alloy coated cutting tools was prepared by laser cladding.The microstructure,hardness,friction and wear properties of the AlCrCoFeNiMoTi0.75Si0.25 high-entropy alloy coatings prepared by laser rapid solidification and annealing treatment at 1 000 ℃ were studied.The machinability of the high-speed-steel tools and high-entropy alloy coated tools was compared.Results show that the main alloy structure of the coating is a body centered cubic (BCC) and the coating performs high tempera ture stability.The high-entropy coated cutting tool is characterized by higher hardness,lower friction coefficient,better chip breaker,and better surface finish of the machined materials.

  12. Microstructure and Wear Behavior of FeCoCrNiMo0.2 High Entropy Coatings Prepared by Air Plasma Spray and the High Velocity Oxy-Fuel Spray Processes

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    Tianchen Li

    2017-09-01

    Full Text Available In the present research, the spherical FeCoCrNiMo0.2 high entropy alloy (HEA powders with a single FCC solid solution structure were prepared by gas atomization. Subsequently, the FeCoCrNiMo0.2 coatings with a different content of oxide inclusions were prepared by air plasma spraying (APS and high-velocity oxy-fuel spraying (HVOF, respectively. The microstructure, phase composition, mechanical properties, and tribological behaviors of these HEA coatings were investigated. The results showed that both HEA coatings showed a typical lamellar structure with low porosity. Besides the primary FCC phase, a mixture of Fe2O3, Fe3O4, and AB2O4 (A = Fe, Co, Ni, and B = Fe, Cr was identified as the oxide inclusions. The oxide content of the APS coating and HVOF coating was calculated to be 47.0% and 12.7%, respectively. The wear resistance of the APS coating was approximately one order of magnitude higher than that of the HVOF coating. It was mainly attributed to the self-lubricated effect caused by the oxide films. The mass loss of the APS coating was mainly ascribed to the breakaway of the oxide film, while the main wear mechanism of the HVOF coating was the abrasive wear.

  13. Ni/Mo2C nanowires and their carbon-coated composites as efficient catalysts for nitroarenes hydrogenation

    Science.gov (United States)

    Shu, Yijin; He, Sina; Xie, Lifang; Chan, Hang Cheong; Yu, Xiang; Yang, Lichun; Gao, Qingsheng

    2017-02-01

    The hydrogenation of nitroarenes to value-added aromatic amines requires active and selective catalysts. Due to the good efficiency, economic cost and high earth-abundance, Ni-based nanostructures emerge as the promising catalysts, which are however limited by the poor dispersion and unsatisfied durability. Herein, Mo2C nanowires was introduced as a versatile support towards the highly dispersive Ni owing to the strong metal-support interactions on carbide surface, accomplishing the high activity in the hydrogenation of 3-nitrobenzoic acid, 4-nitrobenzoic acid and nitrobenzene. However, the presence of water that promoted the selective hydrogenation unfortunately deactivated Ni species. An effective carbon coating was further introduced to remarkably enhance the stability, protecting active Ni from corrosive H+ and H2O. This work elucidates a feasible way towards efficient and stable catalysts by the introduction of both carbide supports and carbon coating, shedding some light on the development of high-performance catalysts.

  14. Surface morphology and electrochemical characterization of electrodeposited Ni-Mo nanocomposites as cathodes for hydrogen evolution

    Science.gov (United States)

    Elhachmi Guettaf, Temam; Hachemi Ben, Temam; Said, Benramache

    2015-10-01

    In this work, we study the influences of current density on surface morphology and electrochemical characterization of electrodeposited Ni-Mo. The Ni-Mo composite coatings are deposited on pretreated copper substrates by electrolytic deposition. The Ni-Mo solution is taken from nickel sulfate fluid and ammonium heptamolybdate with 10 g/l. The Ni-Mo composite coatings are deposited at a temperature of 303 K with an applied current density of jdep = 10 A/dm2-30 A/dm2. We find that the corrosion resistance is improved by incorporating Mo particles into Ni matrix in 0.6-M NaCl solution. From the potentiodynamic polarization curve of electrodeposited Ni-Mo it is confirmed that the corrosion resistance decreases with increasing applied current density. The x-ray diffraction (XRD) analyses of Ni-Mo coatings indicate three phases of MoNi4, Mo1.24Ni0.76, and Ni3Mo phases crystallites of nickel and molybdenum. The scanning electronic microscopy (SEM) tests indicate that Ni-Mo coatings present cracks and pores.

  15. Ni-Mo-Co ternary alloy as a replacement for hard chrome

    Science.gov (United States)

    Srivastava, Meenu; Anandan, C.; Grips, V. K. William

    2013-11-01

    Hard chrome is the most extensively used electroplated coating in the aerospace and automotive industries due to its attractive properties such as high hardness and excellent wear resistance. However, due to the health risks associated with the use of hexavalent chromium baths during electroplating, there is a need to identify an alternative to this coating. In this study a nickel-molybdenum alloy with cobalt as the alloying element has been developed. The coating was characterized for its micro hardness, wear resistance, coefficient of friction and corrosion resistance. The coating was also subjected to heat treatment at temperatures in the range of 200°-600 °C. It was observed that the micro hardness of Ni-Mo-Co (730 KHN) alloy coating under optimized conditions is apparently quiet similar to that of the most probable substitute Co-P (745 VHN) and hard chrome (800 VHN) coatings. The tribological properties like the wear rate and coefficient of friction of the 400 °C heat treated Ni-Mo-Co coating were noticed to be better compared to hard chrome coating. The electrochemical impedance and polarization studies showed that the corrosion resistance of heat treated Ni-Mo-Co alloy was better than as-deposited Ni-Mo-Co and Ni-Mo coating.

  16. ACTIVITY TEST AND REGENERATION OF NiMo/Z CATALYST FOR HYDROCRACKING OF WASTE PLASTIC FRACTION TO GASOLINE FRACTION

    Directory of Open Access Journals (Sweden)

    Rodiansono Rodiansono

    2010-06-01

    Full Text Available Activity test and regeneration of NiMo/active natural zeolite catalyst for hydrocracking of waste plastic fraction of polyprophylene (PP type have been carried out. The catalysts was prepared by loading Mo followed by Ni Metals onto the natural zeolite (Z sample, then calcined at 500oC, oxidized and reduced at 400oC under nitrogen, oxygen and hydrogen stream, respectively. The characterization of catalysts including spesific surface area, average pore radius, and total pore volume were performed by gas sorption analyzer, amount of total acid sites was determined by gas sorption method, and acid site strength was confirmed by IR spectroscopy. The hydrocracking process was carried out in a semi-flow reactor system at 360 oC and catalyst:feed ratio 0.5 under hydrogen stream (150 mL/hour. The feed was vaporized from the pyrolisis reactor into the hydrocracking reactor. A liquid product was collected and analyzed by gas chromatography (GC and gas chromatography-mass spectroscopy (GC-MS. The characterization results showed that spesific surface area, average pore radius, and total pore volume of the Z sample decreased after loading of the Ni and Mo metals. Amount of total acid sites of the NiMo/Z catalyst was higher than that of the Z sample. The activity of NiMo/Z catalyst decreased after several continously runs. Its regeneration produced the NiMo/Z reg catalyst with similar activity and selectivity to the fresh catalyst (NiMo/Z. The activity of catalysts at the optimum condition followed the order of NiMo/Z reg>NiMo/Z>Z (conversion of hydrocarbon C>12 and NiMo/Z reg>NiMo/Z>Z (total yield of gasoline fraction. The selectivity of catalysts for C7-C8 product followed the order of Z>NiMo/Z>NiMo/Z reg. Keywords: activity, polyprophylene, catalyst, gasoline fraction.

  17. Electrochemical deposition and characterization of Ni-Mo alloy powders

    Directory of Open Access Journals (Sweden)

    M.G. Pavlović

    2007-12-01

    Full Text Available Electrodeposition of Ni-Mo alloy powders from ammonium sulfate and ammonium chloride containing electrolytes of different Ni/Mo ions concentration ratios was investigated by polarization measurements. The morphology, chemical composition and phase composition of electrodeposited Ni-Mo alloy powders were investigated using DSC, TGA, SEM, EDS and XRD analysis. EDS results showed that powder composition depends on Ni/Mo ions concentration ratio, as well as on the position where the EDS analysis was performed. As-deposited alloy powders were nanocrystalline showing no XRD peaks with undefined morphology (SEM. After recrystallization for 2 h in N2 atmosphere at 600°C the presence of NiMoO4 phase was identified in the powder electrodeposited from chloride electrolyte at the Ni/Mo ions concentration ratio 1/3, with well defined crystalline powder particles.

  18. Preparation of ZnNiMo/{gamma}-alumina catalysts from recycled Ni for hydrotreating reactions

    Energy Technology Data Exchange (ETDEWEB)

    Linares, Carlos F.; Lopez, Julio [Laboratorio de Catalisis y Metales de Transicion, Facultad de Ciencias y Tecnologia, Departamento de Quimica, Universidad de Carabobo, Valencia Edo Carabobo, Apartado Postal 3336 (Venezuela); Scaffidi, Adriana; Scott, Carlos E. [Centro de Catalisis, Petroleo y Petroquimica, Universidad Central de Venezuela, Facultad de Ciencias, Apartado 47102, Los Chaguaramos, Caracas (Venezuela)

    2005-09-18

    Ni, recovered from Ni-Cd cellular phone batteries, was used in the preparation of ZnNiMo/Al{sub 2}O{sub 3} catalysts. The catalysts were characterized by temperature programmed reductions (TPR), surface area determinations (BET) and chemical analysis. Vanadyl octaethyl porphyrin (VOOEP) hydrodeporphyrinization (HDP) and thiophene hydrodesulfurization (HDS) were used as catalytic tests. It was found that the addition of Zn increases the ratio between octahedral and tetrahedral Mo in ZnMo and ZnNiMo catalysts, and that Ni addition lowers the reduction temperature of Mo species. Both results induce a positive synergetic effect for HDP and HDS reactions. An activity maximum was found for the catalyst with a Zn/(Zn+Ni) atomic ratio equal to 0.29, for both reactions. Finally, the use of a possible pollutant (Ni-Cd batteries) to produce a catalyst to eliminate contaminants in fuels was shown to be feasible.

  19. Nanocrystalline NiMoO4 with an ordered mesoporous morphology as potential material for rechargeable thin film lithium batteries.

    Science.gov (United States)

    Haetge, Jan; Djerdj, Igor; Brezesinski, Torsten

    2012-07-07

    Nanocrystalline nickel molybdate (NiMoO(4)) thin film electrodes with a 3D honeycomb structure of uniform 17 nm diameter pores were successfully produced through facile polymer templating strategies. These novel sol-gel type materials exhibit enhanced lithium ion storage capabilities, and thus show promise for battery applications.

  20. A one-dimensional porous carbon-supported Ni/Mo2C dual catalyst for efficient water splitting.

    Science.gov (United States)

    Yu, Zi-You; Duan, Yu; Gao, Min-Rui; Lang, Chao-Chao; Zheng, Ya-Rong; Yu, Shu-Hong

    2017-02-01

    The development of active, stable and low-cost electrocatalysts towards both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) for overall water splitting remains a big challenge. Herein, we report a new porous carbon-supported Ni/Mo2C (Ni/Mo2C-PC) composite catalyst derived by thermal treatment of nickel molybdate nanorods coated with polydopamine, which efficiently and robustly catalyses the HER and OER with striking kinetic metrics in alkaline electrolyte. The catalyst affords low onset potentials of -60 mV for the HER and 270 mV for the OER, as well as small overpotentials of 179 mV for the HER and 368 mV for the OER at a current density of 10 mA cm(-2). These results compare favorably to Mo2C-PC, Ni-PC, and most other documented Ni- and Mo-based catalysts. The high activity of Ni/Mo2C-PC is likely due to electron transfer from Ni to Mo2C, leading to a higher Ni valence and a lower Mo valence in the Ni/Mo2C-PC catalyst, as these are HER and OER active species and thus account for the enhanced activity. Remarkably, our home-made alkaline electrolyser, assembled with Ni/Mo2C-PC as a bifunctional catalyst, can enable a water-splitting current density of 10 mA cm(-2) to be achieved at a low cell voltage of 1.66 V.

  1. OPTIMASI TEMPERATUR HIDRODESULFURISASI TIOFEN TERKATALISIS NI-MO/ZEOLIT ALAM

    Directory of Open Access Journals (Sweden)

    Harjito -

    2013-07-01

    Full Text Available Telah dilakukan kajian mengenai pengaruh temperatur hidrodesulfurisasi terhadap produk hidrodesulfurisasi tiofen. Penelitian dilakukan untuk mengetahui temperatur optimum hidrodesulfurisasi tiofen dengan katalis Ni-Mo/zeolite alam. Variasi temperatur yang dilakukan adalah 3000C, 3500Cdan 4000C. Katalis Ni-Mo/Zeolit alam dipreparasi secara koimpregnasi. Proses hidrodesulfurisasi dilakukan dengan umpan campuran tiofen-n-heksan dengan komposisi 1:1. Sebagai gas pembawa digunakan gas hydrogen dengan laju alir 25 mL/menit. Hasil hidrodesulfurisasi didinginkan dan dianalisis dengan kromatografi gas. Hasil analisis menunjukkan terjadinya peningkatan jumlah produk dan komponen produk pada setiap kenaikan temperatur 500C. Namun demikian kenaikan jumlah produk pada kenaikan temperatur dari 3500C ke 4000C jika dibandingkan dengan kenaikan produk pada kenaikan temperatur dari 3000C ke 3500C tidak cukup signifikan. Jadi dapat disimpulkan bahwa temperatur hidrodesulfurisasi tiofen terkatalisis Ni-Mo/Zeolit alam adalah 3500C. The study on the effect of temperature on the product tiofen hydrodesulfurization by using Ni/Mo/natural tiofen-n-hexane. The study was done conducted to determine the optimum temperature of  hydrodesulfurization tiofen by using Ni-Mo/ natural zeolite catalyst and the temperature variation was 300oC, 350oC dan 400oC. The Ni-Mo/ natural Zeolit  catalysts were prepared by coimpregnation and hydrodesulfurization process was done by tiofen-n-hexane feed mixture with composition of 1:1, hydrogen gas was used as a carrier gas with a flow rate 25 ml/min. The result of  hydrodesulfurization was cooled and analyzed by gas chromatography  and it revealed an increasing number of products and product components at for each 50°C rising of temperature. However, the increasing of number of products on the temperature rise of  350°C to 400°C was not significant if compared to the increasing of product temperature that increased

  2. Process and apparatus for producing coated particles

    NARCIS (Netherlands)

    Van Ommen, J.R.; Ellis, N.; Yurteri, C.; Marijnissen, J.C.M.

    2010-01-01

    The invention is directed to a process and apparatus for preparing coated particles, in particular a process for preparing particles that are coated with small particles using electrospraying. The coated particles produced according to the present invention find use for instance as catalysts or as

  3. Kinetics of Ni-Mo electrodeposition from Ni-rich citrate baths

    Energy Technology Data Exchange (ETDEWEB)

    Beltowska-Lehman, E., E-mail: nmbeltow@imim-pan.krakow.pl; Indyka, P.

    2012-01-01

    The kinetics of Ni-Mo alloy electrodeposition on steel substrates from an aqueous citrate-ammonia complex baths has been investigated by means of steady-state polarisation measurements in a system with a rotating disc electrode (RDE). Partial current densities for discharge of Ni(II) and Mo(VI) ions and hydrogen evolution as a function of molybdate concentration in the bath, cathode potentials and the rate of mass transport were determined. It has been shown that - under all investigated conditions - Ni-Mo alloy deposition is more favourable than pure nickel and the cathodic process is strongly influenced by the Mo(VI) content in the solution. The Ni(II) electroreduction rate initially increases, as the cathode potential shifts towards more negative values and the concentration of molybdate grows in the solution. However, for the highest examined MoO{sub 4}{sup 2-} content, a considerable decrease in the rate of the process is subsequently observed at certain limit potentials, the values of which depend on molybdate concentration and hydrodynamic conditions. This effect, related to the formation of intermediate molybdenum oxides (characterised by very low overvoltage for hydrogen evolution), becomes less pronounced when the RDE rotation speed is increased. Hydrogen evolution is strongly associated with molybdenum deposition. An increase of the molybdate ions concentration in the bath, as well as an increase in the rate of mass transport, leads to an increase in Mo content in deposits and to the reduction of current efficiency. The Ni-Mo coatings electrodeposited from the designed bath (with the current efficiency of about 70%) containing about 30 wt.% Mo, are characterised by a shiny-grey appearance and good adhesion to the steel substrate. They are characterised by column growth and amorphous microstructure with randomly distributed nanocrystallites of the MoNi{sub 4} intermetallic phase.

  4. Microstructure Characterization and Wear-Resistant Properties Evaluation of an Intermetallic Composite in Ni-Mo-Si System.

    Science.gov (United States)

    Huang, Boyuan; Song, Chunyan; Liu, Yang; Gui, Yongliang

    2017-02-04

    Intermetallic compounds have been studied for their potential application as structural wear materials or coatings on engineering steels. In the present work, a newly designed intermetallic composite in a Ni-Mo-Si system was fabricated by arc-melting process with commercially pure metal powders as starting materials. The chemical composition of this intermetallic composite is 45Ni-40Mo-15Si (at %), selected according to the ternary alloy diagram. The microstructure was characterized using optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive spectroscopy (EDS), and the wear-resistant properties at room temperature were evaluated under different wear test conditions. Microstructure characterization showed that the composite has a dense and uniform microstructure. XRD results showed that the intermetallic composite is constituted by a binary intermetallic compound NiMo and a ternary Mo₂Ni₃Si metal silicide phase. Wear test results indicated that the intermetallic composite has an excellent wear-resistance at room-temperature, which is attributed to the high hardness and strong atomic bonding of constituent phases NiMo and Mo₂Ni₃Si.

  5. Synthesis and characterization of Ni-Mo filler brazing alloy for Mo-W joining for microwave tube technology

    Directory of Open Access Journals (Sweden)

    Frank Ferrer Sene

    2013-04-01

    Full Text Available A brazing process based on Ni-Mo alloy was developed to join porous tungsten cathode bottom and dense molybdenum cathode body for microwave tubes manufacture. The Ni-Mo alloy was obtained by mixing and milling powders in the eutectic composition, and applied on the surface of the components. The brazing was made at 1400 °C by using induction heating in hydrogen for 5 minutes. Alumina surfaces were coated with the binder and analyzed by Energy Dispersive X-rays Fluorescence. The brazed samples were analyzed by Scanning Electron Microscopy coupled to Energy Dispersive Spectroscopy. Stress-strain tests were performed to determine the mechanical behavior of the joining. The quality of the brazing was evaluated by assuring the presence of a "meniscus" formed by the Ni-Mo alloy on the border of the tungsten and molybdenum joint, the absence of microstructural defects in the interface between the tungsten and molybdenum alloys, and the adhesion of the brazed components.

  6. Sinter-hardening of Ni-Mo pre-alloyed powders with tungsten addition

    Directory of Open Access Journals (Sweden)

    L.A. Dobrzański

    2007-01-01

    Full Text Available Purpose: Purpose of this paper was to present the benefits of powder metallurgy technology and development ofsinter-hardening process. The mechanical properties, focusing in particular on hardness and wear resistance, oftwo different carbon levels pre-alloyed steel powders processed with sinter-hardening method, were described.Microstructure characteristic of produced sinter-hardened Ni-Mo steels with increasing amount of tungsten(from 0 to 0.3% wt. was taken under consideration.Design/methodology/approach: Different compositions have been tested in order to investigate the influenceof various tungsten additions into low (0.4% and high (0.6% carbon content of pre-alloyed steel powders.Powders, with addition of 0.7% lubricant, were pressed in a 2000kN hydraulic press. De-waxing process at550ºC for 60 minutes in a fully nitrogen atmosphere was performed before the sintering. Sintering was carriedout in vacuum furnace with argon backfilling. The furnace was equipped with a cooling zone to provideaccelerated cooling from the sintering temperature. Green compacts were sintered at the temperature 1120ºC for1 hour and rapidly cooled with a rate 2.5ºC/s.Findings: The applied sinter-hardening process resulted with achievement of material characterized by goodwear resistance. The investigation of Ni-Mo and Ni-Mo-W sinter-hardened steels with low and high carboncontent proved that applied process of sintering under vacuum and rapid cooling brought expected outcome.Research limitations/implications: Considering the achieved outcome, it was revealed that chemical compositionand applied process of steels preparation, sinter-hardening with the cooling rate 2.5ºC/s, results in achieving materialswith relatively high hardness and significant resistance to abrasion. Anyhow, further research should be performed.Originality/value: Sinter-hardening of Ni-Mo pre-alloyed powders with the addition of different additions oftungsten, especially in terms of

  7. Synthesis,characterization and hydrodesulfurization activity of silica-dispersed NiMoW trimetallic catalysts

    Institute of Scientific and Technical Information of China (English)

    Di Liu; Lihua Liu; Guangci Li; Chenguang Liu

    2010-01-01

    Silica-dispersed NiMoW trimetallic hydrodesulfurization catalysts were prepared by deposition-precipitation method.For comparative purposes,bulk NiMoW trimetallic catalysts were obtained by co-precipitation.Silica was employed to disperse active metals for full utilization of active components and silica-dispersed NiMoW catalyst had high active metal content.BET analysis showed that silica-dispersed NiMoW trimetallic catalysts had a high surface area(165.1 m2/g)and pore volume(0.27 ml/g).Transmission electron microscopy results proved that active components were well dispersed.Hydrodesulfurization activity of silica-dispersed NiMoW catalysts was much higher than that of comparative catalysts and up to twice greater than those of commercial NiMo alumina-supported systems per gram of catalyst.

  8. Hydrocracking of Jatropha Oil over non-sulfided PTA-NiMo/ZSM-5 Catalyst

    Science.gov (United States)

    Yang, Xiaosong; Liu, Jing; Fan, Kai; Rong, Long

    2017-01-01

    The PTA-NiMo/ZSM-5 catalyst impregnated with phosphotungstic acid (PTA) was designed for the transformation of Jatropha oil into benzene, toluene, and xylenes (BTX) aromatics. The produced catalyst was characterized by N2 adsorption-desorption, powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), and the temperature-programmed desorption of ammonia (NH3-TPD). The catalytic performance was evaluated by gas chromatography (GC). The liquid products were 70 wt% of the feed oil, and the majority of the liquid products were BTX. The aromatization activity of the catalyst was improved by the addition of PTA and the hierarchical process. The favorable PTA amount was 20 wt% and the yield of BTX was 59 wt% at 380 °C, 3 MPa, H2/oil (v/v) = 1000 and LHSV = 1 h-1 over the PTA20-NiMo/HZ0.5 catalyst (PTA 20 wt%) without sulfurization.

  9. Investigation of the Hydroisomerization Activities of Ni-Mo Catalysts Loaded on HY and HUSY Zeolites

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A series of Ni-Mo/zeolite-A12O3 catalysts was prepared by incipient wetness impregnation andtheir catalytic experiments were carried out using an automated microflow apparatus. It is concluded that theNi-Mo catalyst loaded on the HUSY has larger BET surface areas and possesses more acid sites than thatloaded on the HY zeolite, and simultaneously the Ni-Mo/HUSY-A12O3 catalyst reveals higher catalytic activ-ity characterized by feedstock conversion and isomer yield which is about two or three times higher than thatof the Ni-Mo/HY-A12O3 catalyst.

  10. Enhanced field emission performance of NiMoO4 nanosheets by tuning the phase

    Science.gov (United States)

    Bankar, Prashant K.; Ratha, Satyajit; More, Mahendra A.; Late, Dattatray J.; Rout, Chandra Sekhar

    2017-10-01

    In this paper we report, large scale synthesis of α and β-NiMoO4 by a facile hydrothermal method and we observed that urea plays important role on the growth of β-NiMoO4 nanosheets. We have also carried out field emission (FE) investigations of α and β-NiMoO4 at a base pressure of ∼1 × 10-8 mbar. The obtained turn-on field at emission current density of 1 μA/cm2 for β-NiMoO4 nanosheets and α -NiMoO4 is 1.3 V/μm and 2.2 V/μm respectively were observed. The maximum field emission current density of 1.006 mA/cm2at an applied electric field of 2.7 V/μm was achieved for β-NiMoO4 nanosheets. Furthermore, we found that the β-NiMoO4 nanosheets possess good field emission performance compared to α-NiMoO4. The results indicate that NiMoO4can be used as a promising material in FE applications with possibility of tuning field emission performance by controlling the phase.

  11. The Effect of Milling Time on the Microstructural Characteristics and Strengthening Mechanisms of NiMo-SiC Alloys Prepared via Powder Metallurgy

    Directory of Open Access Journals (Sweden)

    Chao Yang

    2017-04-01

    Full Text Available A new generation of alloys, which rely on a combination of various strengthening mechanisms, has been developed for application in molten salt nuclear reactors. In the current study, a battery of dispersion and precipitation-strengthened (DPS NiMo-based alloys containing varying amounts of SiC (0.5–2.5 wt % were prepared from Ni-Mo-SiC powder mixture via a mechanical alloying (MA route followed by spark plasma sintering (SPS and rapid cooling. Neutron Powder Diffraction (NPD, Electron Back Scattering Diffraction (EBSD, and Transmission Electron Microscopy (TEM were employed in the characterization of the microstructural properties of these in-house prepared NiMo-SiC DPS alloys. The study showed that uniformly-dispersed SiC particles provide dispersion strengthening, the precipitation of nano-scale Ni3Si particles provides precipitation strengthening, and the solid-solution of Mo in the Ni matrix provides solid-solution strengthening. It was further shown that the milling time has significant effects on the microstructural characteristics of these alloys. Increased milling time seems to limit the grain growth of the NiMo matrix by producing well-dispersed Mo2C particles during sintering. The amount of grain boundaries greatly increases the Hall–Petch strengthening, resulting in significantly higher strength in the case of 48-h-milled NiMo-SiC DPS alloys compared with the 8-h-milled alloys. However, it was also shown that the total elongation is considerably reduced in the 48-h-milled NiMo-SiC DPS alloy due to high porosity. The porosity is a result of cold welding of the powder mixture during the extended milling process.

  12. Study of NiMo/ZrO2 Catalysts for Hydrodesulfurization%NiMo/ZrO2加氢脱硫催化剂的研究

    Institute of Scientific and Technical Information of China (English)

    贾美林; P Afanasiev; M Vrinat; 李文钊; 徐恒泳; 葛庆杰

    2005-01-01

    采用共浸法制备了未经焙烧直接硫化的NiMo/ZrO2(550)、NiMo/ZrO2(650)催化剂及550℃焙烧后再硫化的NiMo/ZrO2(550)-1催化剂,在连续流动微反装置上考察了NiMo/ZrO2系列催化剂对噻吩加氢脱硫反应的催化活性,并对催化剂进行了X射线光电子能谱(XPS)和Raman光谱表征.表征结果显示,以四方相ZrO2为载体的NiMo/ZrO2(650)催化剂,由于被硫化的更完全,催化活性高于以无定形相ZrO2为载体的NiMo/ZrO2(550)催化剂,说明载体的结构影响催化剂的催化活性;550℃焙烧后的NiMo/ZrO2(550)-1催化剂的催化活性低于未经焙烧直接硫化的NiMo/ZrO2(550)催化剂,这是由于高温焙烧增加了活性组分和载体之间的相互作用,降低了催化剂的硫化程度,进而降低了其催化活性,说明这种强相互作用不利于提高催化剂的催化活性.

  13. Density of Liquid Ni-Mo Alloys Measured by a Modified Sessile Drop Method

    Institute of Scientific and Technical Information of China (English)

    Liang FANG; Zushu LI; ZaiNan TAO; Feng XIAO

    2004-01-01

    The density of liquid binary Ni-Mo alloys with molybdenum concentration from 0 to 20% (mass fraction) was measured by a modified sessile drop method. It has been found that the density of the liquid Ni-Mo alloys decreases with increasing temperature, but increases with the increase of molybdenum concentration in the alloys. The molar volume of liquid Ni-Mo binary alloys increases with the increase of temperature and molybdenum concentration. The partial molar volume of molybdenum in Ni-Mo binary alloy has been approximately calculated as [13.18 - 2.65 × 10-3T + (-47.94 + 3.10 × 10-2T) × 10-2XMo] × 10-6m3·mol-1. The molar volume of Ni-Mo alloy determined in the present work shows a negative deviation from the ideal linear mixing molar volume.

  14. A one-dimensional porous carbon-supported Ni/Mo2C dual catalyst for efficient water splitting? ?Electronic supplementary information (ESI) available: Experimental details, XRD patterns, SEM and TEM images, BET and Raman data, and electrochemical tests. See DOI: 10.1039/c6sc03356c Click here for additional data file.

    OpenAIRE

    Yu, Zi-You; Duan, Yu; Gao, Min-Rui; Lang, Chao-Chao; Zheng, Ya-Rong; Yu, Shu-Hong

    2016-01-01

    The development of active, stable and low-cost electrocatalysts towards both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) for overall water splitting remains a big challenge. Herein, we report a new porous carbon-supported Ni/Mo2C (Ni/Mo2C-PC) composite catalyst derived by thermal treatment of nickel molybdate nanorods coated with polydopamine, which efficiently and robustly catalyses the HER and OER with striking kinetic metrics in alkaline electrolyte. The catal...

  15. Reactivity and Morphology of Ni, Mo, and Ni-Mo Oxide Clusters Supported on MCM-48 Toward Thiophene Hydrodesulphurization

    Science.gov (United States)

    Bartholomew, Catherine; Chakradhar, Ashish; Burghaus, Uwe; Wu, Chia-Ming; Peng, Rui; Mishra, Srujan; Koodali, Ranjit T.

    2014-07-01

    In this paper, the morphology, chemical composition and reactivity of MCM-48 powders impregnated with Ni, Mo or both toward hydrodesulphurization (HDS) of thiophene were characterized. The reactivity of the catalyst was quantitatively compared with a standard industrial catalyst (from HaldorTopsoe, Denmark) and a novel WS2 nanotube-based catalysts (from R. Tenne, Israel). Morphology and chemical composition were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), and EDX elemental maps. Reactivity was determined in a gas-chromatograph based mini flow reactor using thiophene as a probe molecule. The sulfided MCM-48 supported Mo catalyst showed the largest HDS activity with turnover frequencies (TOF) about half as large as for the commercial system under the test conditions used here. Presulfiding did increase activity of all MCM-48 catalysts.

  16. Self-Assembly of Hierarchical Ni-Mo-Polydopamine Microflowers and their Conversion to a Ni-Mo2 C/C Composite for Water Splitting.

    Science.gov (United States)

    Sun, Lianshan; Wang, Chunli; Sun, Qujiang; Cheng, Yong; Wang, Limin

    2017-04-03

    With the aim of finding efficient non-noble metal catalysts for water splitting, hierarchical Ni-Mo-polydopamine microflowers (Ni-Mo2 C/C MF) were synthesized through a facile aqueous-phase reaction at room temperature. NiMoO4 nanowires were utilized as both Ni and Mo source; they can complex with dopamine to form a hierarchical structure and affect the scale of the final product. The energy dispersive spectroscopy (EDS) measurement of Ni-Mo2 C/C microflowers (MF) shows a high content of Mo2 C and Ni (>90 wt %). For the hydrogen evolution reaction (HER), the Ni-Mo2 C/C MF displays a low overpotential of 99 mV at a current density of -10 mA cm(-2) and a small Tafel slope of 73 mV dec(-1) in 1.0 m KOH. By comparison with Mo2 C/C microspheres (MS), the nanosized Ni-doped particles offer more active sites and enhance the kinetic performance. This facile synthesis strategy is also suitable for preparing other metal-Mo2 C/C composites that can be used in the fields of catalysis and energy conversion. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Deep Hydrodesulfurization of Diesel Fuel over Diatomite-dispersed NiMoW Sulifde Catalyst

    Institute of Scientific and Technical Information of China (English)

    Liu Di; Liu Chenguang

    2013-01-01

    Diatomite-dispersed NiMoW catalyst was prepared and characterized,and the activity of catalyst samples was tested during the HDS reaction of FCC diesel. Sulfur compounds in the feedstock and the hydrogenated products obtained over different catalysts were determined by GC-PFPD. The test results showed that the diatomite-dispersed NiMoW catalyst had high hydrodesulfurization activity for FCC diesel, which could be contributed to the excellent hydrogenation perfor-mance of the said catalyst. Characterization of catalyst by TEM and XRD indicated that the diatomite-dispersed NiMoW catalyst possessed higher layer stacking, larger curvature of MoS2 or WS2, and segregated Ni3S2 crystals relative to the sup-ported catalyst. This kind of structure leads to high hydrogenation activity of the diatomite-dispersed NiMoW catalyst.

  18. Crystallisation of partially amorphized Ni-Mo alloy

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Sanchez, R.; Diaz de la Torre, S.; Espinosa-Magana, F. [Centro de Investigacion en Materiales Avanzados (CIMAV), Chihuahua (Mexico); Bejar Gomez, L. [Centro de Investigacion en Materiales Avanzados (CIMAV), Chihuahua (Mexico); Univ. Michoacana de San Nicolas de Hidalgo, Morelia (Mexico); Cabanas-Moreno, J.G. [Inst. Politecnico Nacional, ESFM, UPALM-Zacatenco, Mexico D.F. (Mexico)

    2001-07-01

    The Ni-Mo system processed through mechanical alloying (MA) technique has been widely investigated. Complete or partial amorphisation in this binary system mainly depends on the concentration of the elements. A new microstructural phase, called ''Y'' has been reported upon crystallisation of the powder. Although the ''Y'' phase formation has been attributed to the presence of C, O or N contaminants, its identification and characteristics remains unclear. In this work, an oxicarbide (Ni{sub 6}Mo{sub 6}(C,O){sub 1.06}) has been identified in samples in the as-heated condition and has been found as the crystallised phase in major amount in the final product. The XRD pattern of this oxicarbide is very similar to that reported before for a new phase called ''Y''. The simulated XRD pattern of oxicarbide (Ni{sub 6}Mo{sub 6}(C,O){sub 1.06}) is in good agreement with that experimentally found in this work. The activation energy required to induce crystallisation ({proportional_to}336 kJ/mol) matches well to the values reported in literature. (orig.)

  19. Cracking vegetable oil from Callophylluminnophyllum L. seeds to bio-gasoline by Ni-Mo/Al2O3 and Ni-Mo/Zeolite as micro-porous catalysts

    Science.gov (United States)

    Savitri, Effendi, R.; Tursiloadi, S.

    2016-02-01

    Natural minerals such as zeolite are local natural resources in the various regions in Indonesia. Studies on the application of natural mineral currently carried out by national research institutions, among others, as a filler, bleaching agent, or dehydration agent. However, not many studies that utilize these natural minerals as green catalysts material which has high performance for biomass conversion processes and ready to be applied directly by the bio-fuel industry. The trend movement of green and sustainable chemistry research that designing environmentally friendly chemical processes from renewable raw materials to produce innovative products derived biomass for bio-fuel. Callophylluminnophyllum L. seeds can be used as raw material for bio-energy because of its high oil content. Fatty acid and triglyceride compounds from this oil can be cracked into bio-gasoline, which does not contain oxygen in the hydrocarbon structure. Bio-gasoline commonly is referred to as drop-in biofuel because it can be directly used as a substitute fuel. This paper focused on the preparation and formulation of the catalyst NiMo/H-Zeolite and Ni-Mo/Al2O3 which were used in hydro-cracking process of oil from Callophylluminnophyllum L. seeds to produce bio-gasoline. The catalysts were analyzed using XRD, BET and IR-adsorbed pyridine method. The results of hydro-cracking products mostly were paraffin (C10-C19) straight chain, with 59.5 % peak area based on GC-MS analysis.

  20. Mechanism of Cracking Resistance of Hardfacing Specimens of Steel 5CrNiMo Improved by Rare Earth Oxide

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The cracking morphology of the hardfacing specimens taken from steel 5CrNiMo was observed. Meanwhile, the residual stress fields were measured and simulated. Based on experiment mentioned above, the improved structure and modified inclusion in hardfacing metal with rare earth (RE) oxide were analyzed. The results show that, the hardfacing crack is initiated from the coarse dendritic crystal grain boundary, inclusions and coarse austenite grain boundary in the HAZ and propagated by the residual stress existing in the center of the hardfacing metal and HAZ. The primary columnar grain structure can be refined by adding RE oxide in the coating of the electrode. The inclusion in the hardfacing metal can be modified as well. Meanwhile, if the martensite transformation temperature is decreased, the largest value of the residual tensile stress in the dangerous region can be reduced.

  1. Electrochemical behavior of Ni-Mo electro catalyst for water electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez V, S. M.; Ordonez R, E. [ININ, Departamento de Quimica, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Cabanas M, G. [IPN, Centro de Nanociencias y Micro y Nanotecnologias, A. P. 75-874, 07300 Mexico D. F. (Mexico); Solorza F, O., E-mail: suilma.fernandez@inin.gob.m [IPN, Centro de Investigacion y de Estudios Avanzados, Departamento de Quimica, A. P. 14-740, 07000 Mexico D. F. (Mexico)

    2010-07-01

    Nickel-molybdenum based electrocatalysts were synthesized in organic media for the hydrogen evolution reaction and oxygen evolution reaction in alkaline media. The structure, morphology and chemical composition of the catalysts were evaluated by X-ray diffraction, scanning electron microscopy and Aas. Results revealed nanocrystalline powder materials with Ni{sub 0.006}Mo, Ni{sub 0.1}Mo and Ni Mo compositions. The best performance for hydrogen evolution reaction, was obtained on Ni{sub 0.1}Mo electrode, whereas Ni Mo was for the oxygen evolution reaction. Results suggest that the material with 1:1 stoichiometric ratio could be considered as a promising electro catalyst for oxygen evolution reaction. This nanocrystalline powder is formed by Ni{sub 2}Mo{sub 3}O{sub 8} and a crystalline structure attributed to the possible formation of a Ni Mo cluster, becomes NiMoO{sub 4} after thermal treatment at 1073 K in air. The Ni Mo 1:1 cluster catalyst presented electrochemical stability during the oxygen evolution reaction. (Author)

  2. Method to produce catalytically active nanocomposite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Erdemir, Ali; Eryilmaz, Osman Levent; Urgen, Mustafa; Kazmanli, Kursat

    2016-02-09

    A nanocomposite coating and method of making and using the coating. The nanocomposite coating is disposed on a base material, such as a metal or ceramic; and the nanocomposite consists essentially of a matrix of an alloy selected from the group of Cu, Ni, Pd, Pt and Re which are catalytically active for cracking of carbon bonds in oils and greases and a grain structure selected from the group of borides, carbides and nitrides.

  3. Producing Functionally Graded Coatings by Laser-Powder Cladding

    NARCIS (Netherlands)

    Pei, Y.T.; Hosson, J.Th.M. De

    2000-01-01

    Al-40Si functionally graded coatings produced by a one-step laser powder cladding process on cast aluminum-alloy substrate is a possible solution for avoiding the interfacial problems often present in laser coatings. The microstructure of the coatings consists of a large amount of silicon-primary

  4. Experimental Study on HSM 40CrNiMoA%高速铣削硬态40CrNiMoA的试验研究

    Institute of Scientific and Technical Information of China (English)

    查文炜

    2006-01-01

    针对硬态40CrNiMoA(47 HRC),在干切和空气油雾环境下,选用黛杰整体硬质合金(K30)涂层(涂层材料为TiNlN)立铣刀在Mikron UCP 710高速加工中心上作了试验研究.并通过试验结果对两种铣削环境下的铣削力作了比较,得出不同铣削参数和铣削环境下高速铣削硬态40CrNiMoA(47 HRC)铣削力的变化规律.

  5. SHS-PHIP法制备TiC-Ni(Mo)金属陶瓷%Preparation of TiC-Ni(Mo) Cermet Via SHS-PHIP

    Institute of Scientific and Technical Information of China (English)

    栾振涛; 周丽; 殷凤仕; 李树军

    2003-01-01

    采用Ti粉、碳黑、Ni粉和Mo粉的混合物,通过自蔓延高温合成(SHS)结合准等静压(PHIP)方法制备了TiC-Ni(Mo)金属陶瓷材料.X射线衍射结果表明,材料由TiC相和Ni合金粘结相组成.扫描电镜观察,球形的TiC颗粒较均匀地分布在Ni合金粘结相中,TiC颗粒尺寸约为2~4 μm,在局部较大的TiC颗粒之间存在微孔缺陷.SHS-PHIP法制备的TiC-Ni(Mo)金属陶瓷材料具有良好的致密性和优良的力学性能.

  6. Properties of multilayer coatings produced by coaxial laser cladding

    Science.gov (United States)

    Petrovskiy, V. N.; Bykovskiy, D. P.; Dzhumaev, P. S.; Polskiy, V. I.; Prokopova, N. M.; Chirikov, S. N.

    2016-09-01

    This article contains results of the study of multilayer coatings produced by laser cladding on the substrate steel 34HMA using iron based powder PR-10R6M5 as the filler material. The coatings were produced with consistent application of the tracks with fixed overlapping. The dependencies between the characteristics of tracks and the technological mode of deposition were revealed. Properties of coatings were determined for various overlapping of tracks and directions of the cladding layers.

  7. 酸度对化学镀Ni-P和Ni-Mo-P的影响%Effect of acidity on Ni-P and Ni-Mo-P chemical plating

    Institute of Scientific and Technical Information of China (English)

    方永奎; 邱安娥; 张翼; 邱万忠

    2002-01-01

    研究了镀液pH值对Ni-P和Ni-Mo-P化学镀镀层的生成速度和镀层中Ni质量分数的影响. 结果表明,镀液的pH值不仅影响Ni的沉积速度,而且影响镀层中Ni的质量分数;镀层生成速度均随镀液pH值增大而出现极大值,但两者的位置有所不同;随镀液pH值增加,Ni-Mo-P镀镀层中w(Ni)出现极大值,而Ni-P镀则是pH值增至一定值后w(Ni)趋于平稳;镀层的生成速度与镀层中w(Ni)的最高点都出现在相同的酸度下,Ni-P镀镀液的最佳pH值为5.5,而Ni-Mo-P镀镀液的最佳pH值为6.5.

  8. Method of Producing Controlled Thermal Expansion Coat for Thermal Barrier Coatings

    Science.gov (United States)

    Brindley, William J. (Inventor); Miller, Robert A. (Inventor); Aikin, Beverly J. M. (Inventor)

    2000-01-01

    An improved thermal barrier coating and method for producing and applying such is disclosed herein. The thermal barrier coatings includes a high temperature substrate, a first bond coat layer applied to the substrate of MCrAlX and a second bond coat layer of MCrAlX with particles of a particulate dispersed throughout the MCrAlX and the preferred particulate is Al2O3. The particles of the particulate dispersed throughout the second bond coat layer preferably have a diameter of less then the height of the peaks of the second bond coat layer or a diameter of less than 5 micron. The method of producing the second bond coat layer may either include the steps of mechanical alloying of particles throughout the second bond coat layer, attrition milling the particles of the particulate throughout the second bond coat layer, or using electrophoresis to disperse the particles throughout the second bond coat layer. In the preferred embodiment of the invention the first bond coat layer is applied to the substrate. and then the second bond coat layer is thermally sprayed onto the first bond coat layer. Further, in a preferred embodiment of the invention a ceramic insulating layer covers the second bond coat layer.

  9. Enhancement of the Hydrogen Evolution Reaction from Ni-MoS2 Hybrid Nanoclusters

    Science.gov (United States)

    2016-01-01

    This report focuses on a novel strategy for the preparation of transition metal–MoS2 hybrid nanoclusters based on a one-step, dual-target magnetron sputtering, and gas condensation process demonstrated for Ni-MoS2. Aberration-corrected STEM images coupled with EDX analysis confirms the presence of Ni and MoS2 in the hybrid nanoclusters (average diameter = 5.0 nm, Mo:S ratio = 1:1.8 ± 0.1). The Ni-MoS2 nanoclusters display a 100 mV shift in the hydrogen evolution reaction (HER) onset potential and an almost 3-fold increase in exchange current density compared with the undoped MoS2 nanoclusters, the latter effect in agreement with reported DFT calculations. This activity is only reached after air exposure of the Ni-MoS2 hybrid nanoclusters, suggested by XPS measurements to originate from a Ni dopant atoms oxidation state conversion from metallic to 2+ characteristic of the NiO species active to the HER. Anodic stripping voltammetry (ASV) experiments on the Ni-MoS2 hybrid nanoclusters confirm the presence of Ni-doped edge sites and reveal distinctive electrochemical features associated with both doped Mo-edge and doped S-edge sites which correlate with both their thermodynamic stability and relative abundance.

  10. Structural, Optical, and Magnetic Properties of NiMoO4 Nanorods Prepared by Microwave Sintering

    Directory of Open Access Journals (Sweden)

    Ana P. de Moura

    2015-01-01

    Full Text Available We report on the structural, optical, and magnetic properties of α,β-NiMoO4 nanorods synthesized by annealing the NiMoO4:nH2O precursor at 600°C for 10 minutes in a domestic microwave. The crystalline structure properties of α,β-NiMoO4 were investigated using X-ray diffraction (XRD, Fourier transform infrared (FTIR, and Raman (FT-Raman spectroscopies. The particle morphologies and size distributions were identified by field emission microscopy (FE-SEM. Experimental data were obtained by magnetization measurements for different applied magnetic fields. Optical properties were analyzed by ultraviolet-visible (UV-vis and photoluminescence (PL measurements. Our results revealed that the oxygen atoms occupy different positions and are very disturbed in the lattice and exhibit a particular characteristic related to differences in the length of the chemical bonds (Ni-O and Mo-O of the cluster structure or defect densities in the crystalline α,β-NiMoO4 nanorods, which are the key to a deeper understanding of the exploitable physical and chemical properties in this study.

  11. Anodization process produces opaque, reflective coatings on aluminum

    Science.gov (United States)

    1965-01-01

    Opaque, reflective coatings are produced on aluminum articles by an anodizing process wherein the anodizing bath contains an aqueous dispersion of finely divided insoluble inorganic compounds. These particles appear as uniformly distributed occlusions in the anodic deposit on the aluminum.

  12. NiMoO{sub 4} nanofibres designed by electrospining technique for glucose electrocatalytic oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Sheng-Hui; Lu, Shi-Yu; Bao, Shu-Juan, E-mail: baoshj@swu.edu.cn; Yu, Ya-Nan; Wang, Min-Qiang

    2016-01-28

    Electrochemical oxidation of glucose is the guarantee to realize nonenzymatic sensing of glucose, but greatly hindered by the slow kinetics of its oxidation process. Herein, various nanomaterials were designed as catalysts to accelerate glucose oxidation reaction. However, how to effectively build an excellent platform for promoting the glucose oxidation is still a great challenge. In our work, 1D CaMoO{sub 4} and NiMoO{sub 4} nanofibres with same morphologies and sub-microstructures were fabricated by electrospinning technique in the first time, and explored to modify the detection electrodes of nonenzymatic glucose sensors. The electrochemical results indicated that the NiMoO{sub 4} based sensor exhibited a good catalytic activity toward glucose including the low response potential (0.5 V), high sensitivity(193.8 μA mM{sup −1} cm{sup −2}) with a linear response region of 0.01–8 mM, low detection limit (4.6 μM) and fast response time (2 s), all of which are superior to the corresponding values of CaMoO{sub 4} nanofibres and even higher than those of most reported NiO and Co{sub 3}O{sub 4} catalysts, which is due to the NiMoO{sub 4} nanofibres are not only advantageous to electron transfer, but can mediated the electrocatalytic reaction of glucose. This work should provide a new pathway for the design of advanced glucose catalysts for nonenzymatic sensor. - Graphical abstract: Electrocatalytic reaction of NiMoO{sub 4} based non-enzymatic glucose sensor. - Highlights: • 1D NiMoO{sub 4} nanofibres were fabricated by electrospinning technique in the first time. • 1D NiMoO{sub 4} nanofibres were applied in nonenzymatic glucose sensors firstly. • A possible electrocatalytic mechanism of the nanoparticles for the glucose oxidation was proposed. • This work holds great promise for development advanced glucose catalysts for nonenzymatic sensor.

  13. Electrodeposition and Characterization of Nanocrystalline Ni-Mo Catalysts for Hydrogen Production

    Directory of Open Access Journals (Sweden)

    J. Halim

    2012-01-01

    Full Text Available Ni-Mo nanocrystalline deposits (7–43 nm with a nodular morphology were prepared by electrodeposition using direct current from citrate-ammonia solutions. They exhibited a single Ni-Mo solid solution phase. The size of the nodules increased as electroplating current density increased. The molybdenum content—estimated using EDX analysis—in the deposits decreased from about 31 to 11 wt% as the current density increased from 5 to 80 mA·cm−2. The highest microhardness value (285 Hv corresponded to nanodeposits with 23% Mo. The highest corrosion resistance accompanied by relatively high hardness was detected for electrodeposits containing 15% Mo. Mo content values between 11 and 15% are recommended for obtaining better electrocatalytic activity for HER.

  14. Magnetic field effects on the electrodeposition of CoNiMo alloys

    Science.gov (United States)

    Aaboubi, Omar; Msellak, Khalid

    2017-02-01

    In this work we have examined the influence of applying homogeneous magnetic field (MF) up to 1.2T, on Cobalt- Nickel-Molybdenum (CoNiMo) alloys electrodeposition from citric bath. The surface morphology, chemical composition and the crystallographic texture has been investigated by X-ray diffraction (XRD), X-ray composition mapping and scanning electron microscopy (SEM) images. The mass transport behaviour during the electrodeposition process has been examined through the polarization curves and electrochemical impedance methods. As expected, under MF control an enhancement in the mass transport rate was observed leading to grains refinement and homogeneous distribution of the Co, Mo and Ni atoms in the obtained CoNiMo films. These findings highlight the synergistic combination of Ni, Co and Mo by promoting the MHD convection due to the Lorentz force acting during the Ni(II) and Co(II) ions reduction.

  15. Determination of isothermal sections of the Co-Nb-Ni and Ni-Mo-Re ternary systems

    Institute of Scientific and Technical Information of China (English)

    FENG Yan; WANG Richu; YU Kun; WEN Danhua

    2008-01-01

    The isothermal sections of the Co-Nb-Ni ternary system at 1373 K and the Ni-Mo-Re ternary system at 1473 K were determined by means of diffusion triple and electron probe microanalysis (EPMA).The results indicate that there are three three-phase regions found in the Co-Nb-Ni ternary system at 1373 K:(Ni,Co)+NbCo3+ Ni3Nb,NbCo3+NbCo2+Ni3Nb,and NbCo2+μ+Ni3Nb;and four three-phase regions found in the Ni-Mo-Re ternary system at 1473 K:Re+Ni+χ,Ni+NiMo+σ,σ+χ+ Ni,and σ+Mo+NiMo.No ternary eompoond is observed in the two isothermal sections.The isothermal sections arc contrasted with the previous study.

  16. Preparation and evaluation of sulfided NiMo/γ-Al2O3 hydrotreating catalysts

    OpenAIRE

    KAMYAB, ALI

    2016-01-01

      Four nickel-molybdenum catalysts were synthesized on gamma alumina with higher surface area and on NiMo catalyst was prepared using gamma alumina with lower surface area. Catalysts with higher-surface-area support were prepared by co-impregnation, sequential impregnation and adding phosphorous. Theses catalysts were calcined at 500  ͦC. Effect of higher calcination temperature was investigated by preparation of one catalyst calcined at 700 ͦC. Catalysts were thoroughly characterized via fou...

  17. KINETIKA HIDRODESULFURISASI DIBENZOTHIOPHENE (HDS DBT MENGGUNAKAN KATALIS NiMo/γ-Al2O3

    Directory of Open Access Journals (Sweden)

    Subagjo Subagjo

    2014-12-01

    Full Text Available Evaluasi kinetika reaksi hidrodesulfurisasi (HDS dibenzothiophene dan simulasi nafta hydrotreater yang berada di PT. PERTAMINA Refinery Unit II Dumai menggunakan katalis NiMo/Al2O3 hasil pengembangan telah dilakukan. Kinetika reaksi HDS DBT dilakukan dalan sistem reaktor batch dengan variasi temperatur 280-320oC dan tekanan 30 bar. Data kinetika diolah dengan persamaan hukum pangkat (law power dan persamaan kinetik mekanistik (Langmuir Hinshelwood, LH. Berdasarkan model hukum pangkat, kinetika HDS DBT menggunakan NiMo/Al2O3 hasil pengembangan merupakan  orde satu  terhadap DBT dengan konstanta Arhenius  sebesar 165633 detik-1 dan energi aktivasi 69017 J/mol (16,56 kkal/mol. Model LH yang cocok untuk reaksi HDS DBT menggunakan NiMo/Al2O3 hasil pengembangan adalah model LH yang mengilustrasikan adanya kompetisi antara reaktan DBT dan H2 pada tipe pusat aktif yang sama, dengan DBT teradsorb secara kuat sedangkan H2 teradsorpsi secara lemah. Energi aktifasi dan konstanta Arhenius berdasarkan model LH ini ini berturut-turut adalah 81409 J/mol (19,34 kkal/mol dan 1658133 s-1. Dengan menggunakan persamaan laju reaksi hukum pangkat, model memberikan hasil konversi sulfur yang sama dengan hasil keluaran reaktor nafta hydrotreater RU II-Dumai, yaitu mencapai 98%.

  18. Synthesis of supported and unsupported NiMo carbides and their properties for the catalytic hydrocracking of n-octane

    Energy Technology Data Exchange (ETDEWEB)

    Torre, A I Reyes de la [Instituto Tecnologico de Ciudad Madero, Division de Estudios de Posgrado e Investigacion, Juventino Rosas y Jesus Urueta S/N, Colonia Los Mangos, CP 89440, Ciudad Madero, Tamaulipas (Mexico); Banda, J A Melo [Instituto Tecnologico de Ciudad Madero, Division de Estudios de Posgrado e Investigacion, Juventino Rosas y Jesus Urueta S/N, Colonia Los Mangos, CP 89440, Ciudad Madero, Tamaulipas (Mexico); Alamilla, R GarcIa [Instituto Tecnologico de Ciudad Madero, Division de Estudios de Posgrado e Investigacion, Juventino Rosas y Jesus Urueta S/N, Colonia Los Mangos, CP 89440, Ciudad Madero, Tamaulipas (Mexico); Sandoval Robles, G [Instituto Tecnologico de Ciudad Madero, Division de Estudios de Posgrado e Investigacion, Juventino Rosas y Jesus Urueta S/N, Colonia Los Mangos, CP 89440, Ciudad Madero, Tamaulipas (Mexico); Rojas, E Terres [Instituto Mexicano del Petroleo, Molecular Engineering Program, 152 Eje Central L Cardenas, 07730 San Bartolo Atepehuacan, Delegacion Gustavo A Madero, Mexico DF (Mexico); Lopez Ortega, A [Instituto Mexicano del Petroleo, Molecular Engineering Program, 152 Eje Central L Cardenas, 07730 San Bartolo Atepehuacan, Delegacion Gustavo A Madero, Mexico DF (Mexico); Dominguez, J M [Instituto Mexicano del Petroleo, Molecular Engineering Program, 152 Eje Central L Cardenas, 07730 San Bartolo Atepehuacan, Delegacion Gustavo A Madero, Mexico DF (Mexico)

    2004-06-09

    Unsupported and {gamma}-Al{sub 2}O{sub 3}-, MCM-41-supported (Ni, Mo) carbides were prepared and modified by 'in situ' polymer (PAN: polyacrylonitrile) pyrolysis. The supported catalysts were impregnated with Ni and Mo metals, i.e. 2.8 atom Mo/nm{sup 2}, whose atomic ratio was Ni/Ni+Mo = 0.5. X-ray diffraction (XRD) showed single NiC, MoC phases in all cases, with relatively low surface areas, as verified by N{sub 2} adsorption (BET). The catalytic behaviour of the supported (Ni, Mo)C phases for n-C{sub 8} hydrocracking depended on the support type. (Ni, Mo)C/MCM41-PAN-P (P = pyrolyzed) showed a total conversion of 40% while it was only 15% on Ni,MoC/{gamma}-Al{sub 2}O{sub 3}. The most active catalysts were (Ni, Mo)C unsupported catalysts, i.e., 90% total conversion. In all cases the hydrocracking selectivity favoured lighter hydrocarbons (C{sub 1}-C{sub 4})

  19. Fabrication of Low Adsorption Energy Ni-Mo Cluster Cocatalyst in Metal-Organic Frameworks for Visible Photocatalytic Hydrogen Evolution.

    Science.gov (United States)

    Zhen, Wenlong; Gao, Haibo; Tian, Bin; Ma, Jiantai; Lu, Gongxuan

    2016-05-04

    An effective cocatalyst is crucial for enhancing the visible photocatalytic performance of the hydrogen generation reaction. By using density-functional theory (DFT) and frontier molecular orbital (FMO) theory calculation analysis, the hydrogen adsorption free energy (ΔGH) of Ni-Mo alloy (458 kJ·mol(-1)) is found to be lower than that of Ni itself (537 kJ·mol(-1)). Inspired by these results, the novel, highly efficient cocatalyst NiMo@MIL-101 for photocatalysis of the hydrogen evolution reaction (HER) was fabricated using the double solvents method (DSM). In contrast with Ni@MIL-101 and Mo@MIL-101, NiMo@MIL-101 exhibited an excellent photocatalytic performance (740.2 μmol·h(-1) for HER), stability, and high apparent quantum efficiency (75.7%) under 520 nm illumination at pH 7. The NiMo@MIL-101 catalyst also showed a higher transient photocurrent, lower overpotential (-0.51 V), and longer fluorescence lifetime (1.57 ns). The results uncover the dependence of the photocatalytic activity of HER on the ΔGH of Ni-Mo (MoNi4) alloy nanoclusters, i.e., lower ΔGH corresponding to higher HER activity for the first time. The NiMo@MIL-101 catalyst could be a promising candidate to replace precious-metal catalysts of the HER.

  20. Laser Hardening Technology for 40CrNiMoA Steel%40CrNiMoA钢激光相变硬化技术

    Institute of Scientific and Technical Information of China (English)

    石岩; 徐春鹰; 张宏

    2002-01-01

    研究了40CrNiMoA钢激光淬火工艺参数与硬化层深度及硬度之间的相互关系,以及淬硬层微观结构特征.结果表明,随着光斑扫描速度的提高,硬化层深度降低,表面硬度存在一个极大值;随着激光功率的升高,硬化层深度增加,表面硬度也存在一个极大值;激光淬火硬化层依其组织特征,分为完全淬硬区、过渡区及高温回火区.

  1. Apparatus for producing carbon-coated nanoparticles and carbon nanospheres

    Energy Technology Data Exchange (ETDEWEB)

    Perry, W. Lee; Weigle, John C.; Phillips, Jonathan

    2015-10-20

    An apparatus for producing carbon-coated nano- or micron-scale particles comprising a container for entraining particles in an aerosol gas, providing an inlet for carbon-containing gas, providing an inlet for plasma gas, a proximate torch for mixing the aerosol gas, the carbon-containing gas, and the plasma gas, bombarding the mixed gases with microwaves, and providing a collection device for gathering the resulting carbon-coated nano- or micron-scale particles. Also disclosed is a method and apparatus for making hollow carbon nano- or micro-scale spheres.

  2. Development of FeNiMoB thin film materials for microfabricated magnetoelastic sensors

    KAUST Repository

    Liang, Cai

    2012-12-07

    MetglasTM 2826MB foils of 25–30 μm thickness with the composition of Fe40Ni38Mo4B18 have been used for magnetoelastic sensors in various applications over many years. This work is directed at the investigation of ∼3 μm thick iron-nickel-molybdenum-boron (FeNiMoB) thin films that are intended for integrated microsystems. The films are deposited on Si substrate by co-sputtering of iron-nickel (FeNi), molybdenum(Mo), and boron (B) targets. The results show that dopants of Mo and B can significantly change the microstructure and magnetic properties of FeNi materials. When FeNi is doped with only Mo its crystal structure changes from polycrystalline to amorphous with the increase of dopant concentration; the transition point is found at about 10 at. % of Mo content. A significant change in anisotropic magneticproperties of FeNi is also observed as the Modopant level increases. The coercivity of FeNi filmsdoped with Mo decreases to a value less than one third of the value without dopant.Doping the FeNi with B together with Mo considerably decreases the value of coercivity and the out-of-plane magnetic anisotropyproperties, and it also greatly changes the microstructure of the material. In addition, doping B to FeNiMo remarkably reduces the remanence of the material. The filmmaterial that is fabricated using an optimized process is magnetically as soft as amorphous MetglasTM 2826MB with a coercivity of less than 40 Am−1. The findings of this study provide us a better understanding of the effects of the compositions and microstructure of FeNiMoB thin filmmaterials on their magnetic properties.

  3. Magnetic behaviour of AuFe and NiMo alloys

    Indian Academy of Sciences (India)

    Prashant Singh; Rudra Banerjee; Moshiour Rahaman; A V Ruban; Biplab Sanyal; Abhijit Mookerjee

    2011-04-01

    We study the electronic structure and a mean-field phase analysis based on the pair–pair energies derived from first-principles electronic structure calculations of AuFe and NiMo alloys. We have used the tight-binding linear muffin-tin orbitals-based augmented space recursion (TB-LMTO-ASR) method to do so. We investigate different behaviours of the two alloy systems by mapping the problems onto equivalent Ising models and then discuss the magnetic phase diagrams using the calculated pair energies. All three phases: paramagnetic, random ferromagnetic and spin glass, have been studied.

  4. Microstructure and pitting corrosion of 13CrNiMo weld metals

    Energy Technology Data Exchange (ETDEWEB)

    Bilmes, P.D. [Laboratorio de Investigaciones de Metalurgia Fisica ' Ing. Gregorio Cusminsky' (LIMF), Departamento Mecanica, Facultad de Ingenieria, Universidad Nacional de la Plata, calle 1 y 47, 1900 La Plata (Argentina); Llorente, C.L. [Laboratorio de Investigaciones de Metalurgia Fisica ' Ing. Gregorio Cusminsky' (LIMF), Departamento Mecanica, Facultad de Ingenieria, Universidad Nacional de la Plata, calle 1 y 47, 1900 La Plata (Argentina); Saire Huaman, L. [Instituto de Investigaciones, Fisicoquimicas Teoricas y Aplicadas (INIFTA), Facultad de Ciencias Exactas, Universidad Nacional de la Plata, Sucursal 4-C.C. 16, 1900 La Plata (Argentina); Laboratorio de Ingenieria de Corrosion y Tecnologia Electroquimica (LICTE), Departamento Ingenieria Quimica, Facultad de Ingenieria, Universidad Nacional de la Plata, 1 y 47, 1900 La Plata (Argentina); Gassa, L.M. [Instituto de Investigaciones, Fisicoquimicas Teoricas y Aplicadas (INIFTA), Facultad de Ciencias Exactas, Universidad Nacional de la Plata, Sucursal 4-C.C. 16, 1900 La Plata (Argentina); Laboratorio de Ingenieria de Corrosion y Tecnologia Electroquimica (LICTE), Departamento Ingenieria Quimica, Facultad de Ingenieria, Universidad Nacional de la Plata, 1 y 47, 1900 La Plata (Argentina); Gervasi, C.A. [Instituto de Investigaciones, Fisicoquimicas Teoricas y Aplicadas (INIFTA), Facultad de Ciencias Exactas, Universidad Nacional de la Plata, Sucursal 4-C.C. 16, 1900 La Plata (Argentina) and Laboratorio de Ingenieria de Corrosion y Tecnologia Electroquimica (LICTE), Departamento Ingenieria Quimica, Facultad de Ingenieria, Universidad Nacional de la Plata, 1 y 47, 1900 La Plata (Argentina)]. E-mail: gervasi@inifta.unlp.edu.ar

    2006-10-15

    Cyclic potentiodynamic measurements and scanning electron microscopy were used to analyze susceptibility to pitting corrosion of 13CrNiMo weld metals. In order to carry out a critical assessment of the influence of microstructural factors on localized corrosion, different heat treatments were applied to the alloys under investigation. Volume fractions of austenite in tempered conditions as well as the amount and size of precipitated carbides strongly affect pitting resistance. Characteristic potentials (pitting potential and repassivation potential) increase according to the retained austenite content. Results can be discussed in terms of a model that describes the structural refinement resulting from a double-tempering procedure.

  5. Leaching kinetics of molybdenum from Ni-Mo ore in sulfuric acid solution with sodium peroxodisulfate as oxidant

    Institute of Scientific and Technical Information of China (English)

    刘志雄; 尹周澜; 陈义光; 熊利芝

    2015-01-01

    The leaching kinetics of molybdenum from Ni-Mo ore in sulfuric acid solution with sodium peroxodisulfate was studied. The effects including leaching temperature, reaction time, particle size, stirring speed, and concentrations of sulfuric acid and sodium peroxodisulfate were investigated. The leaching process of molybdenum from Ni-Mo ore is controlled by the chemical reaction through the solid layer across the unreacted shrinking core. The apparent activation energy of the leaching of molybdenum is calculated to be 41.0 kJ/mol and the leaching kinetics equation of molybdenum from Ni-Mo ore is expressed as 1−(1−a)1/3=3405.7exp[−41030.0/(RT)]t.

  6. Synthesis, surface structure and optical properties of double perovskite Sr2NiMoO6 nanoparticles

    Science.gov (United States)

    Xu, Lei; Wan, Yingpeng; Xie, Hongde; Huang, Yanlin; Yang, Li; Qin, Lin; Seo, Hyo Jin

    2016-12-01

    Double perovskite Sr2NiMoO6 nanoparticles were synthesized via the chemical sol-gel route. The phase formation was investigated through X-ray polycrystalline diffraction (XRD) and Rietveld refinements. The perovskite crystallized in worm-like nano-grains with the diameter of 20-50 nm. The optical properties were measured by the optical absorption spectra. The nanoparticles present an indirect allowed transition with a narrow band gap of 2.1 eV. Sr2NiMoO6 nanoparticles have obvious photocatalytic ability on the degradation of Rhodamine B (RhB) solutions under the irradiation of visible light. The transport behaviors of the excitons were investigated from the photoluminescence spectra and the corresponding decay lifetimes. Sr2NiMoO6 nanoparticles present several advantages for photocatalysis such as the appropriate band energy positions, the quenched luminescence, and the coexistence of multivalent ions in the lattices.

  7. Exchange bias in zinc ferrite-FeNiMoB based metallic glass composite thin films

    Energy Technology Data Exchange (ETDEWEB)

    R, Lisha; P, Geetha; B, Aravind P.; Anantharaman, M. R., E-mail: mraiyer@yahoo.com [Cochin University of Science and Technology, Cochin-682022 (India); T, Hysen [Christian College, Chengannur, Kerala-689121 (India); Ojha, S.; Avasthi, D. K. [Inter University Accelerator Centre, Vasant Kunj, New Delhi-110067 (India); Ramanujan, R. V. [School of Materials Science and Engineering, Nanyang Technological University (Singapore)

    2015-06-24

    The Exchange bias phenomenon and methods to manipulate the bias field in a controlled manner are thrust areas in magnetism due to its sophisticated theoretical concepts as well as advanced technological utility in the field of spintronics. The Exchange bias effect is observed as a result of ferromagnetic-antiferromagnetic (FM-AFM) exchange interaction, usually observed as a loop shift on field cooling below the Neel temperature of AFM. In the present study, we have chosen zinc ferrite which is a well known antiferromagnet, and FeNiMoB based metallic glass as the ferromagnet. The films were prepared by RF sputtering technique. The thickness and composition was obtained by RBS. The magnetic studies using SQUID VSM indicate exchange bias effect in the system. The effect of thermal annealing on exchange bias effect was studied. The observed exchange bias in the zinc ferrite-FeNiMoB system is not due to FM-AFM coupling but due to spin glass-ferromagnetic interaction.

  8. Thermal Stability of Intermetallic Phases in Fe-rich Fe-Cr-Ni-Mo Alloys

    Science.gov (United States)

    Yang, Ying; Tan, Lizhen; Busby, Jeremy T.

    2015-09-01

    Understanding the thermal stability of intermetallic phases in Fe-rich Fe-Cr-Ni-Mo alloys is critical to alloy design and application of Mo-containing austenitic steels. Coupled with thermodynamic modeling, the thermal stability of intermetallic Chi and Laves phases in two Fe-Cr-Ni-Mo alloys was investigated at 1273 K, 1123 K, and 973 K (1000 °C, 850 °C, and 700 °C) for different annealing times. The morphologies, compositions, and crystal structures of the precipitates of the intermetallic phases were carefully examined by scanning electron microscopy, electron probe microanalysis, X-ray diffraction, and transmission electron microscopy. Two key findings resulted from this study. First, the Chi phase is stable at high temperature, and with the decreasing temperature it transforms into the Laves phase that is stable at low temperature. Secondly, Cr, Mo, and Ni are soluble in both the Chi and Laves phases, with the solubility of Mo playing a major role in the relative stability of the intermetallic phases. The thermodynamic models that were developed were then applied to evaluating the effect of Mo on the thermal stability of intermetallic phases in type 316 and NF709 stainless steels.

  9. Mechanical properties of Cr-Cu coatings produced by electroplating

    Science.gov (United States)

    Riyadi, Tri Widodo Besar; Sarjito, Masyrukan, Riswan, Ricky Ary

    2017-06-01

    Hard chromium coatings has long been considered as the most used electrodeposited coating in several industrial applications such as in petrochemistry, oil and gas industries. When hard coatings used in fastener components, the sliding contact during fastening operation produces high tensile stresses on the surface which can generate microcracks. For component used in high oxidation and corrosion environment, deep cracks cannot be tolerated. In this work, a laminated structure of Cr-Cu coating was prepared using electroplating on carbon steel substrates. Two baths of chrome and copper electrolyte solutions were prepared to deposit Cr as the first layer and Cu as the second layer. The effect of current voltages on the thickness, hardness and specific wear rate of the Cu layer was investigated. The results show that an increase of the current voltages increased the thickness and hardness of the Cu layer, but reduced the specific wear rate. This study showed that the use of Cu can be a potential candidate as a laminated structure Cr-Cu for chromium plating.

  10. Comprehensive Utilization Process and Research Status of Ni-Mo Ore%镍钼矿综合利用过程及研究现状

    Institute of Scientific and Technical Information of China (English)

    王明玉; 王学文; 蒋长俊; 马艺骞; 樊烨烨; 向小艳

    2012-01-01

    treating Ni-Mo ore was reduction smelting to produce ferromolybdenum and sodium salt roasting-water leaching for producing molybdenum oxide, but in the process the exhaust gas containing SO2 was produced which polluted the environment and also the product class was low. At present, the extraction of molybdenum from Ni-Mo ore was mainly by alkaline leaching with oxygen pressure technique and the oxidizing roasting-alkali leaching technique etc. For getting high quality ammonium molybdate as well as high molybdenum recovery, but nickel did not recycle in these processes. The calcified roasting-low temperature sulphation roasting-water leaching technique could recover molybdenum and nickel synchronously, and the recovery of nickel and molybdenum could reach 92% and 96% , respectively, at the same time, this technique was characterized by low pollution, short process and low production cost. In addition, the biological metallurgy technique also showed a good application prospect.

  11. Amorphous boron coatings produced with vacuum arc deposition technology

    CERN Document Server

    Klepper, C C; Yadlowsky, E J; Carlson, E P; Keitz, M D; Williams, J M; Zuhr, R A; Poker, D B

    2002-01-01

    In principle, boron (B) as a material has many excellent surface properties, including corrosion resistance, very high hardness, refractory properties, and a strong tendency to bond with most substrates. The potential technological benefits of the material have not been realized, because it is difficult to deposit it as coatings. B is difficult to evaporate, does not sputter well, and cannot be thermally sprayed. In this article, first successful deposition results from a robust system, based on the vacuum (cathodic) arc technology, are reported. Adherent coatings have been produced on 1100 Al, CP-Ti, Ti-6Al-4V, 316 SS, hard chrome plate, and 52 100 steel. Composition and thickness analyses have been performed by Rutherford backscattering spectroscopy. Hardness (H) and modules (E) have been evaluated by nanoindentation. The coatings are very pure and have properties characteristic of B suboxides. A microhardness of up to 27 GPa has been measured on a 400-nm-thick film deposited on 52 100 steel, with a corresp...

  12. The contribution of dislocation - Impurities interaction to kinetics of martensitic transformation of quenched fcc Fe-Ni-Mo alloys

    NARCIS (Netherlands)

    Golovin, [No Value; Goncharov, S; Golovin, SA

    1996-01-01

    The kinetics of martensitic transformation in austenitic Fe-Ni-Mo alloys depends on the carbon content. Analysis of carbon redistribution between f.c.c. solid solution and dislocation has been carried out with the help of internal friction (amplitude and temperature effects) study and stress relaxat

  13. Deactivation of Ni-MoS2 by bio-oil impurities during hydrodeoxygenation of phenol and octanol

    DEFF Research Database (Denmark)

    Mortensen, Peter Mølgaard; Gardini, Diego; Damsgaard, Christian Danvad

    2016-01-01

    The stability of Ni-MoS2/ZrO2 toward water, potassium, and chlorine containing compounds during hydrodeoxygenation (HDO) of a mixture of phenol and 1-octanol was investigated in a high pressure gas and liquid continuous flow fixed bed setup at 280 °C and 100 bar. To maintain the stability...

  14. Solvent free depolymerization of Kraft lignin to alkyl-phenolics using supported NiMo and CoMo catalysts

    NARCIS (Netherlands)

    Kumar, Chowdari Ramesh; Anand, Narani; Kloekhorst, Arjan; Cannilla, Catia; Bonura, Giuseppe; Frusteri, Francesco; Barta, Katalin; Heeres, Hero Jan

    2015-01-01

    The catalytic hydrotreatment of Kraft lignin using sulfided NiMo and CoMo catalysts on different acidic and basic supports (Al2O3, ZSM-5, activated carbon (AC) and MgO-La2O3) was studied in the absence of a solvent. Experiments were carried out in a batch set-up at a reaction temperature of 350

  15. Application of NiMoNb adhesion layer on plasma-treated polyimide substrate for flexible electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Bang, S.-H.; Kim, K.-K.; Jung, H.-Y.; Kim, T.-H.; Jeon, S.-H. [Metal and Material Technology Group, R and D Center, LS Mtron Ltd., Gyeonggi 431-080 (Korea, Republic of); Seol, Jae-Bok, E-mail: zptkfm20@hanmail.net [Max-Planck-Insititut für Eisenforschung, Max-Planck-Str. 1, D-40237 Düsseldorf (Germany)

    2014-05-02

    A thin film, NiMoNb, was introduced as an adhesion layer between the Cu metal and the insulator polyimide substrate in a flexible Cu-clad laminated structure. Using 90° peel test, we evaluated the peel strength of the system as a function of the thickness of the adhesion layer. An increase in the NiMoNb thickness from 7 to 40 nm enhanced the peel strength of the deposited systems. After plasma treatment by the roll-to-roll method, the multilayer structure showed an outstanding peel strength of ∼ 529 N/m, even after thermal annealing at 150 °C for 168 h. We also studied the role of plasma treatment of the polyimide substrate on the adhesion strength and microstructure of a flexible Cu-clad laminated structure by peel strength, atomic force microscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. These experimental observations showed that the plasma-treated polyimide substrate with the deposition of NiMoNb showed the enhanced adhesion of ∼ 656 N/m, because of the change of functional groups, which affected the bonding force and crystallinity of the thin films deposited on polyimide, rather than an increase in the surface roughness. - Highlights: • NiMoNb film on polyimide substrate was employed for higher peel strength. • Plasma-treated substrate enhances the peel strength of multilayer. • Even when annealed at 150 °C, plasma-treated films showed enhanced peel strength.

  16. Solvent free depolymerization of Kraft lignin to alkyl-phenolics using supported NiMo and CoMo catalysts

    NARCIS (Netherlands)

    Kumar, Chowdari Ramesh; Anand, Narani; Kloekhorst, Arjan; Cannilla, Catia; Bonura, Giuseppe; Frusteri, Francesco; Barta, Katalin; Heeres, Hero Jan

    2015-01-01

    The catalytic hydrotreatment of Kraft lignin using sulfided NiMo and CoMo catalysts on different acidic and basic supports (Al2O3, ZSM-5, activated carbon (AC) and MgO-La2O3) was studied in the absence of a solvent. Experiments were carried out in a batch set-up at a reaction temperature of 350 degr

  17. Monotonic and Cyclic Behavior of DIN 34CrNiMo6 Tempered Alloy Steel

    Directory of Open Access Journals (Sweden)

    Ricardo Branco

    2016-04-01

    Full Text Available This paper aims at studying the monotonic and cyclic plastic deformation behavior of DIN 34CrNiMo6 high strength steel. Monotonic and low-cycle fatigue tests are conducted in ambient air, at room temperature, using standard 8-mm diameter specimens. The former tests are carried out under position control with constant displacement rate. The latter are performed under fully-reversed strain-controlled conditions, using the single-step test method, with strain amplitudes lying between ±0.4% and ±2.0%. After the tests, the fracture surfaces are examined by scanning electron microscopy in order to characterize the surface morphologies and identify the main failure mechanisms. Regardless of the strain amplitude, a softening behavior was observed throughout the entire life. Total strain energy density, defined as the sum of both tensile elastic and plastic strain energies, was revealed to be an adequate fatigue damage parameter for short and long lives.

  18. Microstructure and Properties of FeAlCrNiMo x High-Entropy Alloys

    Science.gov (United States)

    Li, X. C.; Dou, D.; Zheng, Z. Y.; Li, J. C.

    2016-06-01

    FeAlCrNiMo x high-entropy alloys were prepared. The effect of Mo content on the microstructure and the properties of the alloys were investigated. When the Mo content was 0.1, the alloys were composed of single BCC solid solution; when Mo content reaches 0.25, the alloys were composed of BCC solid solution and ordered B2 solid solution. When Mo content is more than 0.75, some σ phases emerged. The volume fraction of the second phase increases with the increasing Mo content, and the crystal grains became coarsening. The yield strength, fracture strength, and hardness increase with the increasing Mo content and reach 2252, 2612 MPa, and 1006 Hv, respectively. The magnetic transformation undergoes from the ferromagnetism to paramagnetism with the increasing Mo content. The saturation intensity and remnant magnetism are decreased with the increasing Mo content.

  19. Development of banded microstructure in 34CrNiMo6 steel

    Directory of Open Access Journals (Sweden)

    A. Nagode

    2016-07-01

    Full Text Available In this paper the development of a banded microstructure in hot-rolled 34CrNiMo6 steel which consisted of bainitic and martensitic bands is explained. The chemical compositions of the bands were measured with energy dispersive x-ray spectroscopy (EDS, which showed that the martensitic bands contained more alloying elements (Mn, Cr, Mo, Si than bainitic bands. By using Oberhoffer reagent, the segregations of phosphorus were also revealed. These phosphorus segregations coincided with the positive segregations of the alloying elements. The continuous cooling transformation (CCT diagrams of steel were calculated. They confirmed the formation of martensite in positive segregations and the formation of bainite in negative segregations.

  20. Electrochemical investigations of Cr-Ni-Mo stainless steel used in urology

    Science.gov (United States)

    Przondziono, J.; Walke, W.

    2011-05-01

    The influence of chemical passivation process on physical and chemical characteristics of samples made of X2CrNiMo 17-7-2 steel with differentiated hardening, in the solution simulating the environment of human urine was analysed in the study. Wire obtained in cold drawing process is used for the production of stents and appliances in urological treatment. Proper roughness of the surface was obtained through mechanical working - grinding (Ra = 0,40 μn) and electrochemical polishing (Ra = 0,12 μn). Chemical passivation process was carried out in 40% solution of HN03 within 60 minutes in the temperature of 65°C. The tests of corrosion resistance were made on the ground of registered anodic polarisation curves and Stern method. For evaluation of phenomena occurring on the surface of tested steel, electrochemical impedance spectroscopy (EIS) was applied.

  1. Electrochemical and metallurgical characterization of ZrCr{sub 1-x}NiMo{sub x} AB{sub 2} metal hydride alloys

    Energy Technology Data Exchange (ETDEWEB)

    Erika, Teliz [Universidad de la República, Facultad de Ciencias, Laboratorio de Electroquímica Fundamental, Núcleo Interdisciplinario Ingeniería Electroquímica, Igua 4225, CP 11400 Montevideo (Uruguay); Ricardo, Faccio [Universidad de la República, Crystallography, Solid State and Materials Laboratory (Cryssmat-Lab), DETEMA, Centro NanoMat, Polo Tecnológico de Pando, Espacio Interdisciplinario, Facultad de Química, Montevideo (Uruguay); Fabricio, Ruiz [Consejo Nacional de Investigaciones Científicas y Técnicas , CONICET, Av. Rivadavia 1917, C1033AAJ Ciudad de Buenos Aires (Argentina); Centro Atómico Bariloche , Comisión Nacional de Energía Atómica (CAB-CNEA), Av. Bustillo 9500, CP 8400 S.C. de Bariloche, RN (Argentina); Fernando, Zinola [Universidad de la República, Facultad de Ciencias, Laboratorio de Electroquímica Fundamental, Núcleo Interdisciplinario Ingeniería Electroquímica, Igua 4225, CP 11400 Montevideo (Uruguay); and others

    2015-11-15

    The effects of partial replacement of chromium by molybdenum was studied on the structure and electrochemical kinetic properties of ZrCr{sub 1-x}NiMo{sub x}(x = 0.0, 0.3 and 0.6) metal hydride alloys. The arc-melting prepared alloys were metallurgically characterized by X-ray diffraction and energy dispersive spectroscopy microanalysis, which showed AB{sub 2} (with hexagonal C14 structure) and Zr{sub x}Ni{sub y} (Zr{sub 7}Ni{sub 10}, Zr{sub 9}Ni{sub 11}) phases. After a partial substitution of chromium by molybdenum, secondary phases monotonically increase with the C14 unit cell volume indicating that most of molybdenum atoms locate in the B-site. The alloys were electrochemically characterized using charge/discharge cycling, electrochemical impedance spectroscopy and rate capability experiments that allowed the determination of hydriding reaction kinetic parameters. The presence of molybdenum produces a positive effect for hydrogen diffusion in the alloy lattice, and ZrCr{sub 0.7}NiMo{sub 0.3} alloy depicts the better kinetics associated with a fast activation, lower charge transfer resistance and the best high rate discharge behavior. This fact would be related to a lower diffusion time constant and a bigger value of the product between exchange density current and surface active area. There is a trade-off in the amounts of secondary phase and Laves phases in order to improve the kinetic performance. - Highlights: • Metallurgical characterization evidences the presence of Zr{sub x}Ni{sub y} and C14 phases. • The partial replacement of Cr by Mo promotes the segregation of Zr{sub x}Ni{sub y} phase. • The incorporation of molybdenum improves the kinetics for the hydriding process. • Mo produces a decrease in the diffusion time constant.

  2. On the kinetics of the hydrogen evolution reaction on Ni-MoOx composite catalysts in alkaline solutions

    Directory of Open Access Journals (Sweden)

    Jović Borka M.

    2012-01-01

    Full Text Available MoO3 particles were co-deposited with Ni onto smooth or rough Ni supports from modified Watt’s baths of different compositions. Morphology and composition of the electrodeposits were characterized by means of cyclic voltammetry, X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray spectroscopy. The electrocatalytic activity of the composite catalysts for H2 evolution in alkaline solutions was determined by quasi-stationary polarization curves. Activity increases with MoOx content in the Ni deposit up to a limiting value. Composite Ni-MoOx catalyst performed high catalytic activity, similar to that of commercial Ni-RuO2 catalyst. Stability tests showed that Ni-MoOx codeposits are stable under condition of constant current and exhibit excellent tolerance to repeated short-circuiting.

  3. Effects of Heat Treatment and Nitrogen on Microstructure and Mechanical Properties of 1Cr12NiMo Martensitic Stainless Steel

    National Research Council Canada - National Science Library

    Ruicheng Fan Ming Gao Yingche Ma Xiangdong Zha Xianchao Hao Kui Liu

    2012-01-01

    A series of heat treatments using the orthogonal experiment method were performed to study the microstruc- ture and mechanical properties of 1Cr12NiMo martensitic stainless steel containing various...

  4. Microstructural and mechanical characteristics of low alloyed Ni-Mo-Cu austempered ductile iron

    Energy Technology Data Exchange (ETDEWEB)

    Bosnjak, B.

    2000-12-01

    The present study investigated the effect of austempering temperature and austempering time on the microstructure and mechanical properties of low alloyed Ni-Mo-Cu ductile iron. The effect of austempering parameters and alloying additions on the austemperability of treated ductile iron has been estimated, too. Specimens were austenitised at 900 degree C for 120 mm, then austempered for 10, 30, 60, 120, 240 and 360 mm at 300, 350 and 400 degree C respectively, and examined by light and scanning electron microscopy. The structure consisted of bainitic ferrite containing retained austenite. the amount of which increased, and the carbon content of which decreased, with increasing austempering temperature. The carbon content of austenite has been evaluated by measuring the lattice parameter by X-ray diffraction. After short periods of austempering time in iron, the carbon content of the retained austenite decreases and on subsequent cooling to room temperature it transforms to martensite. The volume fractions of retained austenite, bainitic ferrite, martensite and austenite carbon content was correlated with microstructural changes and mechanical properties. Optimum properties are obtained at intermediate austempering periods (120-240 mm) when both the amount of retained austenite and austenite carbon content are maximum. (author)

  5. Rapid growth of nickel dendrite in highly undercooled Ni-Mo alloys

    Institute of Scientific and Technical Information of China (English)

    姚文静; 魏炳波

    2003-01-01

    Ni-39.3%Mo, Ni-45%Mo hypoeutectic alloys and Ni-47.7%Mo eutectic alloy have been rapidly solidified with different droplet sizes by containerless processing in a drop tube. For Ni-39.3%Mo hypoeutectic alloy, which corresponds to the maximum solid solubility of nickel phase, the solidification microstructure is characterized by nickel dendrite plus (Ni+NiMo) eutectic structure. The undercooling of this alloy up to 182 K has been realized in the experiments. With an increase in undercooling, the dendritic microstructure is refined. The microstructural evolution of primary Ni phase in Ni-45%Mo hypoeutectic alloy evolves from remelted dendrite to equiaxed grains, whereas Ni-47.7%Mo eutectic alloy exhibits a structural transition from lamellar eutectic to anomalous eutectic. Theoretical analyses indicate that, for Ni-39.3%Mo, Ni-45%Mo and Ni-47.7%Mo alloys, the nickel phase shows a transition from solutal-diffusion-controlled growth to thermal-diffusion-controlled growth at undercoolings of 66.6, 81.9 and 85.0 K. The critical transition temperature decreases with a reduction in the nickel content.

  6. Understanding the role of Co3O4 on stability between active hierarchies and scaffolds: An insight into NiMoO4 composites for supercapacitors

    Science.gov (United States)

    Zhao, Yuanyuan; Zhang, Peng; Fu, Wenbin; Ma, Xiangwen; Zhou, Jinyuan; Zhang, Xiaojuan; Li, Jian; Xie, Erqing; Pan, Xiaojun

    2017-09-01

    It is often reported that pseudocapacitive electrodes' mechanical stability seriously limited their cycling performances in supercapacitors due to their quick fall off the electrode matrix during frequent fast charge/discharge process. In this work, we have demonstrated the mechanical enhancement in hierarchical NiMoO4 nanosheet arrays (NSAs) on free-standing substrates after introducing Co3O4 hierarchies. Under sonication vibration environment, the mechanical stability of Co3O4@NiMoO4 NSAs was enhanced by ∼70% compared to that of the pure NiMoO4 ones. Moreover, the Co3O4@NiMoO4 NSAs can display a high specific capacitance of 1476 F g-1 at the current density of 1 A g-1, and an excellent rate capability (keeping 81% at 20 A g-1). And after 2000 cycles, high capacitance retention of 96% was achieved for the Co3O4@NiMoO4 core/shell NSAs, while only 70% for the pure NiMoO4 ones.

  7. Structure-property relationship of ceramic coatings on metals produced by laser processing

    NARCIS (Netherlands)

    de Hosson, J.T.M.; van den Burg, M.; Mazumder, J; Conde, O; Villar, R; Steen, W

    1996-01-01

    This paper concentrates on the mechanical performance of various ceramic coatings of Cr2O3 on steel (SAF2205), as produced by CO2 laser processing. The thickness of the coating that can be applied by laser coating is limited to about 200 mu m setting a limit to the maximum strain energy release rate

  8. Optically transparent, superhydrophobic, biocompatible thin film coatings and methods for producing same

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, Beth L.; Aytug, Tolga; Paranthaman, Mariappan Parans; Simpson, John T.; Hillesheim, Daniel A.; Trammell, Neil E.

    2017-09-05

    An optically transparent, hydrophobic coating, exhibiting an average contact angle of at least 100 degrees with a drop of water. The coating can be produced using low-cost, environmentally friendly components. Methods of preparing and using the optically transparent, hydrophobic coating.

  9. Development of Grain Boundary Precipitate-Free Zones in a Ni-Mo-Cr-W Alloy

    Science.gov (United States)

    Song, Jie; Field, Robert; Konitzer, Doug; Kaufman, Michael

    2017-02-01

    In this study, the morphology and development of precipitate-free zones (PFZs) near grain boundaries (GBs) in low coefficient of thermal expansion (CTE) Ni-Mo-Cr-W alloys (based on Haynes 244) have been investigated as a function of thermal history and composition using electron microscopy techniques. It is shown that the formation of wide, continuous PFZs adjacent to GBs can be largely attributed to a vacancy depletion mechanism. It is proposed that variations in the vacancy distributions that develop after solution heat treatment (SHT) and subsequent quenching and aging greatly influence the development of the γ'-Ni2(Mo,Cr) precipitates during the aging process and result in the development of PFZs of varying sizes. The relatively large (5 to 10 μm) PFZs are distinct from the smaller, more common PFZs that result from solute depletion due to GB precipitation that are typically observed after prolonged aging. During the course of this investigation, heat treatment parameters, such as aging time, SHT temperature, cooling rate after SHT, and heating rate to the aging temperature—all of which change vacancy concentration and distribution adjacent to GBs—were investigated and observed to have significant influence on both the size and morphology of the observed PFZs. In contrast to results from other Ni-based alloys studied previously, PFZ development in the current alloys was observed across a broad range of aging temperatures. This appears to be due to the high misfit strain energy of the γ' precipitates, resulting in a nucleation process that is sensitive to vacancy concentration. It is also shown that a slightly modified alloy with higher Mo concentrations develops smaller, more typical PFZs; this is presumably due to an increased driving force for γ' precipitation which overshadows the influence of misfit strain energy, thereby decreasing the sensitivity of precipitation on vacancy concentration.

  10. Characterization and Catalytic Activity of CeO2-Ni/Mo/SBA-15 Catalysts for Carbon Dioxide Reforming of Methane%CeO2/Ni/Mo/SBA-15甲烷二氧化碳重整催化剂的表征和催化性能

    Institute of Scientific and Technical Information of China (English)

    黄健; 马人熊; 高志华; 沈朝峰; 黄伟

    2012-01-01

    A Ni/Mo/SBA-15 catalyst was modified with CeO2 and compared with the unmodified catalyst.The catalysts were characterized by N2 adsorption,CO2 temperature-programmed desorption,H2 temperature-programmed reduction,Fourier transform infrared spectrometer,X-ray diffraction,scanning electron microscopy,and X-ray photoelectron spectroscopy.Both the Ni/Mo/SBA-15 and CeO2/Ni/Mo/SBA-15 catalysts gave good catalytic activities at atmospheric pressure.The CeO2 impregnated Ni/Mo/SBA-15 catalyst exhibited excellent stability at 800 ℃ for 100 h on stream,and after the resction,carbon deposits were not formed on the catalyst.The Ni/Mo/SBA-15 and CeO2/Ni/Mo/SBA-1 5 catalysts had a regular hexagonal mesoporous structure.The nickel species and the Ce-Mo oxide components were all in the SBA-15 mesopores.This prevented carbon deposition and sintering of the nickel species in the CeO2/Ni/Mo/SBA-15 catalyst.%考察了CeO2修饰及未修饰的Ni/Mo/SBA- 15催化剂在CH4-CO2重整上的催化性能并采用N2吸脱附、CO2程序升温脱附、H2程序升温还原、傅里叶红外光谱、X射线衍射、扫描电子显微镜和X射线光电子能谱对催化剂进行了表征.结果表明,在常压,800C条件下,经过100 h在线评价后,Ni/Mo/SBA- 15和CeOz/Ni/Mo/SBA- 15催化剂仍具有高的反应活性和规整的六方介孔结构,其中CeO2修饰的CeO2/Ni/Mo/SBA-15催化剂表面没有积炭形成,表明CeO2的加入促进了Ni物种在SBA-15介孔分子筛表面的分散,从而阻止了Ce/Ni/Mo/SBA- 15催化剂上Ni的烧结和积炭.

  11. 40CrNiMoA钢疲劳裂纹扩展速率免疫优化计算%Immune optimization algorithm for fatigue crack growth rate of 40CrNiMoA steel on tubine rotor

    Institute of Scientific and Technical Information of China (English)

    王钊; 马秀华; 刘娟丽; 李建兴; 陈荐

    2013-01-01

    基于Paris、Forman及Zheng-Hirt公式,建立了全程疲劳裂纹扩展速率的数学模型,利用免疫算法原理优化出影响汽轮机转子常用钢种40CrNiMoA的疲劳裂纹扩展速率和参数,优化结果符合试验规律,表明采用免疫算法处理多参数非线性疲劳裂纹扩展速率模型效果良好.

  12. Interface behavior study of WC92-Co8 coating produced by electrospark deposition

    Science.gov (United States)

    Ruijun, Wang; Yiyu, Qian; Jun, Liu

    2005-02-01

    WC92-Co8 coating produced by electrospark deposition effectively improves the surface performance of the substrate. The behavior of the interface between the WC92-Co8 coating and the substrate is studied in this paper. The high-melting-point WC92-Co8 was deposited onto the surface of Ti alloy, and the coating was usually more than 50 μm thick. The surface of the coating is mainly composed of TiC and W 2C besides a small amount of W, and its micro hardness reaches HV1129. The coating dramatically improves the performance of the substrate.

  13. Application of magnetron sputtering for producing bioactive ceramic coatings on implant materials

    Indian Academy of Sciences (India)

    J Z Shi; C Z Chen; H J Yu; S J Zhang

    2008-11-01

    Radio frequency (RF) magnetron sputtering is a versatile deposition technique that can produce thin, uniform, dense calcium phosphate coatings. In this paper, principle and character of magnetron sputtering is introduced, and development of the hydroxyapatite and its composite coatings application is reviewed. In addition, influence of heat treatment on magnetron sputtered coatings is discussed. The heat treated coatings have been shown to exhibit bioactive behaviour both in vivo and in vitro. At last, the future application of the bioactive ceramic coating deposited by magnetron sputtering is mentioned.

  14. Interface behavior study of WC92-Co8 coating produced by electrospark deposition

    Institute of Scientific and Technical Information of China (English)

    汪瑞军; 钱乙余; 刘军

    2004-01-01

    ESD (electrospark deposition) is a promising process to produce hard and wear-resisting coatings on metallic substrates. In this paper microstructure and interfacial characteristics of the WC92-Co8 coated on titanium and carbon steel are presented. A metallurgical bonding between the coating and substrate is obtained. The Ti element was found to distribute in WC92-Co8 at the metal pool, as well as the interface by diffusion. Some new phases were produced in the coating layer due to the chemical reaction during the ESD process. Experimental observation and thermodynamic analysis were utilized to study the mechanism of ESD.

  15. Effect of Chitosan on the Performance of NiMoP-Supported Catalysts for the Hydrodesulfurization of Dibenzothiophene

    Directory of Open Access Journals (Sweden)

    Guillermina Ríos-Caloch

    2016-01-01

    Full Text Available Chitosan-added NiMoP catalysts supported on alumina and alumina-titania were studied in the hydrodesulfurization (HDS of dibenzothiophene (DBT. The preparation of catalysts containing Mo (12 wt%, Ni (3 wt%, P (1.6 wt%, and chitosan/nickel = 2 (mol ratio was accomplished by sequential pore-filling impregnation varying the order of chitosan integration. Materials were characterized by DRIFTS, TPR, TG-DTA, and XPS techniques. The TG-DTA study showed that the nature of the support influences the degradation of chitosan onto the catalytic materials and also influences the HDS of DBT and the product distribution as well. The series of catalysts supported on alumina presented the most remarkable effect of chitosan, in which the OH and NH groups of the organic molecule interact with acid sites of the support weakening the interaction between alumina and deposited metal phases. In all cases, DBT was converted mainly through direct sulfur removal. The catalysts ChP3/A (alumina support impregnated with chitosan in phosphoric acid solution, prior to NiMoP deposition and ChP4/AT (alumina-titania support impregnated with NiMoP solution, prior to contacting with a solution comprising chitosan and phosphorus exhibited the best performance in HDS reactions and also showed the highest selectivity in biphenyl formation. Presence of carbonaceous residua on the catalyst’s surface, as shown by XPS, could enhance the HDS activity over the ChP4/AT sample.

  16. Performance Testing of Suspension Plasma Sprayed Thermal Barrier Coatings Produced with Varied Suspension Parameters

    Directory of Open Access Journals (Sweden)

    Nicholas Curry

    2015-07-01

    Full Text Available Suspension plasma spraying has become an emerging technology for the production of thermal barrier coatings for the gas turbine industry. Presently, though commercial systems for coating production are available, coatings remain in the development stage. Suitable suspension parameters for coating production remain an outstanding question and the influence of suspension properties on the final coatings is not well known. For this study, a number of suspensions were produced with varied solid loadings, powder size distributions and solvents. Suspensions were sprayed onto superalloy substrates coated with high velocity air fuel (HVAF -sprayed bond coats. Plasma spray parameters were selected to generate columnar structures based on previous experiments and were maintained at constant to discover the influence of the suspension behavior on coating microstructures. Testing of the produced thermal barrier coating (TBC systems has included thermal cyclic fatigue testing and thermal conductivity analysis. Pore size distribution has been characterized by mercury infiltration porosimetry. Results show a strong influence of suspension viscosity and surface tension on the microstructure of the produced coatings.

  17. Low content of Pt supported on Ni-MoCx/carbon black as a highly durable and active electrocatalyst for methanol oxidation, oxygen reduction and hydrogen evolution reactions in acidic condition

    Science.gov (United States)

    Zhang, Yan; Zang, Jianbing; Jia, Shaopei; Tian, Pengfei; Han, Chan; Wang, Yanhui

    2017-08-01

    Nickel and molybdenum carbide modified carbon black (Ni-MoCx/C) was synthesized by a two-step microwave-assisted deposition/carbonthermal reduction method and characterized by X-ray diffraction, transmission electron microscopy, energy dispersive spectroscopy and X-ray photoelectron spectroscopy. The as-prepared Ni-MoCx/C supported Pt (10 wt%) electrocatalyst (10Pt/Ni-MoCx/C) was synthesized through a microwave-assisted reduction method and 10Pt/Ni-MoCx/C exhibited high electrocatalytic activity for methanol oxidation, oxygen reduction and hydrogen evolution reactions. Results showed that 10Pt/Ni-MoCx/C electrocatalyst had better electrocatalytic activity and stability performance than 20 wt% Pt/C (20Pt/C) electrocatalyst. Among them, the electrochemical surface area of 10Pt/Ni-MoCx/C reached 68.4 m2 g-1, which was higher than that of 20Pt/C (63.2 m2 g-1). The enhanced stability and activity of 10Pt/Ni-MoCx/C electrocatalyst were attributed to: (1) an anchoring effect of Ni and MoCx formed during carbonthermal reduction process; (2) a synergistic effect among Pt, Ni, MoOx and MoCx. These findings indicated that 10Pt/Ni-MoCx/C was a promising electrocatalyst for direct methanol fuel cells.

  18. Behaviour of X5 CrNiMo 17-12-2 material during deep drawing process

    Directory of Open Access Journals (Sweden)

    M. Kršulja

    2012-04-01

    Full Text Available The subject of this paper is investigation of steel X5CrNiMo 17-12-2 in a deep drawing process. Material and mechanical properties are investigated in order to obtain a number of parameters that are needed for the deep drawing process. Tolerances for final product dimensions were taken and a procedure for deep drawing process was calculated. Tooling was modelled with Solidworks software. Experiments were performed in order to determine functionality of tooling, feasibility and influential factors on process uncertainties.

  19. Self-consistent (DFT + U) study of electronic, structural and magnetic properties in A2NiMoO6 (A = Ba, Sr) compounds

    Science.gov (United States)

    Aharbil, Y.; Labrim, H.; Benmokhtar, S.; Ait Haddouch, M.; Bahmad, L.; Laanab, L.

    2016-08-01

    This work aims to study the double perovskites A2NiMoO6 (A = Ba, Sr) by using the first principle calculation, within the framework of the self-consistent Hubbard correction. The value of this correction, for Ni and Mo depends strongly on the type of the studied compounds. Such values are determinate as 7.35 eV for Ni and 5.42 eV for Mo in the compound Ba2NiMoO6, whereas in the case of Sr2NiMoO6 the calculated values are 8.71 eV and 5.48 eV for Ni and Mo compound respectively. Based on the densities of state calculation we show that both the compounds are semiconductors with gap energies of 2.20 eV and 2.10 eV for Ba2NiMoO6 for Sr2NiMoO6, respectively. The total energies comparison shows clearly that the ground state is G-type anti-ferromagnetic order in agreement with experimental results, the magnetic interactions are due to the super-exchange mechanism acting in long range via hybridization throw Ni-O-Mo-O-Ni path.

  20. Support acidity influence in NiMoS (Nickel and Molybdenum) catalyst for Marlim diesel; Influencia da acidez do suport de catalisadores NiMoS (Niquel e Molibidenio) no hidrotratamento de diesel Marlim

    Energy Technology Data Exchange (ETDEWEB)

    Ferraz, Sheila Guimaraes de Almeida; Zotin, Jose Luiz; Jesus, Anderson Gomes de; Santos, Bruno Martins; Medeiros, Marcus Vinicius Costa [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2008-07-01

    The specification of diesel points to the reduction of the sulfur content, of the final boiling point, of the density range and increase of the cetane number. These two last properties are directly related with the ability of the hydrotreating catalytic system in promoting the hydrogenation of aromatic structures and ring opening of the naphthenic compounds, which are both associated to low cetane number. In such way, more acidic catalysts, able to promote the cracking of naphthenic structures, should be evaluated for the diesel HDT. Three bifunctional NiMo catalysts with the same metal content, different acidity and similar active phase dispersion were prepared using alumina, silica-alumina and alumina-Y zeolite as supports. These catalysts were evaluated in a micro-reactor unit for diesel HDT aiming to correlate their activity with the support acidity. The alumina and alumina-zeolite supported catalysts presented better performance than the one supported on silica-alumina. NiMo/alumina-zeolite showed higher cetane and density improvement, associated with a slight decrease in the initial boiling point. (author)

  1. 高强度钢30Cr3SiNiMoVA的疲劳特性研究%Study of Fatigue Performance for High Strength Steel 30Cr3SiNiMoVA

    Institute of Scientific and Technical Information of China (English)

    李斌; 董万元; 王小兵; 梁强

    2012-01-01

    In order to obtain fatigue design data of high strength steel 30Cr3SiNiMoVA, the fatigue test of this steel material have been carried out. In the experiment the material conditional fatigue limit was tested by the up-and-down method, and other fatigue data were done by the group test method under four stress levels for the polished specimen and unpolished specimen of the material, respectively. Then a two-parameter least square method was used to fit the S-N curve, and the probability method was used to obtain the PS-N curve. By the comparisons between two S-N curves, it is seen that the fatigue life of unpolished samples is lower than that of polished samples under same fatigue load level, so 30Cr3SiNiMoVA's fatigue life is sensitive to the surface rough state of the specimen, and this sensitivity is increasing with the decreasing of fatigue load, and the fatigue limit of the polished specimen is about 1. 4 times of the unpolished specimen. It is suggested that the effective technology should be applied into improving the surface rough state of one type of this material. These data will provided a valuable support for the engineering applications of 30Cr3SiNiMoVA.%为了获得超高强度钢30Cr3SiNiMoVA的疲劳设计数据,对该材料进行了疲劳性能实验.分别对该材料的抛光和未抛光试样进行轴向拉压疲劳实验.用升降试验法测定材料的条件疲劳极限,用成组实验法在四级应力水平下测试其疲劳寿命.结合升降法所得的条件疲劳极限值和成组法实验数据,采用双参数最小二乘法拟合SN曲线,运用概率方法求得P-S-N曲线.通过对两种试样的SN曲线分析可知:未抛光试样的疲劳寿命要低于抛光试样的疲劳寿命,并且疲劳载荷级越低,两类试样之间的疲劳寿命差越大,抛光试样的疲劳极限大约是未抛光试样的1.4倍.相关实验现象表明30Cr3SiNiMoVA的疲劳寿命对试样表面粗糙状态非常敏感,建议该类材料在应用过

  2. Production of bio-hydrogenated diesel by catalytic hydrotreating of palm oil over NiMoS2/γ-Al2O3 catalyst.

    Science.gov (United States)

    Srifa, Atthapon; Faungnawakij, Kajornsak; Itthibenchapong, Vorranutch; Viriya-Empikul, Nawin; Charinpanitkul, Tawatchai; Assabumrungrat, Suttichai

    2014-04-01

    Catalytic hydrotreating of palm oil (refined palm olein type) to produce bio-hydrogenated diesel (BHD) was carried out in a continuous-flow fixed-bed reactor over NiMoS2/γ-Al2O3 catalyst. Effects of dominant hydrotreating parameters: temperature: 270-420°C; H2 pressure: 15-80 bar; LHSV: 0.25-5.0 h(-1); and H2/oil ratio: 250-2000 N(cm(3)/cm(3)) on the conversion, product yield, and a contribution of hydrodeoxygenation (HDO) and decarbonylation/decarboxylation (DCO/DCO2) were investigated to find the optimal hydrotreating conditions. All calculations including product yield and the contribution of HDO and DCO/DCO2 were extremely estimated based on mole balance corresponding to the fatty acid composition in feed to fully understand deoxygenation behaviors at different conditions. These analyses demonstrated that HDO, DCO, and DCO2 reactions competitively occurred at each condition, and had different optimal and limiting conditions. The differences in the hydrotreating reactions, liquid product compositions, and gas product composition were also discussed.

  3. Hierarchical core-shell NiCo2O4@NiMoO4 nanowires grown on carbon cloth as integrated electrode for high-performance supercapacitors

    Science.gov (United States)

    Huang, Liang; Zhang, Wei; Xiang, Jinwei; Xu, Henghui; Li, Guolong; Huang, Yunhui

    2016-08-01

    Hierarchical core-shell NiCo2O4@NiMoO4 nanowires were grown on carbon cloth (CC@NiCo2O4@NiMoO4) by a two-step hydrothermal route to fabricate a flexible binder-free electrode. The prepared CC@NiCo2O4@NiMoO4 integrated electrode was directly used as an electrode for faradaic supercapacitor. It shows a high areal capacitance of 2.917 F cm‑2 at 2 mA cm‑2 and excellent cycling stability with 90.6% retention over 2000 cycles at a high current density of 20 mA cm‑2. The superior specific capacitance, rate and cycling performance can be ascribed to the fast transferring path for electrons and ions, synergic effect and the stability of the hierarchical core-shell structure.

  4. Hierarchical core-shell NiCo2O4@NiMoO4 nanowires grown on carbon cloth as integrated electrode for high-performance supercapacitors.

    Science.gov (United States)

    Huang, Liang; Zhang, Wei; Xiang, Jinwei; Xu, Henghui; Li, Guolong; Huang, Yunhui

    2016-01-01

    Hierarchical core-shell NiCo2O4@NiMoO4 nanowires were grown on carbon cloth (CC@NiCo2O4@NiMoO4) by a two-step hydrothermal route to fabricate a flexible binder-free electrode. The prepared CC@NiCo2O4@NiMoO4 integrated electrode was directly used as an electrode for faradaic supercapacitor. It shows a high areal capacitance of 2.917 F cm(-2) at 2 mA cm(-2) and excellent cycling stability with 90.6% retention over 2000 cycles at a high current density of 20 mA cm(-2). The superior specific capacitance, rate and cycling performance can be ascribed to the fast transferring path for electrons and ions, synergic effect and the stability of the hierarchical core-shell structure.

  5. Study to improve the quality of a Mexican straight run gasoil over NiMo/{gamma}-Al{sub 2}O{sub 3} catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Dominguez-Crespo, M.A. [Instituto Politecnico Nacional, Departamento de Metalurgia y Materiales, A.P. 75-876, 07300 Mexico D.F. (Mexico)]. E-mail: adcrespo2000@yahoo.com.mx; Diaz-Garcia, L. [Instituto Mexicano del Petroleo, Avenida Eje Central Lazaro Cardenas No. 152, Col. San Bartolo Atepehuacan, 07730 Mexico D.F. (Mexico); Arce-Estrada, E.M. [Instituto Politecnico Nacional, Departamento de Metalurgia y Materiales, A.P. 75-876, 07300 Mexico D.F. (Mexico); Torres-Huerta, A.M. [Instituto Politecnico Nacional, Departamento de Metalurgia y Materiales, A.P. 75-876, 07300 Mexico D.F. (Mexico); Cortez de la Paz, M.T. [Instituto Mexicano del Petroleo, Avenida Eje Central Lazaro Cardenas No. 152, Col. San Bartolo Atepehuacan, 07730 Mexico D.F. (Mexico)

    2006-11-30

    Four NiMo catalyst supported on Al{sub 2}O{sub 3} with different textural properties have been studied in the hydrodesulfurization (HDS), hydrodenitrogenation (HDN) and hydrodearomatization (HDA) of a Mexican straight run gasoil (SRGO). All reactions were carried out at three different temperatures 613, 633, and 653 K. Alumina supports were analysed by pyridine FTIR-TPD and nitrogen physisorption in order to determine their surface acidity and textural properties, respectively. TPR studies of the NiMo catalysts were analysed to correlate their hydrogenating properties. Metallic particles were characterized (after sulfidation) using transmission electron microscopy (TEM). Catalytic activities are discussed in relation to the physicochemical properties of NiMo catalysts. The importance of textural properties on coke deposition has been emphasized. The results of catalytic activity of these materials varied depending on dispersed MoS particles and pore distribution in final catalysts. The optimum pore diameter was found around 80 A for HDS and HDN.

  6. HIDRODENITROGENACION DE CARBAZOL SOBRE CATALIZADORES NiMo/Al2O3-SiO2(x

    Directory of Open Access Journals (Sweden)

    Felipe Sánchez-Minero

    2012-01-01

    Full Text Available En este trabajo se estudió la velocidad de reacción del carbazol sobre catalizadores NiMo soportados sobre Al2O3 modificada superficialmente con SiO2 (0 y 10 % en peso de SiO2 en el soporte. Los catalizadores fueron evaluados en un reactor intermitente a cuatro temperaturas (287, 300, 312 y 325oC, presión de 4.0 MPa y relación molar hidrogeno/carbazol de 2400. A partir de los resultados experimentales se realizó un estudio cinético utilizando ecuaciones del tipo Langmuir-Hinshelwood (L-H. Luego, los parámetros cinéticos fueron estimados mediante la minimización de Powell (programa Scientist de MicroMath. Los resultados muestran que el catalizador con sílice (NiMo-SAC 10 alcanza una mayor actividad para la HDN de carbazol debido a que presenta un mayor número de sitios activos (valor de A, así como una menor fuerza de adsorción entre el reactante y la superficie catalítica (valor de KN, lo cual posiblemente favorece una mejor regeneración de sitios activos.

  7. Iron-Based Amorphous Coatings Produced by HVOF Thermal Spray Processing-Coating Structure and Properties

    Energy Technology Data Exchange (ETDEWEB)

    Beardsley, M B

    2008-03-26

    The feasibility to coat large SNF/HLW containers with a structurally amorphous material (SAM) was demonstrated on sub-scale models fabricated from Type 316L stainless steel. The sub-scale model were coated with SAM 1651 material using kerosene high velocity oxygen fuel (HVOF) torch to thicknesses ranging from 1 mm to 2 mm. The process parameters such as standoff distance, oxygen flow, and kerosene flow, were optimized in order to improve the corrosion properties of the coatings. Testing in an electrochemical cell and long-term exposure to a salt spray environment were used to guide the selection of process parameters.

  8. MCrA1Y/TaC Metal Matrix Composite Coatings Produced by Electrospark Deposition

    Institute of Scientific and Technical Information of China (English)

    Yujiang XIE; Yanhong YANG; Mingsheng WANG; Jian HOU

    2013-01-01

    MCrAlY/TaC metal matrix composite coatings with 10,20 and 30 wt.% TaC have been successfully produced by electrospark deposition (ESD).The effects of TaC content on microstructure,hardness and oxidation behavior of the composite coatings were studied.The results showed that the composite coatings were composed of superfine γ columnar dendrite and large TaC particles dispersedly distributed.The hardness was enhanced but oxidation resistance of the composite coatings was reduced with increasing TaC contents.

  9. Re-Os isotopes and PGE geochemistry of black shales and intercalated Ni-Mo polymetallic sulfide bed from the Lower Cambrian Niutitang Formation, South China

    Institute of Scientific and Technical Information of China (English)

    JIANG Shaoyong; YANG Jinghong; LING Hongfei; FENG Hongzhen; CHEN Yongquan; CHEN Jianhua

    2003-01-01

    The Lower Cambrian Niutitang Formation consists of a thick black shale sequence with a regionally distributed conformable Ni-Mo polymetallic sulfide horizon and a chert bed at its basal strata on theYangtze Platform, South China. In this paper, we discuss all available data on Re-Os isotopes and Platinum Group Element (PGE) distribution pattern of the Ni-Mo polymetallic sulfide ore and its host rocks (black shales, cherts, and phosphorites) from Guizhou and Hunan provinces. Our results show that the black shales and the Ni-Mo sulfide ore have a high initial 187Os/188Os ratio of 0.78~0.86, indicating that the Early Cambrian ocean across the Yangtze Platform had a highly radiogenic Os value. This ratio is slightly lower than but still similar to present-day seawater, possibly as a result of high continental weathering at that time. The Ni-Mo sulfide ore yields a Re-Os isochron of 537±10 Ma (MSWD=11.9), possibly representing the depositional age of the Niutitang Formation. The chondrite-normalized PGE pattern, Pt anomaly (Pt/Pt*), Pt/Pd, Ir/Pd, Au/Ir and Re/Mo ratios of the Ni-Mo sulfide ore and its host rocks from South China indicate a varying source contribution of the PGE and other metals for different rocks. It is suggested that the cherts and Ni-Mo sulfide ore may have a significant proportion of PGE and probably other metals deriving from submarine-hydrothermal fluids with a mantle signature.

  10. Layer structured Na{sub 2}Ni(MoO{sub 4}){sub 2} particles as a visible-light-driven photocatalyst for degradation of methylene blue

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yuting; Chen, Luyang; Huang, Yanlin [College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123 (China); Chen, Cuili; Kim, Sun Il [Department of Physics and Interdisciplinary Program of Biomedical, Mechanical & Electrical Engineering, Pukyong National University, Busan 608-737 (Korea, Republic of); Seo, Hyo Jin, E-mail: hjseo@pknu.ac.kr [Department of Physics and Interdisciplinary Program of Biomedical, Mechanical & Electrical Engineering, Pukyong National University, Busan 608-737 (Korea, Republic of)

    2015-03-15

    Highlights: • Na{sub 2}Ni(MoO{sub 4}){sub 2} nanoparticles were developed by Pechini method. • The nanoparticles show high absorption in UV–vis wavelength region. • Na{sub 2}Ni(MoO{sub 4}){sub 2} has high activity in the MB dye degradation under visible light. • Hexagonal layers with heavily distorted NiO{sub 6} were superiority for photocatalysis. - Abstract: A new visible-light-driven photocatalyst of Na{sub 2}Ni(MoO{sub 4}){sub 2} particle was prepared by the modified Pechini method. The crystal structure was measured by X-ray diffraction (XRD) and the structural refinement. The sample was investigated by scanning electron microscope (SEM), transmission electron microscopy (TEM), and UV–vis absorption spectrum measurements. The average size of Na{sub 2}Ni(MoO{sub 4}){sub 2} particle is about 180 nm. Na{sub 2}Ni(MoO{sub 4}){sub 2} particle have an efficient optical absorption in the UV–visible light wavelength region with a direct allowed electronic transition of 2.06 eV. The effective photodegradation of methylene blue (MB) dye was demonstrated, which benefits from the special crystal structure of Na{sub 2}Ni(MoO{sub 4}){sub 2} particle. This crystal lattice has two infinite chains formed by (Ni,Na)O{sub 6} and MoO{sub 4} polyhedra standing in lines alone with the inner wall of the hexagonal tunnels. This results in the efficient optical absorption and provides more chances for electron–hole separations, which can further react with dye molecules to oxidize the dye pollutant into non-toxic products.

  11. Moisture resistant and anti-reflection optical coatings produced by plasma polymerization of organic compounds

    Science.gov (United States)

    Hollahan, J. R.; Wydeven, T.

    1975-01-01

    The need for protective coatings on critical optical surfaces, such as halide crystal windows or lenses used in spectroscopy, has long been recognized. It has been demonstrated that thin, one micron, organic coatings produced by polymerization of flourinated monomers in low temperature gas discharge (plasma) exhibit very high degrees of moisture resistence, e.g., hundreds of hours protection for cesium iodide vs. minutes before degradation sets in for untreated surfaces. The index of refraction of these coatings is intermediate between that of the halide substrate and air, a condition for anti-reflection, another desirable property of optical coatings. Thus, the organic coatings not only offer protection, but improved transmittance as well. The polymer coating is non-absorbing over the range 0.4 to 40 microns with an exception at 8.0 microns, the expected absorption for C-F bonds.

  12. Co-Pyrolysis Behaviors of the Cotton Straw/PP Mixtures and Catalysis Hydrodeoxygenation of Co-Pyrolysis Products over Ni-Mo/Al2O3 Catalyst

    Directory of Open Access Journals (Sweden)

    Derun Hua

    2015-12-01

    Full Text Available The doping of PP (polypropylene with cotton straw improved the bio-oil yield, which showed there was a synergy in the co-pyrolysis of the cotton straw and PP at the range of 380–480 °C. In a fixed-bed reactor, model compounds and co-pyrolysis products were used for reactants of hydrodeoxygenation (HDO over Ni-Mo/Al2O3. The deoxygenation rate of model compounds decreased over Ni-Mo/Al2O3 in the following order: alcohol > aldehyde > acetic acid > ethyl acetate. The upgraded oil mainly consisted of C11 alkane.

  13. Antimicrobial coatings for ensuring safety of fresh produces

    Science.gov (United States)

    Safety of fresh produce has been a perennial issue for the industry in the US despite tightening up regulations and implementing good manufacturing practice. The diversity of crops and labor-intense operations in the fresh produce production created a unique set of contamination routes that are not...

  14. In-situ TiC Reinforced Composite Coating Produced by Powder Feeding Laser Cladding

    Institute of Scientific and Technical Information of China (English)

    Sen YANG; Wenjin LIU; Minlin ZHONG

    2006-01-01

    A Ni-base alloy composite coating reinforced with TiC particles of various shapes and sizes on medium carbon steel substrate was produced by multilayer laser cladding. The chemical compositions, microstructures and surface morphology of the cladded layer were analyzed using energy dispersive X-ray spectroscopy (EDX),scanning electron microscope (SEM), and X-ray diffractometry (XRD). The experimental results showed that an excellent metallurgical bonding between the coating and the substrate was obtained. The microstructure of the coating was mainly composed of γ-Ni dendrites, a small amount of CrB, Ni3B, M23C6 and dispersed TiC particles. Much more and larger TiC particles formed in the overlapping zone, which led to a slightly higher microhardness of this zone. The maximum microhardness of the coating was about HV0.21200. The effects of the laser processing parameters on the microstructures and properties of coating were also investigated.

  15. Decreased Bacterial Attachment and Protein Adsorption to Coatings Produced by Low Enegy Plasma Polymerization

    DEFF Research Database (Denmark)

    Andersen, T.E.; Kingshott, Peter; Benter, M.

    with a surface less prone to the adsorption of biological matter. In the current study two different hydrophilic nanoscale coatings were produced by low energy plasma polymerization [3] and investigated· f()rl()w ... pr()tein adsorption and bacterial attachment properties. Methods were setup to enable...... and Methods: Coatings: Plasma polymerized poly(vinyl pyrrolidone) (PP-PVP), poly(2-methoxyethyl methacrylate) (PPPMEA) or an inorganic oxide (10) coating were applied onto medical grade silicon rubber sheets (Silopren LSR 2050, Momentive Performance Materials Inc.). Plasma polymerization chamber......-coated crystals were then treated with one of the plasma polymerized coatings. Adsorption of fibrinogen, human serum albumin or immunoglobulin G was measured using a QCM-D instrument [5] (model E4, Q-Sense AB, Vastra Frolunda, Sweden) using a solution of 50llg/1 protein in PBS buffer. Results and Discussion: Our...

  16. Strong third-order nonlinear response and optical limiting of α-NiMoO4 nanoparticles

    Science.gov (United States)

    Das, Amlan; Ratha, Satyajit; Yadav, Rajesh Kumar; Mondal, Anirban; Rout, Chandra Sekhar; Adarsh, K. V.

    2017-07-01

    In this manuscript, we demonstrate the strong resonant two photon absorption coefficient ≈71 ± 5 cm/GW at 532 nm in α-NiMoO4 nanoparticles prepared by a facile hydrothermal method. Strikingly, we have obtained the optical limiting onset threshold fluence (FON) of 36 mJ/cm2 for the linear transmittance of 0.64 with an excellent two photon absorption cross section (38 × 10-45 cm4 s), which suggests that they can be utilized as passive optical limiters. To explain the observed effects, we present a two-level rate equation model and numerically simulated the Z-scan peak shape, which is in good agreement with the experimental data. Further, we also show the normalized population density of the carriers in excited and ground states.

  17. Residue Upgrading in Slurry Phase over Ultra-ifne NiMo/γ-Al2O3 Catalyst

    Institute of Scientific and Technical Information of China (English)

    Tong Fengya; Yang Qinghe; Li Dadong; Dai Lishun; Deng Zhonghuo

    2015-01-01

    In this article, residual oil hydroconversion was studied in slurry phase in the presence of ifne solid NiMo/γ-Al2O3 catalyst and the effects of operating conditions were carefully studied. The results showed that residue conversion was only affected by the reaction temperature and reaction time. The coke yield increased with a higher reaction temperature, a bigger catalyst particle size, a longer reaction time, a lower initial hydrogen pressure and a lower catalyst concentration. Hetero-atoms removal rate increased with a higher reaction temperature, a longer reaction time, a higher initial hydrogen pressure, a higher catalyst concentration, and a smaller catalyst particle size. The role of catalyst in the slurry bed technology was discussed and its function could be stated as follows:the metal was applied to activate the hydrogen atoms for removing heteroatoms and saturating aromatics, while the support of the catalyst was used to prevent the mesophase coalescence for reducing coke formation.

  18. Possibility of utilizing water-atomized Fe-Ni-Mo steel powder as base materials for warm compaction process

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Water-atomized Fe-Ni-Mo steel powder, was utilized as base powder for designing powder mixtures for warm pressing The warm pressing and sintering behaviours of the powder mixtures were studied. The results show that, compared with the pressing at room temperature, the green density gain by warm pressing is within a range of 0.10-0.19 g/cm3 and reduction in spring back is 30%-40% of the ambient, and maximum green density of 7.32 g′cm3 at 735 MPa is obtained as the graphite mass fraction is 0.8%. It was found than sintered densities of the compacts were reduced slightly due to releasing of elastic stress stored in the compacts during sintering. The warm pressing of steel powders gives evidence for substituting the traditional double pressing and double sintering process.

  19. Hydrodesulfurization and Hydrodenitrogenation Kinetics of a Heavy Gas Oil over NiMo/Al2O3 Catalysts

    Institute of Scientific and Technical Information of China (English)

    DUAN Ai-jun; XU Chun-ming; LIN Shi-xiong; CHUNG Keng H

    2005-01-01

    The kinetics of Athabasca bitumen derived heavy gas oil over NiMo/Al2O3 catalysts were studied in a JQ-II high-pressure microscale hydrotreator unit under different operation conditions, including temperature, pressure, H/O ratio and LHSV. The multi-parameter models of hydrodesulfurization and hydrodenitrogenation were proposed. The model parameters verify that the HDS and HDN reactions follow 1.5-order and 1.6-order kinetic rules, respectively. The kinetic activation energies of HDN and HDS over Com, Hom1 and Hom2 show that homemade catalysts exhibit higher activities in HDN than commercial catalyst. Using the multi-parameter kinetic model to predict the contents of sulfur and nitrogen in products is in good agreement with the experimental data.

  20. Effect of phosphorus on the hydrodesulfurization and hydrodenitrogenation performance of presulfided NiMo/Al2O3 catalyst%磷对预硫化型NiMo/Al2O3催化剂加氢脱硫脱氮性能的影响

    Institute of Scientific and Technical Information of China (English)

    相春娥; 柴永明; 樊晶; 刘晨光

    2011-01-01

    利用等体积浸渍法制备了不同磷含量的预硫化型NiMo/Al2O3催化剂,并利用XRD、BET、TPR和HRTEM等分析方法对其进行了表征,研究了磷对其加氢脱硫脱氮性能的影响.结果表明,由于预硫化型NiMo加氢催化剂上活性组分和载体的相互作用较弱,MoS2或Ni-Mo-S相主要以TypeⅡ形式存在,磷通过增加MoS2的堆积层数、减小片晶长度提高了MoS2的分散度.TPR结果表明磷仅提高了金属硫化物中Ni-Mo-S相的比例,而对Ni-Mo-S相和体相MoS2中的金属-硫键的键合强度没有影响.NiMoP-1.2催化剂(磷负载量为1.2%)表面MoS2的分散度最高,同时也具有最高的加氢脱硫(HDS)选择性和加氢脱氮(HDN)活性;过高磷含量(NiMoP-1.8,磷负载量为1.8%)则造成MoS2分散度降低,催化剂的比表面积、孔径和孔容也减小,导致其HDS和HDN反应性能下降.%Phosphorus promoted presulfided NiMo/A12 O3 catalysts were prepared by successive incipient wemess impregnation and characterized by XRD, N2-physisorption, TPR and HRTEM. The effect of phosphorus on the hydrodesulfurization ( HDS ) hydrodenitrogenation (HDN) performance of the presulfided NiMo/Al203 catalyst was investigated. The results indicate that the main active phase is type Ⅱ MoS2 or Ni-Mo-S phase because of theft weak interaction with the support. The incorporation of phosphorus in the catalyst enhances the dispersion of MoS2 particles by increasing the stacking number and reducing the slab length.Phosphorus has no influence on the metal-sulfur bonding energies in the Ni-Mo-S phases and bulk MoS2, but it increases the proportion of Ni-Mo-S phases in the metal sulfides. NiMoP-1.2 catalyst ( containing 1.2% phosphoms) exhibits high hydrogenation (HYD) selectivity in the HDS of dibenzothiophene (DBT) and high HDN ratio of quinoline, which can be attributed to its high dispersion of the active phase. The HYD activity in HDS and HDN ratio on NiMoP-1.8 catalyst with excess phosphorus ( 1.8

  1. Microstructural, mechanical and oxidation features of NiCoCrAlY coating produced by plasma activated EB-PVD

    Energy Technology Data Exchange (ETDEWEB)

    He, Jian; Guo, Hongbo, E-mail: guo.hongbo@buaa.edu.cn; Peng, Hui; Gong, Shengkai

    2013-06-01

    NiCoCrAlY coatings produced by electron beam-physical vapor deposition (EB-PVD) have been extensively used as the oxidation resistance coatings or suitable bond coats in thermal barrier coating (TBC) system. However, the inherent imperfections caused by EB-PVD process degrade the oxidation resistance of the coatings. In the present work, NiCoCrAlY coatings were creatively produced by plasma activated electron beam-physical vapor deposition (PA EB-PVD). The novel coatings showed a terraced substructure on the surface of each grain due to the increased energy of metal ions and enhanced mobility of adatoms. Also a strong (1 1 1) crystallographic texture of γ/γ′ grains was observed. The toughness of the coatings got remarkably improved compared with the coatings deposited by conventional EB-PVD and the oxidation behavior at 1373 K showed that the novel coatings had excellent oxidation resistance. The possible mechanism was finally discussed.

  2. Experimental modeling of polymer latex spray coating for producing controlled-release urea

    Institute of Scientific and Technical Information of China (English)

    Rui Lan; Yonghui Liu; Guanda Wang; Tingjie Wang; Chengyou Kan; Yong Jin

    2011-01-01

    Spray coating of polymer latex onto fertilizer particles in a fluidized bed for producing controlled-release urea is an environment friendly technology as it does not need any toxic organic solvent.Since the spray coating process in a fluidized bed occurs in the presence of particle collisions,the coating of the particles is random,intermittent and multiple,thus making it difficult to investigate the film formation process.In this paper,an experimental model apparatus was designed and used to investigate the effects of the key factors in the spray coating process.This apparatus reasonably simplified the complex process to avoid particle collisions and randomness in the coating.The intermittent coating in the fluidized bed was modeled by periodic coating and dewatering in the experimental apparatus.A large area film was obtained,and the film permeability was measured.The effects of atomizing gas flow rate,spray rate of latex,solid content of latex and gas temperature on film structure and film permeability were investigated.It was found that water transfer played a dominant role in the spray coating process.

  3. Characterization of Vc-Vb Particles Reinforced Fe-Based Composite Coatings Produced by Laser Cladding

    Science.gov (United States)

    Qu, K. L.; Wang, X. H.; Wang, Z. K.

    2016-03-01

    In situ synthesized VC-VB particles reinforced Fe-based composite coatings were produced by laser beam melting mixture of ferrovanadium (Fe-V) alloy, boron carbide (B4C), CaF2 and Fe-based self-melting powders. The results showed that VB particles with black regular and irregular blocky shape and VC with black flower-like shape were uniformly distributed in the coatings. The type, amount, and size of the reinforcements were influenced by the content of FeV40 and B4C powders. Compared to the substrate, the hardness and wear resistance of the composite coatings were greatly improved.

  4. Conversion Coatings Produced on AZ61 Magnesium Alloy by Low-Voltage Process

    Directory of Open Access Journals (Sweden)

    Nowak M.

    2016-03-01

    Full Text Available The resultes of anodic oxide conversion coatings on wrought AZ61 magnesium alloy production are describe. The studies were conducted in a solution containing: KOH (80 g/l and KF (300 g/l using anodic current densities of 3, 5 and 10 A/dm2 and different process durations. The obtained coatings were examined under a microscope and corrosion tests were performed by electrochemical method. Based on these results, it was found that the low-voltage process produces coatings conferring improved corrosion resistance to the tested magnesium alloy.

  5. FEM ANALYSIS OF THERMAL STRESSES IN GRADIENT THERMAL BARRIER COATINGS PRODUCED BY EB-PVD

    Institute of Scientific and Technical Information of China (English)

    H.B. Guo; H.B. Xu; S.K. Gong

    2001-01-01

    Gradient thermal barrier coatings (GTBCs) produced by co-deposition of mixtures ofAl-Al2 O3-YSZ onto metallic bond coat exhibited longer lifetimes than the two-layeredTBCs. The finite element method (FEM) numerical models were used to investigatestress and strain states in the GTBCs and traditional two-layered TBCs as they cooledto 750℃ from a stress-free state at 850℃.

  6. Toxicity of hydrogen peroxide produced by electroplated coatings to pathogenic bacteria.

    Science.gov (United States)

    Zhao, Z H; Sakagami, Y; Osaka, T

    1998-05-01

    The ability of various electroplated coatings (cobalt, zinc, copper, and cobalt-containing alloys of nickel, zinc, chromium, etc.) to inhibit the growth of pathogenic bacteria (Gram-positive bacteria Enterococcus faecalis and methicillin-resistant Staphylococcus aureus and Gram-negative bacteria Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae) was determined by a drop-method antibacterial experiment. The amounts of H2O2 produced and metal ions dissolved from the surfaces of various electroplated coatings were measured and it was found that the inhibitory ability of coatings corresponded to the amounts of H2O2 produced. The more significant the inhibition of the coating to bacterial growth, the greater the amount of H2O2 production. In addition, the bacterial survival rates on the surfaces of coatings were almost zero when H2O2 was produced in amounts greater than 10(-6) mmol/cm2. However, the dominant concentrations of metal ions dissolved from coatings were outside of the bacterial lethal range.

  7. MoS2 PARTICLES MODIFIED WITH POLYSTYRENE FOR PRODUCING Ni–PS/MoS2 COATINGS

    OpenAIRE

    ZHONGJIA HUANG; DANGSHENG XIONG

    2008-01-01

    The MoS2 particles were coated with polystyrene and can be written as PS/MoS2 hereinafter. Ni–PS/MoS2 coatings and Ni–MoS2 coatings were produced by PC electrodeposition technique. The surface morphology of Ni–PS/MoS2 coating was examined and compared with those of Ni–MoS2 coating. The effect of particle concentrations on the volume percent of particles incorporated in the coatings was investigated. And the microhardness of coatings was also investigated. Results show that the surface morphol...

  8. Surface morphology and electrochemical characterization of electrodeposited Ni Mo nanocomposites as cathodes for hydrogen evolution

    Institute of Scientific and Technical Information of China (English)

    Elhachmi Guettaf Temam; Hachemi Ben Temam; Said Benramache

    2015-01-01

    In this work, we study the infl uences of current density on surface morphology and electrochemical characterization of electrodeposited Ni–Mo. The Ni–Mo composite coatings are deposited on pretreated copper substrates by electrolytic deposition. The Ni–Mo solution is taken from nickel sulfate fl uid and ammonium heptamolybdate with 10 g/l. The Ni–Mo composite coatings are deposited at a temperature of 303 K with an applied current density of jdep=10 A/dm2–30 A/dm2. We find that the corrosion resistance is improved by incorporating Mo particles into Ni matrix in 0.6-M NaCl solution. From the potentiodynamic polarization curve of electrodeposited Ni–Mo it is confirmed that the corrosion resistance decreases with increasing applied current density. The x-ray diffraction (XRD) analyses of Ni–Mo coatings indicate three phases of MoNi4, Mo1.24Ni0.76, and Ni3Mo phases crystallites of nickel and molybdenum. The scanning electronic microscopy (SEM) tests indicate that Ni–Mo coatings present cracks and pores.

  9. Characterization of Fe-Cr-B based coatings produced by HVOF and PTA processes

    Science.gov (United States)

    Kim, Hyung-Jun; Grossi, Stephanie; Kweon, Young-Gak

    1999-02-01

    Two Fe-Cr-B based gas atomized powders, Armacor M and 16, were thermally sprayed on a low carbon steel substrate, using the HVOF (High Velocity Oxygen Fuel) process. Armacor M was also weld-surfaced with the PTA (Plasma Transferred Arc) process. The resultant deposits were subsequently characterized, using X-ray diffraction, scanning electron microscopy, and microhardness measurement. The effects of heat treatment were also studied for HVOF-sprayed coatings. The wear performance of the coatings was investigated by two-body abrasive wear tests. The results of microstructural analysis of as-sprayed deposits revealed oxide and boride phases such as Fe3O4 and Cr1.65F0.35B0.96 in an α matrix for the HVOF-sprayed Armacor 16 coating, and only the boride phases (Cr1.65F0.35B0.96 and Cr2B) in an α matrix for the HVOFsprayed Armacor M coating. PTA weld-surfaced Armacor M coating contains needle-type long precipitates of Cr2B) and Cr1.65F0.35B0.96, in the α matrix. The hardness of the HVOF-sprayed Armacor 16 coating after heat treatment was substantially less than that of the as-sprayed coating due to the phase transformation from α to γ phase. Heat treatments of the HVOF-sprayed Armacor M coating did not produce changes in phase and its hardness decreased as compared to that of the as-sprayed coating. While HVOF-sprayed and PTA weld-surfaced Armacor M coatings have the same hardness, the latter shows better abrasive wear resistance because of the size and orientation of its boride phases. The broadening of the XRD patterns and the increase in hardness after wear testing suggest that the transformation from the crystalline to the amorphous structure occurred on the uppermost layer during wear testing.

  10. Novel Alkyd-Type Coating Resins Produced Using Cationic Polymerization [PowerPoint

    Energy Technology Data Exchange (ETDEWEB)

    Chisholm, Bret; Kalita, Harjyoti; Alam, Samim; Jayasooriyamu, Anurad; Fernando, Shashi; Samanata, Satyabrata; Bahr, James; Selvakumar, Sermadurai; Sibi, Mukund; Vold, Jessica; Ulven, Chad

    2014-04-07

    Novel, partially bio-based poly(vinyl ether) copolymers derived from soybean oil and cyclohexyl vinyl ether (CHVE) were produced by cationic polymerization and investigated for application as alkyd-type surface coatings. Compared to conventional alkyd resins, which are produced by high temperature melt condensation polymerization, the poly(vinyl ether)s provide several advantages. These advantages include miler, more energy efficient polymer synthesis, elimination of issues associated with gelation during polymer synthesis, production of polymers with well-defined composition and relatively narrow molecular weight distribution, and elimination of film formation and physical property issues associated with entrained monomers, dimers, trimmers, etc. The results of the studied showed that the thermal, mechanical, and physical properties of the coatings produced from these novel polymers varied considerable as a function of polymer composition and cure temperature. Overall, the results suggest a good potential for these novel copolymers to be used for coatings cured by autoxidation.

  11. Osteoblast proliferation on hydroxyapatite thin coatings produced by right angle magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Mello, A [Instituto Militar de Engenharia, IME, Rio de Janeiro, 22290-270, RJ (Brazil); Hong, Z [Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States); Rossi, A M [Centro Brasileiro de Pesquisas FIsicas, Rua Dr. Xavier Sigaud, 150, Rio de Janeiro, 22290-180, RJ (Brazil); Luan, L [Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States); Farina, M [Instituto de Ciencias Biomedicas, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Rio de Janeiro, RJ, 21941-590 (Brazil); Querido, W [Instituto de Ciencias Biomedicas, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Rio de Janeiro, RJ, 21941-590 (Brazil); Eon, J [Inst. QuImica, PUC/RJ, Rio de Janeiro, 21941-590, RJ (Brazil); Terra, J [Centro Brasileiro de Pesquisas FIsicas, Rua Dr. Xavier Sigaud, 150, Rio de Janeiro, 22290-180, RJ (Brazil); Balasundaram, G [Division of Engineering, Brown University, Providence, RI, 02912 (United States); Webster, T [Division of Engineering, Brown University, Providence, RI, 02912 (United States); Feinerman, A [Department of Electrical and Computer Engineering, University of Illinois, Chicago, IL, 60612 (United States); Ellis, D E [Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States); Ketterson, J B [Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States); Ferreira, C L [Instituto Militar de Engenharia, IME, Rio de Janeiro, 22290-270, RJ (Brazil)

    2007-06-01

    Right angle magnetron sputtering (RAMS) was used to produce hydroxyapatite (HA) film coatings on pure titanium substrates and oriented silicon wafer (Si(0 0 1)) substrates with flat surfaces as well as engineered surfaces having different forms. Analyses using synchrotron XRD, AFM, XPS, FTIR and SEM with EDS showed that as-sputtered thin coatings consist of highly crystalline hydroxyapatite. The HA coatings induced calcium phosphate precipitation when immersed in simulated body fluid, suggesting in vivo bioactive behavior. In vitro experiments, using murine osteoblasts, showed that cells rapidly adhere, spread and proliferate over the thin coating surface, while simultaneously generating strong in-plane stresses, as observed on SEM images. Human osteoblasts were seeded at a density of 2500 cells cm{sup -2} on silicon and titanium HA coated substrates by RAMS. Uncoated glass was used as a reference substrate for further counting of cells. The highest proliferation of human osteoblasts was achieved on HA RAMS-coated titanium substrates. These experiments demonstrate that RAMS is a promising coating technique for biomedical applications.

  12. OXIDATION RESISTANCE OF NANOCRYSTAL ODS ALUMINIDE COATINGS PRODUCED BY PACK ALUMINIZING PROCESS ASSISTED BY BALL PEENING

    Institute of Scientific and Technical Information of China (English)

    Z.L. Zhan; Y.D. He; W. Gao

    2006-01-01

    Nanocrystal ODS (oxide dispersion strengthening) aluminide coatings were produced on a stainless steel and nickel-based superalloy by the pack aluminizing process assisted by ball peening. Pure Al powders and 1% of ultra-fine Y2O3 powders were mixed by ball milling. The ultra-fine Y2O3powders were dispersed in Al particles. Ball peening welded the Al particles onto the substrate and accelerated the formation of aluminide coating. Nanocrystal ODS aluminide coatings were produced by the outward growth at a much low temperature (below 600℃) in a short treatment time.The effects of the operation temperature and treatment time on the formation of the coatings were analyzed. SEM (scanning electron microscope), AFM (atomic force microscope), EDS (energy dispersive X-ray spectroscopy), XRF (X-ray fluorescence spectrometer) and XRD (X-ray diffraction )methods were applied to investigate the microstructure of the coatings. High-temperature oxidation tests were carried out to evaluate the oxidation resistance of the ODS aluminide coatings.

  13. Preparation of (Ni-Mo)-TiO2 thin films and their photocatalytic activity of Rhodamine B%(Ni-Mo)-TiO2纳米薄膜的制备及其光催化降解罗丹明B的性能

    Institute of Scientific and Technical Information of China (English)

    李爱昌; 赵娣; 李倩; 张敬; 郑彦俊

    2012-01-01

    以恒电流复合电沉积方法制备(Ni-Mo)-TiO2薄膜.采用SEM、XRD和DRS对薄膜的表面形貌、相结构和光谱特性进行表征,以罗丹明B为模拟污染物对薄膜的光催化活性进行测定,讨论罗丹明B溶液的pH值、通入气体以及不同辐射光波对薄膜光催化性能的影响,并推测光催化机理.结果表明:(Ni-Mo)-TiO2薄膜是由TiO2纳米粒子相和纳米晶Ni-Mo固溶体相构成的复合薄膜.薄膜具有较高的光催化活性,在可见光和紫外光照射下,罗丹明B的降解率分别为多孔P25 TiO2粒子薄膜的2.0倍和1.7倍.复合薄膜光催化活性的提高主要源于在薄膜层中能有效形成(Ni-Mo)/TiO2异质结和良好的电子通道,它一方面可以促使光生电荷的分离,另一方面加速了氧气与激发电子的还原反应.%The (Ni-Mo)-TiO2 thin film was prepared by electrolytic co-deposition of Ni-Mo ally and TiO2 particles from a solution in which TiO2 nano particles (P25) were suspended by stirring. The surface morphology, phase structure and optical characteristics of the thin film were analyzed by scanning electron microscopy (SEM), X-ray diffractometry (XRD) and diffuse reflectance ultraviolet-visible spectroscopy (DRS), respectively. The photocatalytic properties were evaluated with Rhodamine B as a model compound. The effects of pH of the Rhodamine B aqueous solution, gaes bubbling through the solution, UV and visible light irradiation on the photocatalytic activity of (Ni-Mo)-TiO2 thin film were investigated. And the photocatalytic reaction mechanism was presumed. The results show that the (Ni-Mo)-TiO2 thin film consists of TiO2 crystalline particles in the size of 50-100nm and Ni-Mo nano crystalline in solid solution. The (Ni-Mo)-TiO2 film is photocatalytically more active than that of TiO2/ITO. Under visible and UV light irradiation, the photocatalytic degradation rate of (Ni-Mo)-TiO2 film is 2.0 times and 1.7 times as much as that of the TiCVTK) thin film

  14. Microstructure of Welded Joint for X60 Steel Welded with ECrNiMo-3%ECrNiMo-3焊接X60钢接头组织形貌

    Institute of Scientific and Technical Information of China (English)

    杨丽颖; 董小平; 李小亭; 柳伟; 路民旭

    2009-01-01

    利用扫描电镜(SEM)、透射电镜(TEM)观察镍基合金焊缝/X60钢焊接接头微观组织,能谱分析(EDS)测试Cr,Ni,Mo,Fe合金元素在各区域分布,并通过计算获得Mn,C在部分熔化区含量.结果表明:完全混合区为树枝状奥氏体组织,Mo偏析到枝晶间隙.不完全混合区是平面晶形貌,未出现偏析现象,宽度约30μm,在该区内从熔合线到完全混合区,Cr,Ni,Mo含量逐渐增加,X60钢母材Fe含量逐渐降低.部分熔化区是由马氏体基体上镶嵌着大量的第二相粒子构成,仅200nm宽.

  15. Application of new analytical techniques to the order-disorder transformation in Ni-Mo alloys; Ni-Mo gokin no kisoku-fukisoku hentai ni okeru atarashii kozo kaiseki no kokoromi

    Energy Technology Data Exchange (ETDEWEB)

    Oki, K.; Hata, S.; Kuwano, N. [Kyushu University, Fukuoka (Japan)

    1997-09-20

    This paper presents the analytical example of the ordering process of order-disorder transformation in Ni-Mo alloy using recent experimental techniques. Monte Carlo simulation clarified the fact that the ordering process in Ni4-Mo alloy is largely affected by short range interaction in the early stage of ordering, and forms D1a, D022 and Pt2Mo structure units with a similar atomic pair correlation. The ordering process is largely affected by long range interaction with an advance of ordering, and develops only D1a structure most stable in energy. In order to check the existence of SRO (short range order) structure obtained by Monte Carlo simulation, the analysis of high-resolution TEM images under SRO condition was carried out using the imaging plate recently developed for TEM. The analytical result showed that the observed N2M3 pattern is derived from not always the existence of N2M3 structure but superimposition of D1a, D022 and Pt2Mo structure units. 19 refs., 4 figs.

  16. Effects of Heat Treatment and Nitrogen on Microstructure and Mechanical Properties of 1Cr12NiMo Martensitic Stainless Steel

    Institute of Scientific and Technical Information of China (English)

    Ruicheng Fan; Ming Gao; Yingche Ma; Xiangdong Zha; Xianchao Hao; Kui Liu

    2012-01-01

    A series of heat treatments using the orthogonal experiment method were performed to study the microstruc- ture and mechanical properties of 1Cr12NiMo martensitic stainless steel containing various nitrogen content addition. The results indicate that the optimal heat treatment is annealing at 830 ℃ for 1 h, austenitizing at 985 ℃ for 1 h followed by oil quenching, and tempering at 630 ℃ for 4 h followed by air cooling, Nitrogen addition to 1Cr12NiMo steel can effectively hinder the austenite grain growth, refine the martensite lath, and increase the strength and hardness. The impact toughness of this steel only shows a minor decrease as the nitrogen content increases.

  17. Synthesis, characterization and electrochemical performance of graphene decorated with 1D NiMoO4.nH2O nanorods

    Science.gov (United States)

    Ghosh, Debasis; Giri, Soumen; Das, Chapal Kumar

    2013-10-01

    One-dimensional NiMoO4.nH2O nanorods and their graphene based hybrid composite with good electrochemical properties have been synthesized by a cost effective hydrothermal procedure. The formation of the mixed metal oxide and the composite was confirmed by XRD, XPS and Raman analyses. The morphological characterizations were carried out using FESEM and TEM analyses. The materials were subjected to electrochemical characterization through cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) studies with 6 M KOH as the supporting electrolyte. For NiMoO4.nH2O, a maximum specific capacitance of 161 F g-1 was obtained at 5 A g-1 current density, accompanied with an energy density of 4.53 W h kg-1 at a steady power delivery rate of 1125 W kg-1. The high utility of the pseudocapacitive NiMoO4.nH2O was achieved in its graphene based composite, which exhibited a high specific capacitance of 367 F g-1 at 5 A g-1 current density and a high energy density of 10.32 W h kg-1 at a power density of 1125 W kg-1 accompanied with long term cyclic stability.One-dimensional NiMoO4.nH2O nanorods and their graphene based hybrid composite with good electrochemical properties have been synthesized by a cost effective hydrothermal procedure. The formation of the mixed metal oxide and the composite was confirmed by XRD, XPS and Raman analyses. The morphological characterizations were carried out using FESEM and TEM analyses. The materials were subjected to electrochemical characterization through cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) studies with 6 M KOH as the supporting electrolyte. For NiMoO4.nH2O, a maximum specific capacitance of 161 F g-1 was obtained at 5 A g-1 current density, accompanied with an energy density of 4.53 W h kg-1 at a steady power delivery rate of 1125 W kg-1. The high utility of the pseudocapacitive NiMoO4.nH2O was achieved in its graphene

  18. Effect of La2O3 on Methanation of CO and CO2 over Ni-Mo/γ-Al2O3 Catalyst

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A series of Ni-Mo/γ-Al2O3 methanation catalysts containing La2O3 were prepared by impregnation. The activities of catalysts for CO and CO2 methanation were investigated. The surface properties of the catalysts were studied by TEM, XPS and chemisorption of CO. The experimental results show that the addition of La2O3 increases the activities for the methanation of CO and CO2, the dispersity of nickel on catalysts, the active nickel surface area and the concentration of nickel atoms on the surface of Ni-Mo/γ-Al2O3 catalysts. At the same time, it also decreases the binding energy of Ni2P3/2 in catalysts.

  19. Al-pillared montmorillonite-based NiMo catalysts for HDS and HDN of gas oil. Influence of the method and order of Mo and Ni impregnation

    Energy Technology Data Exchange (ETDEWEB)

    Salerno, P.; Mendioroz, S.; Lopez Agudo, A. [Instituto de Catalisis y Petroleoquimica CSIC, Camino de Valdelatas, s/n. Campus Universidad Autonoma de Madrid, 28049 Cantoblanco, Madrid (Spain)

    2004-03-08

    The effect of the impregnation method (co-impregnation and sequential) and the incorporation order of the active phases, Ni and Mo, on the structure and catalytic activity of NiMo hydrotreating catalysts supported on an Al-pillared montmorillonite has been investigated. The catalysts were characterised by X-ray diffraction, N{sub 2} adsorption, thermogravimetric analysis, temperature-programmed reduction, UV-Vis diffuse reflectance, in situ laser Raman, and X-ray photoelectron spectroscopies, and their catalytic behaviour tested in the hydrodesulphurisation (HDS) and hydrodenitrogenation (HDN) of gas oil. It was found that the catalyst prepared by co-impregnation of Ni and Mo was more active than those prepared by sequential impregnation, and of the latter ones, the most active was that in which Mo was impregnated prior to Ni. Characterisation results revealed that by co-impregnation, the dispersion of the Mo phase was significantly increased due to the presence of Ni and, on the other hand, more Ni stay together to Mo on the external surface of the clay, favouring thus the formation of Ni-Mo-O interaction species, precursors of the 'Ni-Mo-S' active phase. The relatively low activity of the sequentially impregnated Mo-Ni/Al-PILC catalyst was due to the absence of synergism between Ni and Mo because most of Ni was as Ni{sup 2+} ions into the octahedral layers of the clay, separated from the Mo phase. All NiMo bimetallic catalysts exhibited initially a better selectivity towards HDN than towards HDS reaction, probably due to their acidity properties.

  20. Experimental and Thermodynamic Study of Selected in-Situ Composites from the Fe-Cr-Ni-Mo-C System

    Directory of Open Access Journals (Sweden)

    Wieczerzak K.

    2016-06-01

    Full Text Available The aim of the study was to synthesize and characterize the selected in-situ composites from the Fe-Cr-Ni-Mo-C system, additionally strengthened by intermetallic compounds. The project of the alloys was supported by thermodynamic simulations using Calculation of Phase Diagram approach via Thermo-Calc. Selected alloys were synthesized in an arc furnace in a high purity argon atmosphere using a suction casting unit. The studies involved a range of experimental techniques to characterize the alloys in the as-cast state, including optical emission spectrometry, light microscopy, scanning electron microscopy, electron microprobe analysis, X-ray diffraction and microhardness tests. These experimental studies were compared with the Thermo-Calc data and high resolution dilatometry. The results of investigations presented in this paper showed that there is a possibility to introduce intermetallic compounds, such as χ and σ, through modification of the chemical composition of the alloy with respect to Nieq and Creq. It was found that the place of intermetallic compounds precipitation strongly depends on matrix nature. Results presented in this paper may be successfully used to build a systematic knowledge about the group of alloys with a high volume fraction of complex carbides, and high physicochemical properties, additionally strengthened by intermetallic compounds.

  1. Structural and electrical characterizations of cerium (Ce3+)-doped double perovskite system Sr2NiMoO6- δ

    Science.gov (United States)

    Kumar, Pravin; Singh, Nitish Kumar; Sinha, A. S. K.; Singh, Prabhakar

    2016-09-01

    The double perovskite system Sr2- x Ce x NiMoO6- δ (SCNM) with 0.01 ≤ x ≤ 0.05 was synthesized by the citrate-nitrate auto-combustion synthesis route. Thermal studies were carried out by simultaneous differential scanning calorimetry and thermal gravimetry. Phase constitution was analyzed by powder X-ray diffraction (XRD). Rietveld refinement showed that the major phase exists in tetragonal form with space group I4/m. Microstructural investigations revealed the formation of uniform grains. The electrical conductivity studied by impedance spectroscopy in the temperature range 300-600 °C was found to follow a thermally activated process. The sample with x = 0.01 showed the highest conductivity with lowest activation energy. The electrical conductivity of the system was discussed in terms of identified impurity phases and charge density [{{{Mo}}_{{{{Mo}}^{6 +}}}^{5 +} {}^' ]. The variation of electrical conductivity with composition was explained on the basis of X-ray photoelectron spectroscopy and XRD studies.

  2. HDO of guaiacol over NiMo catalyst supported on activated carbon derived from castor de-oiled cake

    Directory of Open Access Journals (Sweden)

    Viviana Ospina

    2015-08-01

    Full Text Available Physical and chemical activation methods were used to prepare two different activated carbons (ACs from castor de-oiled cake. H2O/CO2 mixture was used as the physical activating agent, and for chemical activation potassium carbonate (K2CO3 was used. For both materials, textural and chemical properties were characterized by N2 adsorption–desorption isotherms, thermogravimetric analysis (TGA, Fourier Transform Infrared Spectroscopy (FTIR, thermal programmed reduction (TPR, X-ray fluorescence (XRF, and scanning electron microscopy (SEM. The ACs were used as supports for NiMo sulfide catalysts, which were prepared by wetness impregnation and in-situ sulfided for the hydrodeoxygenation (HDO of guaiacol (GUA as a model compound of bio-oil. The HDO reaction was carried out in a typical batch reactor at 5 MPa of H2 and 350 °C. Under the same test conditions, commercial catalysts were also tested in the reaction. Although the commercial catalysts displayed higher GUA conversion, the prepared catalysts showed higher activity and non-oxygenated and saturated products yield. 

  3. Study of Effect of Quenching Deformation Influenced by 17CrNiMo6 Gear Shaft of Carburization

    Science.gov (United States)

    Pang, Zirui; Yu, Shenjun; Xu, Jinwu

    The 17CrNiMo6 steel is mainly used for the gear shaft of large modulus in many fields of heavy industry such as mining, transit, hoist, forging and so on[1]. The size of addendum circle and common normal line is changed a lot beyond the tolerance because of the long time of carburizing process and the out-of-step structural stress and thermal stress during the quenching process. And thus the posterior grinding efficiency and quality are influenced. In the paper comparison and analysis of the deformation affected by solid and hollow gear shafts were done and the methods of simulation and practice were both used. The results are as follows: the deformation of gear shaft was small before and after carburizing while that of gear shaft was large before and after quenching because of different cooling velocity, structure and hardness of each position. And the deformation of hollow was much smaller than that of solid. Therefore, if the hollow gear shaft is used, the waste of material will be decreased, and finishing cost will be reduced, and thus the technology of heat treatment will be optimized.

  4. High-resolution electron tomography study of an industrial Ni-Mo/gamma-Al2O3 hydrotreating catalyst.

    Science.gov (United States)

    de Jong, Krijn P; van den Oetelaar, Leon C A; Vogt, Eelco T C; Eijsbouts, Sonja; Koster, Abraham J; Friedrich, Heiner; de Jongh, Petra E

    2006-06-01

    The growing demand for high-quality transportation fuels requires their cost-effective production by hydrodesulfurization of crude oils using heterogeneous catalysts. To study the three-dimensional (3D) structure of such a commercial, sulfided Ni-Mo/gamma-Al2O3 catalyst, electron tomography was applied. The MoS2 particles form an interconnected complex structure within the mesopores of the alumina support. Spatial organization, morphology, and orientation of the MoS2 particles in the pores were resolved with sufficient accuracy to display the 6-A-spaced MoS2 crystal planes. The proximity of the MoS2 edge planes and more loosely interacting MoS2 basal planes to the alumina support showed the presence of pores smaller than 3 nm, which was confirmed by physisorption experiments. The actual shape of the MoS2 particles cannot be described by simple models as derived from studies on model catalysts. Electron tomography is a unique tool to study the actual 3D structure of complex industrial catalysts with sub-nanometer resolution.

  5. Kinetics study of leaching arsenic from Ni-Mo ore roasting in dust mixture of hydrochloric and sulfuric acids

    Institute of Scientific and Technical Information of China (English)

    侯晓川; 杨润德; 李贺; 曾理; 肖连生

    2014-01-01

    The kinetics of leaching arsenic from Ni-Mo ore roasting dust was investigated. The effects including leaching temperature, particle size of the smelter dust, stirring speed, the coefficientβ(the molar ratio of sodium chlorate to arsenic in the smelter dust) and the initial H+ concentration on leaching arsenic were studied. The results indicate that the leaching of arsenic increases sharply with the decrease of particle size. The orders of reaction with respect to H+ concentration and particle size are determinted to be 1.136 and-1.806, respectively.The leaching of arsenic reaches 99% under experimental conditions, the apparent activation energy is determined to be 11.157 kJ/mol, which is consistent with the values of activation energy for diffusion model. The kinetics equation of leaching arsenic from the roasting dust could be expressed by a semi-empirical equation as 1-2/3η-(1-η)2/3=k0(c[H+])1.136r0-1.806exp[(-11157/RT)t].

  6. Processing of spent NiMo and CoMo/Al2O3 catalysts via fusion with KHSO4.

    Science.gov (United States)

    Busnardo, Roberto Giovanini; Busnardo, Natália Giovanini; Salvato, Gustavo Nascimento; Afonso, Júlio Carlos

    2007-01-10

    This work describes a route for processing spent commercial hydrorefining (HDR) catalysts (CoMo and NiMo/Al2O3), containing support additives, for recovering active phase and support components. Samples were used as catalysts in diesel hydrotreaters. They had neither been submitted to mechanical stresses nor overheating while under operation. The route is based on fusion of samples with KHSO4. Four experimental parameters were optimized: reaction time, sample/flux mass ratio, temperature, and sample physical characteristics (ground/non-ground). After fusion, the solid was dissolved in water (90-100 degrees C); the insoluble matter presented low crystallization. Several phases were identified: silicates, spinel-like compounds and aluminosilicates. Cobalt, nickel, molybdenum and aluminum were recovered by conventional precipitation techniques or selective solvent-extraction procedures, with at least 85 wt.% yield. Final liquid colorless effluents are obtained as neutral solutions of alkali sulfates or chlorides and a water insoluble solid after fusion, which can be either sent to industrial dumps or co-processed. Fusion with KHSO4 was shown to be applicable to the catalysts of the present study, and the optimized experimental parameters are much less drastic than the conventional pyrometallurgical routes proposed in the literature.

  7. Self-Propagating High-Temperature Synthesis in the Ti-C-Ni-Mo System on Application of Powerful Ultrasound

    Science.gov (United States)

    Kulak, M. M.; Khina, B. B.

    2014-03-01

    An experimental setup has been developed and a study has been made of the self-propagating high-temperature synthesis in a Ti-C-Ni-Mo system under the conditions of action of ultrasonic vibrations. The influence of the amplitude of ultrasonic vibrations on the combustion rate and temperature and on the phase composition and structure of the derived composite material based on titanium carbide with a metal binder has been determined. The heat-transfer coefficient on the surface of a sample for vibrations at ultrasound frequency has been evaluated. Consideration has been given to possible mechanisms of influence of ultrasonic vibrations on the process of self-propagating high-temperature synthesis. It has been shown that the reduction in the synthesis temperature is due to the cooling of the sample because of the forced convection of the surrounding gas, whereas the change in the structure of the synthesized material is related to the change in the conditions of high-temperature heterogeneous interaction in the wave of self-propagating high-temperature synthesis.

  8. Beryllium coating produced by evaporation-condensation method and some their properties

    Energy Technology Data Exchange (ETDEWEB)

    Pepekin, G.I.; Anisimov, A.B.; Chernikov, A.S.; Mozherinn, S.I.; Pirogov, A.A. [SRI SIA Lutch., Podolsk (Russian Federation)

    1998-01-01

    The method of vacuum evaporation-condensation for deposition of beryllium coatings on metal substrates, considered in the paper, side by side with a plasma-spray method is attractive fon ITER application. In particular this technique may be useful for repair the surface of eroded tiles which is operated in a strong magnetic field. The possibility of deposition of beryllium coatings with the rate of layer growth 0.1-0.2 mm/h is shown. The compatibility of beryllium coating with copper or stainless steel substrate is provided due to intermediate barrier. The results of examination of microstructure, microhardness, porosity, thermal and physical properties and stability under thermal cycling of beryllium materials are presented. The value of thermal expansion coefficient and thermal conductivity of condensed beryllium are approximately the same as for industrial grade material produced by powder mettalurgy technique. However, the condensed beryllium has higher purity (up to 99.9-99.99 % wt.). (author)

  9. Preparation and activity evaluation of NiMoB/γ-Al2O3 catalyst by liquid-phase furfural hydrogenation

    Institute of Scientific and Technical Information of China (English)

    Shuqin Wei; Hongyou Cui; Jinghua Wang; Shuping Zhuo; Weiming Yi; Lihong Wang; Zhihe Li

    2011-01-01

    Amorphous MoNiB/γ-Al2O3 alloy catalysts were prepared by reducing NiCl2-6H2O and genation of furfural (FFR) as a probe reaction,the activity of MoNiB/γ-Al2O3 was examined. Compared to NiB and NiMoB,NiMoB/γ-Al2O3 exhibited excellent activity and selectivity towards furfuryl alcohol (FFA). After reaction for 3.0 h at 80 °C and 5.0 MPa in methanol,FFR conversion reached 99% with FFA yield of 91%. The effects of doping amount of Mo and calcination temperature before NaBH4 reduction on hydrogenation activity were also investigated. The optimum Mo/Ni atom ratio and calcination temperature were found to be 1:7 and 300 C,respectively. XRD patterns and SEM images indicated that NiMoB over the surface of γ-Al2O3 was amorphous and highly dispersed,which was responsible for the high thermal stability of the title catalyst.

  10. TiC Reinforcement Composite Coating Produced Using Graphite of the Cast Iron by Laser Cladding

    Directory of Open Access Journals (Sweden)

    Yanhui Liu

    2016-09-01

    Full Text Available In this study, a TiC-reinforced composite coating was produced to improve the wear resistance of a pearlite matrix grey iron using a pre-placed Ti powder by laser cladding. Results of scanning electron microscopy (SEM, X-ray diffractometer (XRD, and energy dispersive X-ray spectroscopy (EDS confirmed that the coating was composed of TiC particles and two kinds of α-Fe phase. The fine TiC particles were only a few microns in size and uniformly distributed on the matrix phase in the composite coating. The microstructure characteristic of the composite coating resulted in the microhardness rising to about 1000 HV0.3 (China GB/T 4342-1991 and the wear resistance significantly increased relative to the substrate. In addition, the fine and homogeneous solidification microstructure without graphite phase in the transition zone led to a good metallurgical bonding and transition between the coating and the substrate. It was of great significance for the cast iron to modify the surface and repair surface defects or surface damage.

  11. Electrodeposition of Ni-Mo nanoparticles for the electrocatalytic hydrogen evolution reaction; Electrodepositacion de nanoparticulas de Ni-Mo para la electrocatalisis de la reaccion de evolucion de hidrogeno

    Energy Technology Data Exchange (ETDEWEB)

    Videa, M.; Crespo, D.; Casillas, G.; Zavala, G. [Tecnologico de Monterrey Campus Monterrey, Monterrey, Nuevo Leon (Mexico)]. E-mail: mvidea@eitesm.mx

    2009-09-15

    This work reports on the generation of nickel- molybdenum deposits from the application of direct current in an electrolytic bath composed of a basic solution of NiSO{sub 4}, Na{sub 2}MoO{sub 4} and Na{sub 3}C{sub 6}H5O7. The working electrodes used were 1mm diameter vitreous carbon discs and carbon felt. The catalytic activity of the deposits was evaluated with cyclic voltamperometry in a 0.72M solution of H{sub 2}SO{sub 4}. Deposits were generated on the vitreous carbon discs, which showed catalytic activity for the HER. Deposits were obtained with better properties, showing a pulse of 200 mA/cm{sup 2}. The 42 mA/cm{sup 2} pulse experiments with varying durations showed that their catalytic capacities are better than expected, in spite of the use of small quantities of charge obtained with 90 ms and 300s. Low activity was observed in the absence of MoO{sub 4}{sup 2-} in the electrolytic bath during the electrodeposition process, indicating the importance of the presence of Mo to the catalytic activity. The deposits were inspected using atomic force microscopy (AFM). Though the electrodeposition on carbon felt is possible, the experiments were not reproducible because control over the active area of the electrode is difficult to achieve. NiMo nanoparticles on carbon filter fibers can be obtained using pulses with sufficient intensity and duration. [Spanish] En este trabajo se reporta la generacion de depositos de niquel-molibdeno mediante la aplicacion de corriente directa en un bano electrolitico compuesto por una solucion basica de NiSO{sub 4}, Na{sub 2}MoO{sub 4} y Na{sub 3}C{sub 6}H5O7. Se utilizaron como electrodos de trabajo discos de carbon vitreo de 1mm de diametro y fieltro de carbono. La actividad catalitica de los depositos fue evaluada mediante voltamperometria ciclica en una solucion 0.72M de H{sub 2}SO{sub 4}. Sobre los electrodos de carbon vitreo se generaron depositos que mostraron actividad catalitica para la REH. Depositos con mejores propiedades

  12. Photocatalytic Property and Reaction Mechanism of (Ni-Mo)/TiO2Nano Thin Film Evaluated with Congo Red%(Ni-Mo)/TiO2纳米薄膜光催化降解刚果红的性能与机理

    Institute of Scientific and Technical Information of China (English)

    李爱昌; 李桂花; 郑琰; 冯玲玲; 郑彦俊

    2012-01-01

    用恒电流复合电沉积方法制备(Ni-Mo)/TiO2薄膜,以扫描电子显微镜(SEM)、X射线衍射(XRD)、拉曼(Raman)光谱和紫外-可见漫反射光谱(UV-Vis DRS)对薄膜的表面形貌、晶相结构和光谱特性进行了表征,以刚果红为模拟污染物对薄膜的光催化性能进行了测定,并讨论了刚果红溶液的pH值对薄膜光催化活性的影响.采用循环伏安技术和向溶液中加入活性物种捕获剂的方法对薄膜光催化降解机理进行了探索.结果表明:(Ni-Mo)/TiO2薄膜是由粒径为50-100 nm TiO2纳米粒子相和纳米晶Ni-Mo固溶体相构成的复合薄膜.薄膜具有较高的光催化活性,卤钨灯照射80 min后,复合薄膜光催化刚果红的降解率是多孔TiO2(Degussa P25)/ITO(氧化铟锡)纳米薄膜的2.43倍.(Ni-Mo)/TiO2薄膜光催化活性的提高主要归因于薄膜层中有效形成的(Ni-Mo)/TiO2异质结和良好的电子通道,以及Ni-Mo纳米晶合金对溶解氧和激发电子还原反应的催化作用.分别给出了在紫外和可见光下薄膜光催化降解刚果红的反应机理.%(Ni-Mo)/TiO2 composite thin films were prepared by composite electroplating at a constant current. The surface morphology, phase structure, and optical characteristics of the thin films were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectrum, and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS), respectively. The photocatalytic properties of the (Ni-Mo)/TiO2 composite thin films were evaluated with Congo red as a model compound. The effects of pH of the Congo red aqueous solution on the photocatalytic activity of the (Ni-Mo)/TiO2 thin films were investigated. Using cyclic voltammetry technique and a method of adding active species scavengers to the solution, the mechanisms of photocatalytic degradation of the films were explored. The results show that the (Ni-Mo)/TiO2 films consist of crystalline grains of TiO2 in the size range of

  13. Producing Durable Continuously Reinforced Concrete Pavement using Glass-ceramic Coated Reinforcing Steel

    Science.gov (United States)

    2010-02-01

    Portland cement is manufactured by firing the clinker at 1400 C Enamel application produces no changes BUILDING STRONG® Treatment Average Peak...ceramic Coated Reinforcing Steel 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER... transition zone at the surface of the reinforcement steel is often the most permeable part of the concrete BUILDING STRONG® Schematic of Ceramic

  14. Improvement of the Corrosion Resistance of High Alloyed Austenitic Cr-Ni-Mo Stainless Steels by Solution Nitriding

    Institute of Scientific and Technical Information of China (English)

    Christine Eckstein; Heinz- Joachim Spies; Jochen Albrecht

    2004-01-01

    Characteristic features of austenitic steel grades combine a good corrosion resistance with a low hardness, wear resistance and scratch resistance. An interesting possibility for improving the wear behaviour of these steels without loss of their corrosion resistance lies in enriching the near surface region with nitrogen. The process of a solution nitriding allows the rise of the solution of nitrogen in the solid phase. On this state nitrogen increases the corrosion resistance and the tribilogical load-bearing capacity. The aim of the study was, to investigate the improvement of the pitting corrosion behaviour by solution nitriding. A special topic was to observe the effect of nitrogen by different molybdenum content. So austenitic stainless steels (18% Cr, 12% Ni, Mo gradation between 0.06 to 3.6%) had been solution nitrided. The samples could be prepared with various surface content of nitrogen from 0.04 to 0.45% with a step-by-step grinding. The susceptibility against pitting corrosion of these samples had been tested by determination of the stable pitting potential in 0.5M and 1M NaCl at 25℃. For the investigated steel composition and the used corrosion system there is no influence of molybdenum on the effectiveness of nitrogen. The influence of nitrogen to all of the determined parameters can be corrosion tests. Additionally surface investigations with an acid elektolyte (0,1M HCl + 0,4M NaCI) were performed. In this case the passivation effective nitrogen content increases markedly with rising molybdenum concentration of the steel.Obviously an interaction of Mo and N is connected with a strongly acid electrolyte.

  15. Bioactivity assessment of hydroxyapatite coatings produced by alkali conversion of monetite

    Energy Technology Data Exchange (ETDEWEB)

    Silva, M.H.P. da [Military Inst. of Engineering, Rio de Janeiro, RJ (Brazil); Soares, G.A. [Federal Univ. of Rio de Janeiro, RJ (Brazil); Elias, C.N. [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Matematica; Gibson, I.R. [London Univ. (United Kingdom). IRC Biomedical Materials; Best, S.M. [Cambridge Univ. (United Kingdom). Dept. of Metallurgy and Materials Science

    2001-07-01

    Commercially pure titanium sheets were coated with hydroxyapatite using three different routes: alkali conversion of monetite to hydroxyapatite utilising NH{sub 4}OH, KOH and NaOH solutions with pH=12.5. The hydroxyapatite coatings produced by each of the three different routes all exhibited similar morphologies and crystallinities, and hydroxyapatite was the only crystalline phase observed in all the coatings. The crystallinity and identification of the phases present were obtained by X-ray diffraction (XRD) analysis and the bioactivity was assessed according to the method developed by KOKUBO and co-workers. SEM analysis showed that all specimens exhibited areas with apatite precipitation from the SBF solution after 3 days immersion in SBF solution, irrespective of the alkaline solution used for the conversion process. This finding was confirmed by XRD analysis, which revealed a pattern corresponding to poorly-crystallinity hydroxyapatite. There appeared to be no effect of the ammonium, sodium or potassium ions from the different alkaline solutions used on the chemical conversion of monetite to hydroxyapatite on the properties of the resulting coating. (orig.)

  16. Review on materials & methods to produce controlled release coated urea fertilizer.

    Science.gov (United States)

    Azeem, Babar; KuShaari, KuZilati; Man, Zakaria B; Basit, Abdul; Thanh, Trinh H

    2014-05-10

    With the exponential growth of the global population, the agricultural sector is bound to use ever larger quantities of fertilizers to augment the food supply, which consequently increases food production costs. Urea, when applied to crops is vulnerable to losses from volatilization and leaching. Current methods also reduce nitrogen use efficiency (NUE) by plants which limits crop yields and, moreover, contributes towards environmental pollution in terms of hazardous gaseous emissions and water eutrophication. An approach that offsets this pollution while also enhancing NUE is the use of controlled release urea (CRU) for which several methods and materials have been reported. The physical intromission of urea granules in an appropriate coating material is one such technique that produces controlled release coated urea (CRCU). The development of CRCU is a green technology that not only reduces nitrogen loss caused by volatilization and leaching, but also alters the kinetics of nitrogen release, which, in turn, provides nutrients to plants at a pace that is more compatible with their metabolic needs. This review covers the research quantum regarding the physical coating of original urea granules. Special emphasis is placed on the latest coating methods as well as release experiments and mechanisms with an integrated critical analyses followed by suggestions for future research. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Optimization of Ni-Based WC/Co/Cr Composite Coatings Produced by Multilayer Laser Cladding

    Directory of Open Access Journals (Sweden)

    Andrea Angelastro

    2013-01-01

    Full Text Available As a surface coating technique, laser cladding (LC has been developed for improving wear, corrosion, and fatigue properties of mechanical components. The main advantage of this process is the capability of introducing hard particles such as SiC, TiC, and WC as reinforcements in the metallic matrix such as Ni-based alloy, Co-based alloy, and Fe-based alloy to form ceramic-metal composite coatings, which have very high hardness and good wear resistance. In this paper, Ni-based alloy (Colmonoy 227-F and Tungsten Carbides/Cobalt/Chromium (WC/Co/Cr composite coatings were fabricated by the multilayer laser cladding technique (MLC. An optimization procedure was implemented to obtain the combination of process parameters that minimizes the porosity and produces good adhesion to a stainless steel substrate. The optimization procedure was worked out with a mathematical model that was supported by an experimental analysis, which studied the shape of the clad track generated by melting coaxially fed powders with a laser. Microstructural and microhardness analysis completed the set of test performed on the coatings.

  18. Microstructure and mechanical properties of CuNiMo austempered ductile iron

    Directory of Open Access Journals (Sweden)

    Erić Olivera

    2004-01-01

    Full Text Available Microstructure and mechanical properties of Cu, Ni and Mo alloyed cast ductile iron have been investigated after austempering. Samples were austenitised at 860oC for 1h and then austempered at 320oC and 400oC in the interval from 0,5 to 5h. The X-ray diffraction technique and the light microscopy were utilized to investigate the bainitic transformation, while tensile and impact tests were performed for characterization of mechanical properties. By austempering at 320oC in the range between 2 and 5h, a microstructure typical for austempered ductile iron was produced, i.e. a mixture of free bainitic ferrite and highly carbon enriched retained austenite. The characteristic of the whole range of austempering at 400oC is the appearance of martensitic structure. The maximum impact energy (133 J coincides with the maximum value of volume fraction of retained austenite that was obtained after 2,5h of austempering at 320oC. The appearance of martensite during austempering at 400oC is the main cause for much lower tensile properties than at 320oC.

  19. Characterization of hard coatings produced by laser cladding using laser-induced breakdown spectroscopy technique

    Energy Technology Data Exchange (ETDEWEB)

    Varela, J.A.; Amado, J.M.; Tobar, M.J.; Mateo, M.P.; Yañez, A.; Nicolas, G., E-mail: gines@udc.es

    2015-05-01

    Highlights: • Chemical mapping and profiling by laser-induced breakdown spectroscopy (LIBS) of coatings produced by laser cladding. • Production of laser clads using tungsten carbide (WC) and nickel based matrix (NiCrBSi) powders. • Calibration by LIBS of hardfacing alloys with different WC concentrations. - Abstract: Protective coatings with a high abrasive wear resistance can be obtained from powders by laser cladding technique, in order to extend the service life of some industrial components. In this work, laser clad layers of self-fluxing NiCrBSi alloy powder mixed with WC powder have been produced on stainless steel substrates of austenitic type (AISI 304) in a first step and then chemically characterized by laser-induced breakdown spectroscopy (LIBS) technique. With the suitable laser processing parameters (mainly output power, beam scan speed and flow rate) and powders mixture proportions between WC ceramics and NiCrBSi alloys, dense pore free layers have been obtained on single tracks and on large areas with overlapped tracks. The results achieved by LIBS technique and applied for the first time to the analysis of laser clads provided the chemical composition of the tungsten carbides in metal alloy matrix. Different measurement modes (multiple point analyses, depth profiles and chemical maps) have been employed, demonstrating the usefulness of LIBS technique for the characterization of laser clads based on hardfacing alloys. The behavior of hardness can be explained by LIBS maps which evidenced the partial dilution of some WC spheres in the coating.

  20. Comparison of P-containing {gamma}-Al{sub 2}O{sub 3} supported Ni-Mo bimetallic carbide, nitride and sulfide catalysts for HDN and HDS of gas oils derived from Athabasca bitumen

    Energy Technology Data Exchange (ETDEWEB)

    Sundaramurthy, V.; Dalai, A.K. [Catalysis and Chemical Reaction Engineering Laboratories, Department of Chemical Engineering, University of Saskatchewan, Saskatoon, SK (Canada); Adjaye, J. [Syncrude Edmonton Research Centre, Edmonton, AB (Canada)

    2006-09-01

    Phosphorus containing {gamma}-Al{sub 2}O{sub 3} supported bimetallic Ni-Mo carbide, nitride and sulfide catalysts have been synthesized from an oxide precursor containing 12.73wt.% Mo, 2.54wt.% Ni and 2.38wt.% P and characterized by elemental analysis, pulsed CO chemisorption, surface area measurements, X-ray diffraction, temperature-programmed reduction and DRIFT spectroscopy of CO adsorption. DRIFT spectroscopy of adsorbed CO on activated catalysts showed that carbide and nitride catalysts have surface exposed sites of Mo{sup o+} (0Ni-Mo carbide, nitride and sulfide catalysts were compared against commercial Ni-Mo/Al{sub 2}O{sub 3} catalyst in a trickle bed reactor using light gas oil and heavy gas oil derived from Athabasca bitumen in the temperature range 340-370 and 375-400{sup o}C respectively at 8.8MPa. The gradual transformation of Ni-Mo carbide and nitride phases into Ni-Mo sulfide phases was observed during precoking period, and the formed Ni-Mo sulfide phases enhanced the HDN and HDS activities of carbide and nitride catalysts. The {gamma}-Al{sub 2}O{sub 3} supported Ni-Mo bimetallic sulfide catalyst was found to be more active for HDN and HDS of light gas oil and heavy gas oil than the corresponding carbide and nitride catalysts on the basis of unit weight. (author)

  1. Method of Producing a Film Coating by Matrix Assisted Pulsed Laser Deposition

    Science.gov (United States)

    1997-05-28

    N.C. 78,117 PATENT APPLICATION Inventor’s Name: R. Andrew McGill and Douglas B. Chrisey 1 in a technique called spin coating . These techniques have...several disadvantages. It is difficult with 2 the spin coating or spray coating methods to control the coating thickness precisely, or to ensure 3... Spin coating potentially provides a more uniform 5 coating surface than does spray coating, but nevertheless this method has the disadvantage that 6

  2. Efeito da omissão de N, NI, Mo, Co e S sobre os teores de N e S em feijoeiro

    Directory of Open Access Journals (Sweden)

    J. M. Jasmim

    2002-12-01

    Full Text Available Foi avaliado o efeito da omissão de N, Ni, Mo, Co e S sobre os teores de N e S em feijoeiros (Phaseolus vulgaris inoculados e não inoculados com Rhizobium, em casa de vegetação. O experimento foi realizado em um esquema fatorial com dois tipos de solo (Neossolo Flúvico, dois níveis de inoculação (com e sem, combinados com seis adubações: (a Completo (N, P, K, Ni, Mo, Co e S; (b sem N; (c sem Ni; (d sem Co; (e sem Mo; (f sem S. O delineamento experimental foi inteiramente casualizado com três repetições. Foram fornecidos 126 mg kg-1 de N (parcelados no plantio, aos 10 e 25 dias da emergência - DAE, 248 mg kg-1 de P, 117 de K e 48 de S, aplicados no solo, e 10, 250 e 10 mg L-1 de Ni, Mo e Co, respectivamente, aplicados via foliar aos nove DAE. A colheita foi efetuada aos 35 DAE, separando-se a folha indicadora das demais. A adubação nitrogenada aumentou o crescimento das plantas, indicando serem os solos deficientes em N, bem como reduziu os teores foliares de N e S. A omissão dos demais nutrientes não alterou o crescimento das plantas nem o teor de N foliar, mas a omissão de S reduziu, como esperado, o teor de S foliar.

  3. Three-Dimensional NiMoO4 Nanosheets Supported on a Carbon Fibers@Pre-Treated Ni Foam (CF@PNF) Substrate as Advanced Electrodes for Asymmetric Supercapacitors.

    Science.gov (United States)

    Zhou, Caixia; Yang, Wen; Zeng, Guangfeng; Lei, Ying; Gu, Li; Xi, Xianghui; Xiao, Dan

    2015-08-01

    Herein, we report a nanoarchitectured nickel molybdate/carbon fibers@pre-treated Ni foam (NiMoO4 /CF@PNF) electrode for supercapacitors. The synthesis of NiMoO4 /CF@PNF mainly consists of a direct chemical vapor deposition (CVD) growth of dense carbon fibers (CFs) onto pre-treated Ni foam (PNF) as the substrate, followed by in situ growth of NiMoO4 nanosheets (NSs) on the CF@PNF substrate by means of a hydrothermal process. The NiMoO4 /CF@PNF electrode exhibits a high areal capacitance (5.14 F cm(-2) at 4 mA cm(-2) ) and excellent cycling stability (97 % capacitance retention after 2000 cycles at 10 mA cm(-2) ). Furthermore, we have successfully assembled NiMoO4 NSs//activated carbon (AC) asymmetric supercapacitors, which can achieve an energy density of 45.6 Wh kg(-1) at 674 W kg(-1) , and excellent stability with 93 % capacitance retention after 2000 cycles at 5 mA cm(-2) . These superior properties hold great promise for energy-storage applications.

  4. Prepration of Nano-Crystalline TiO2/(Ni-Mo) Electrode and Its Photoelectrocatalytic Performance in the Neutral Medium%TiO2/(Ni-Mo)纳米薄膜电极的制备及其在中性介质中的光电催化性能

    Institute of Scientific and Technical Information of China (English)

    赵娣; 戴富才; 李月娟; 李爱昌

    2010-01-01

    在Cu基体上电沉积Ni-Mo合金后,通过溶胶-凝胶法制备了纳米TiO2修饰Ni-Mo合金电极.利用阳极极化曲线测试了TiO2/(Ni-Mo)薄膜电极在0.5mol/L Na2SO4溶液中的光电催化性能,考察了烧结温度、TiO2膜层厚度对电极性能的影响.结果表明:在400℃下烧结1h、拉膜9次制备的TiO2/(Ni-Mo)电极,光电流变化最大,光响应最明显.最后利用交流阻抗法测定了最佳条件下制备的电极的阻抗性能,光照后的TiO2/(Ni-Mo)薄膜电极的法拉第阻抗变小,说明该电极表现出良好的光电催化性能.

  5. Co-blasting of titanium surfaces with an abrasive and hydroxyapatite to produce bioactive coatings: substrate and coating characterisation.

    Science.gov (United States)

    Dunne, Conor F; Twomey, Barry; O'Neill, Liam; Stanton, Kenneth T

    2014-01-01

    The aim of this work is to assess the influence of two blast media on the deposition of hydroxyapatite onto a titanium substrate using a novel ambient temperature coating technique named CoBlast. CoBlast was developed to address the problems with high temperature coating techniques. The blasting media used in this study were Al2O3 and a sintered apatite powder. The prepared and coated surfaces were compared to plasma sprayed hydroxyapatite on the same substrates using the same hydroxyapatite feedstock powder. X-ray diffraction analysis revealed the coating crystallinity was the same as the original hydroxyapatite feedstock powder for the CoBlast samples while evidence of amorphous hydroxyapatite phases and β-TCP was observed in the plasma sprayed samples. The blast media type significantly influences the adhesive strength of the coating, surface roughness of both the substrate and coating and the microstructure of the substrate. The coating adhesion increased for the CoBlasted samples from 50 MPa to 60 MPa for sintered apatite powder and alumina, respectively, while plasma spray samples were significantly lower (5 MPa) when tested using a modified pull-test. In conclusion, the choice of blast medium is shown to be a key parameter in the CoBlast process. This study indicates that sintered apatite powder is the most suitable candidate for use as a blast medium in the coating of medical devices.

  6. Effect of MCM-41 on the physicochemical properties of Mo and NiMo catalysts and their performance in DBT conversion

    Energy Technology Data Exchange (ETDEWEB)

    Grzechowiak, Jolanta R.; Mrozinska, Karolina; Masalska, Aleksandra [Department of Chemistry and Technology of Fuel, Faculty of Chemistry, Wroclaw University of Technology, 7/9 Gdanska Str., 50-344 Wroclaw (Poland); Goralski, Jacek; Rynkowski, Jacek [Institute of General and Ecological Chemistry, Technical University of Lodz, 36 Zwirki Str., 90-924 Lodz (Poland); Tylus, Wlodzimierz [Institute of Inorganic Technology, Faculty of Chemistry, Wroclaw University of Technology, Smoluchowskiego Str., 50-353 Wroclaw (Poland)

    2006-05-15

    The influence of mesoporous materials on the properties and HDS activity of Mo and NiMo catalysts was investigated for supports containing 50wt.% of MCM-41. A series of catalysts was characterized by different techniques (S{sub BET}, TPD-NH{sub 3}, TPR, SEM, XPS) and tested in dibenzothiophene (DBT) conversion. On the surface of the catalysts containing mesoporous materials, agglomerations of the Mo oxo-species were observed. The presence of MCM-41 in the support visibly weakened the promoting effect of TiO{sub 2} on the reducibility of Mo oxides. The results of DBT HDS showed that the NiMo catalyst supported on MCM-41 was not only less efficient than that supported on Al{sub 2}O{sub 3} but also that supported on Al{sub 2}O{sub 3}-TiO{sub 2}. From the distribution of DBT HDS products we can conclude that over catalysts containing MCM-41 the desulphurization of DBT runs mostly via the DDS route. (author)

  7. Synthesis, characterization, and catalytic activity of sulfided silico-alumino-titanate (Si-Al-Ti) mixed oxides xerogels supported Ni-Mo catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Al-Adwani, H.A.; Thammachote, N.; Anthony, R.G. [Texas A and M Univ., College Station, TX (United States); Gardner, T.J. [Sandia National Labs., Albuquerque, NM (United States)

    1998-07-25

    Layered semicrystalline silico-alumino-titanate (Si-Al-Ti) mixed oxides were synthesized by a modified sol-gel method with hydrothermal synthesis temperatures less than 200 C and autogenic pressure. The solid products are semicrystalline materials with a surface area of 136--367 m{sup 2}/g and a monomodal pore size distribution with an average pore diameter of 36--47 {angstrom}. The catalytic activity for pyrene hydrogenation in a batch reactor at 300 C and 500 psig was determined for sulfided Ni-Mo supported on the Si-Al-Ti mixed oxide. The activity was a function of the support composition, the heat treatment before and after loading the active metals, the addition of organic templates, and different methods of metal loading. The most active sulfided Ni-Mo/Si-Al-Ri catalyst has an activity in the same range as the commercial catalyst, Shell 324, but the metal loading is 37% less than the commercial catalyst.

  8. Synthesis, Characterization, and Catalytic Activity of Sulfided Silico-Alumino-Titanate (Si-Al-Ti) Mixed Oxides Xerogels Supported Ni-Mo Catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Al-Adwani, H.A.; Anthony, R.G.; Gardner, T.J.; Thammachote, N.

    1999-02-24

    Layered semicrystalline silico-alumino-titanate (Si-Al-Ti) mixed oxides were synthesized by a modified sol-gel method with hydrothermal synthesis temperatures less than 200 C and autogenic pressure. The solid products are semicrystalline materials with a surface area of 136-367 m{sup 2}/g and a monomodal pore size distribution with an average pore diameter of 3.6-4.7 nrn. The catalytic activity for pyrene hydrogenation in a batch reactor at 300 C and 500 psig was determined for sulfided Ni-Mo supported on the Si-Al-Ti mixed oxide. The activity was a function of the support composition the heat treatment before and after loading the active metals, the addition of organic templates, and different methods of metal loading. The most active sulfided Ni-Mo/Si-Al-Ti catalyst has an activity in the same range as the commercial catalyst, Shell 324, but the metal loading is 37% less than the commercial catalyst.

  9. Microstructural Modification of Laser-Deposited High-Entropy CrFeCoNiMoWC Alloy by Friction Stir Processing: Nanograin Formation and Deformation Mechanism

    Science.gov (United States)

    Li, Ruidi; Wang, Minbo; Yuan, Tiechui; Song, Bo; Shi, Yusheng

    2017-02-01

    Nanostructured CrFeCoNiMoWC high-entropy alloy layer was developed through laser-melting deposition and severe plastic deformation (SPD). The laser-deposited CrFeCoNiMoWC alloy consists of dendritic and subeutectic with a continuous network structure. After SPD, the laser-deposited microstructure with grain size 3 to 4 μm was transformed into nanostructure with grain size 5 to 100 nm and the continuous networks were crushed into dispersed nanoparticles. The new phases of WC and Co3W were presented in the plastic zone after SPD due to the worn debris of the SPD tool. More interestingly, amorphous phase was found in the plastic zone, owing to the high temperature, high hydrostatic pressure, and large shear stress. The refined microstructure resulted in the enhancement of microhardness and electrochemical corrosion property. Many nanotwins were detected in the plastic zone; thus, strengthening mechanisms were reasonably inferred as twinning strengthening, work hardening, dispersion strengthening, refinement strengthening, and dislocation strengthening. The Lomer-Cottrell lock, full dislocation interacting with a partial dislocation at the twinning boundary, and high density of dislocation at the twinning boundary, stacking fault, and grain boundary were observed, which account for the property enhancement of the nanocrystalline.

  10. Study of 13Cr-4Ni-(Mo (F6NM Steel Grade Heat Treatment for Maximum Hardness Control in Industrial Heats

    Directory of Open Access Journals (Sweden)

    Massimo De Sanctis

    2017-09-01

    Full Text Available The standard NACE MR0175 (ISO 15156 requires a maximum hardness value of 23 HRC for 13Cr-4Ni-(Mo steel grade for sour service, requiring a double tempering heat treatment at temperature in the range 648–691 °C for the first tempering and 593–621 °C for the second tempering. Difficulties in limiting alloy hardness after the tempering of forged mechanical components (F6NM are often faced. Variables affecting the thermal behavior of 13Cr-4Ni-(Mo during single and double tempering treatments have been studied by means of transmission electron microscopy (TEM observations, X-ray diffraction measurements, dilatometry, and thermo-mechanical simulations. It has been found that relatively low Ac1 temperatures in this alloy induce the formation of austenite phase above 600 °C during tempering, and that the formed, reverted austenite tends to be unstable upon cooling, thus contributing to the increase of final hardness via transformation to virgin martensite. Therefore, it is necessary to increase the Ac1 temperature as much as possible to allow the tempering of martensite at the temperature range required by NACE without the detrimental formation of virgin martensite upon final cooling. Attempts to do so have been carried out by reducing both carbon (<0.02% C and nitrogen (<100 ppm levels. Results obtained herein show final hardness below NACE limits without an unacceptable loss of mechanical strength.

  11. A comparative study on improved Arrhenius-type and artificial neural network models to predict high-temperature flow behaviors in 20MnNiMo alloy.

    Science.gov (United States)

    Quan, Guo-zheng; Yu, Chun-tang; Liu, Ying-ying; Xia, Yu-feng

    2014-01-01

    The stress-strain data of 20MnNiMo alloy were collected from a series of hot compressions on Gleeble-1500 thermal-mechanical simulator in the temperature range of 1173 ∼ 1473 K and strain rate range of 0.01 ∼ 10 s(-1). Based on the experimental data, the improved Arrhenius-type constitutive model and the artificial neural network (ANN) model were established to predict the high temperature flow stress of as-cast 20MnNiMo alloy. The accuracy and reliability of the improved Arrhenius-type model and the trained ANN model were further evaluated in terms of the correlation coefficient (R), the average absolute relative error (AARE), and the relative error (η). For the former, R and AARE were found to be 0.9954 and 5.26%, respectively, while, for the latter, 0.9997 and 1.02%, respectively. The relative errors (η) of the improved Arrhenius-type model and the ANN model were, respectively, in the range of -39.99% ∼ 35.05% and -3.77% ∼ 16.74%. As for the former, only 16.3% of the test data set possesses η-values within ± 1%, while, as for the latter, more than 79% possesses. The results indicate that the ANN model presents a higher predictable ability than the improved Arrhenius-type constitutive model.

  12. Synthesis, Characterization, and Catalytic Activity of Sulfided Silico-Alumino-Titanate (Si-Al-Ti) Mixed Oxides Xerogels Supported Ni-Mo Catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Al-Adwani, H.A.; Anthony, R.G.; Gardner, T.J.; Thammachote, N.

    1999-02-24

    Layered semicrystalline silico-alumino-titanate (Si-Al-Ti) mixed oxides were synthesized by a modified sol-gel method with hydrothermal synthesis temperatures less than 200 C and autogenic pressure. The solid products are semicrystalline materials with a surface area of 136-367 m{sup 2}/g and a monomodal pore size distribution with an average pore diameter of 3.6-4.7 nrn. The catalytic activity for pyrene hydrogenation in a batch reactor at 300 C and 500 psig was determined for sulfided Ni-Mo supported on the Si-Al-Ti mixed oxide. The activity was a function of the support composition the heat treatment before and after loading the active metals, the addition of organic templates, and different methods of metal loading. The most active sulfided Ni-Mo/Si-Al-Ti catalyst has an activity in the same range as the commercial catalyst, Shell 324, but the metal loading is 37% less than the commercial catalyst.

  13. Trace- and rare-earth element geochemistry and Pb-Pb dating of black shales and intercalated Ni-Mo-PGE-Au sulfide ores in Lower Cambrian strata, Yangtze Platform, South China

    Science.gov (United States)

    Jiang, Shao-Yong; Chen, Yong-Quan; Ling, Hong-Fei; Yang, Jing-Hong; Feng, Hong-Zhen; Ni, Pei

    2006-08-01

    The Lower Cambrian black shale sequence of the Niutitang Formation in the Yangtze Platform, South China, hosts an extreme metal-enriched sulfide ore bed that shows >10,000 times enrichment in Mo, Ni, Se, Re, Os, As, Hg, and Sb and >1,000 times enrichment in Ag, Au, Pt, and Pd, when compared to average upper continental crust. We report in this paper trace- and rare-earth-element concentrations and Pb-Pb isotope dating for the Ni-Mo-PGE-Au sulfide ores and their host black shales. Both the sulfide ores and their host black shales show similar trace-element distribution patterns with pronounced depletion in Th, Nb, Hf, Zr, and Ti, and extreme enrichment in U, Ni, Mo, and V compared to average upper crust. The high-field-strength elements, such as Zr, Hf, Nb, Ta, Sc, Th, rare-earth elements, Rb, and Ga, show significant inter-element correlations and may have been derived mainly from terrigenous sources. The redox sensitive elements, such as V, Ni, Mo, U, and Mn; base metals, such as Cu, Zn, and Pb; and Sr and Ba may have been derived from mixing of seawater and venting hydrothermal sources. The chondrite-normalized REE patterns, positive Eu and Y anomalies, and high Y/Ho ratios for the Ni-Mo-PGE-Au sulfide ores are also suggestive for their submarine hydrothermal-exhalative origin. A stepwise acid-leaching Pb-Pb isotope analytical technique has been employed for the Niutitang black shales and the Ni-Mo-PGE-Au sulfide ores, and two Pb-Pb isochron ages have been obtained for the black shales (531±24 Ma) and for the Ni-Mo-PGE-Au sulfide ores (521±54 Ma), respectively, which are identical and overlap within uncertainty, and are in good agreement with previously obtained ages for presumed age-equivalent strata.

  14. Structure and Properties Characterization of Ceramic Coatings Produced on Steel Using a Combined Technique

    Institute of Scientific and Technical Information of China (English)

    SHENDe-jiu; WANGYu-lin; GUWei-chao; XINGGuang-zhong

    2004-01-01

    Metallurgically bonded ceramic coatings were prepared on a steel surface with a combined method of arc spraying and micro-arc oxidation for the first time. Coatings were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Point and line distribution of elements of the ceramic coatings were determined using energy dispersive spectroscopy (EDS). Coatings abrasive wear resistance, corrosion resistance and hot impact property were assessed respectively. The property test results show that metallurgically bonded ceramic coatings were formed on aluminum coatings and the ceramic coatings is mainly composed of α-Al2O3, γ-Al2O3, θ-Al2O3 and a little amorphous. The coatings possess excellent abrasive wear, corrosion and hot shock resistance, which can in part be attributed to the gradual distribution of different phases from surface to the substrate.

  15. A comparative study of the corrosion performance of TiN, Ti(B,N) and (Ti,Al)N coatings produced by physical vapour deposition methods

    Energy Technology Data Exchange (ETDEWEB)

    Aromaa, J.; Ronkainen, H.; Mahiout, A.; Hannula, S.P. (Technical Research Centre of Finland, Espoo (Finland)); Leyland, A.; Matthews, A. (Univ. of Hull (United Kingdom)); Matthes, B.; Broszeit, E. (Technische Hochschule Darmstadt (Germany))

    1991-07-07

    Thin film coatings produced by physical vapour deposition methods often exhibit porosity. Local defects can cause local and rapid corrosion of the base material. The porosity is difficult to estimate and electrochemical methods are most suitable for evaluating the corrosion resistance of the coated material. This paper compares the corrosion resistance of TiN, Ti(B,N), (Ti,Al)N- and TiB{sub 2}-coated ASP 23 high speed steel. For the materials studied here the corrosion performance of TiB{sub 2}-coated samples was poor. Ti(B,N) coatings obtained by two different methods were quite similar even though the calculated porosity of the coating produced by magnetron sputtering was lower than that of coatings produced by the electron beam technique. These coatings had similar or slightly better corrosion resistance than (Ti,Al)N coatings with a high aluminium-to-titanium ratio. (Ti,Al)N coatings with a low aluminium-to-titanium ratio were better than coatings with a high aluminium-to-titanium ratio. TiN coatings were better than other types excluding (Ti,Al)N+AlN layer coatings, which performed best. (Ti,Al)N+AlN coatings have an insulating layer on top of the coating, which increases the polarization resistance and decreases the corrosion current density. (orig.).

  16. Tribological and Corrosion Properties of Nickel/TiC Bilayered Coatings Produced by Electroless Deposition and PACVD

    Science.gov (United States)

    Shanaghi, Ali; Chu, Paul K.

    2016-11-01

    Ni/TiC bilayered coatings are deposited on hot-working steel (H11) by plasma-assisted chemical vapor deposition and electroless technique. The TiC layer is deposited at 490 °C using a gas mixture of TiCl4, CH4, H2, and Ar, and a dense nanostructured TiC coating with minimum excessive carbon phases and low chlorine concentration is produced. The effects of the Ni intermediate layer on the microstructure, tribology, and corrosion behavior of the nanostructured TiC coating are investigated. The friction coefficient of the Ni/TiC bilayered coating (Ni thickness = 4 µm) at 500 cycles is much smaller than that of the coating without the Ni intermediate layer. The smallest friction coefficient is about 0.2, and the hardness values of the Ni/TiC bilayered samples with three different Ni layer thicknesses of 2, 4, and 6 µm are 2534, 3070, and 2008 Hv, respectively. The wear mechanism of the Ni/TiC bilayered coatings is abrasive induced by plastic deformation and fatigue during the sliding process. The smaller groove width on the 4-µm electroless nickel-Ni3P/TiC bilayered coating correlates with the larger H/ E ratio and the 4-µm nickel/TiC bilayered sample shows the better wear resistance. The polarization resistance of the 6-µm electroless nickel-Ni3P/TiC coating in 0.05 M NaCl and 0.5 M H2SO4 increases by about 8 and 15 times, respectively. The Ni intermediate layer increases the toughness of the coating and adhesion between the hard coating and steel substrate thereby enhancing the tribological properties and corrosion resistance.

  17. Tribological and Corrosion Properties of Nickel/TiC Bilayered Coatings Produced by Electroless Deposition and PACVD

    Science.gov (United States)

    Shanaghi, Ali; Chu, Paul K.

    2016-10-01

    Ni/TiC bilayered coatings are deposited on hot-working steel (H11) by plasma-assisted chemical vapor deposition and electroless technique. The TiC layer is deposited at 490 °C using a gas mixture of TiCl4, CH4, H2, and Ar, and a dense nanostructured TiC coating with minimum excessive carbon phases and low chlorine concentration is produced. The effects of the Ni intermediate layer on the microstructure, tribology, and corrosion behavior of the nanostructured TiC coating are investigated. The friction coefficient of the Ni/TiC bilayered coating (Ni thickness = 4 µm) at 500 cycles is much smaller than that of the coating without the Ni intermediate layer. The smallest friction coefficient is about 0.2, and the hardness values of the Ni/TiC bilayered samples with three different Ni layer thicknesses of 2, 4, and 6 µm are 2534, 3070, and 2008 Hv, respectively. The wear mechanism of the Ni/TiC bilayered coatings is abrasive induced by plastic deformation and fatigue during the sliding process. The smaller groove width on the 4-µm electroless nickel-Ni3P/TiC bilayered coating correlates with the larger H/E ratio and the 4-µm nickel/TiC bilayered sample shows the better wear resistance. The polarization resistance of the 6-µm electroless nickel-Ni3P/TiC coating in 0.05 M NaCl and 0.5 M H2SO4 increases by about 8 and 15 times, respectively. The Ni intermediate layer increases the toughness of the coating and adhesion between the hard coating and steel substrate thereby enhancing the tribological properties and corrosion resistance.

  18. Structure and properties of Ti-C-B coatings produced by non-vacuum electron beam cladding

    Science.gov (United States)

    Lenivtseva, O. G.; Belousova, N. S.; Lozhkina, E. A.; Zimoglyadova, T. A.; Samoylenko, V. V.; Chuchkova, L. V.

    2016-11-01

    Cp-Ti/TiB+TiC wear-resistance coatings produced by non-vacuum electron beam cladding of boron carbide and titanium powders are studied in the paper. The X-ray phase analysis of the composite coatings microstructure showed that titanium carbide and boride reinforcing particles are evolved during the process. The obtained data are in good agreement with results of optical and electron microscopy. Undissolved particles of the initial boron carbide powder are detected in the coatings. The microhardness test as well as wear resistance test of materials under conditions of loose abrasive particles are conducted. It is established that the precipitation of reinforcing particles improves the tribological properties of the composite coatings.

  19. X-Ray Phase Analysis Of Nitrided Layers Of X2CrNiMo17-12-2 Austenitic Steel

    Directory of Open Access Journals (Sweden)

    Frączek T.

    2015-09-01

    Full Text Available This work presents the results of diffraction analyses carried out using X-ray phase analyses (XRD and GIXRD of nitrided layers of X2CrNiMo17-12-2 austenitic steel. Plasma nitriding process was c arried out in the temperature range of 325 ÷ 400 °C and time of 2 ÷ 4 h. Hydrogen-nitrogen plasma was used as reactive atmosphere (H2 75% + N2 25% with pressure of 150 Pa. On the basis of the X-ray analyses it was stated that the obtained nitrided layers consisted of a subsurface layer of chromium nitrides and a zone of nitrogen saturated austenite.

  20. Development of the fundamentals of melting and casting technology of Al-Me (Cr, Ni, Mo, W, Ti master alloys used for modification of microstructure in silumins

    Directory of Open Access Journals (Sweden)

    J. Piatkowski

    2009-04-01

    Full Text Available The study presents the technological backgrounds of the process of melting and casting Al-Cr, Al-Ni, Al-Mo, Al-W and Al-Ti masteralloys, used as refiners of the microstructure of cast silumins. Basing on the analysis of phase equilibrium diagrams for an Al-Me (Cr, Ni, Mo, W, Ti system at a temperature of 900oC, the characteristic intermetallic phases of AlxMey were investigated. Due to their similarity with Al and Si in respect of both structure and lattice arrangement, these phases may act as heterogeneous nuclei and promote solution hardening during, e.g., heat treatment. Using the method of thermal analysis ATD, the temperature was plotted in function of time, and then the characteristic values of the solidification parameters of master alloys were read out from the respective curves.

  1. Dry wear behaviors of wear resistant composite coatings produced by laser cladding

    Institute of Scientific and Technical Information of China (English)

    Jiang Xu; Wenjin Liu; Minlin Zhong

    2004-01-01

    Using different proportional mixtures of Ni-coated MoS2, TiC and pure Ni powders, new typical wear resistant and selflubricant coatings were formed on low carbon steel by laser cladding process. The microstructures and phase composition of the composite coatings were studied by SEM and XRD. The typical microstructure of the composite coating is composed of multisulfide phases including binary element sulfide and ternary element sulfide, γ-Ni, TiC and Mo2C. Wear tests were carried out using an FALEX-6 type pin-on-disc machine. The friction coefficient and mass loss of three kinds of MoS2/TiC/Ni laser clad coatings are lower than those of quenched 45 steel, and the worn surfaces of the laser cladding coatings are very smooth. Because of high hardness combined with low friction, the laser cladding composite coating with a mixture of 70% Ni-coated MoS2, 20%TiC and 10%pure Ni powder presents better wear behaviors than the composite coating with other powder blends. The composition analysis of the worn surface of GCr15 bearing steel shows that the transferred film from the laser cladding coating to the opposite surface of GCr15beating steel contains an amount of sulfide, which can change the micro-friction mechanism and lead to a reduced friction coefficient.

  2. Producing cobalt–graphene composite coating by pulse electrodeposition with excellent wear and corrosion resistance

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Cansen; Su, Fenghua, E-mail: fhsu@scut.edu.cn; Liang, Jizhao

    2015-10-01

    Graphical abstract: - Highlights: • Graphene oxide/cobalt coatings are synthesized by pulse electrodeposition. • Incorporating GO refines the grain size and changes the microstructure of the coating. • Incorporating GO greatly improves the friction reduction and wear resistance of the coating. • The corrosion resistance is enhanced by the incorporation of GO. - Abstract: Cobalt (Co) and graphene oxide/cobalt (GO/Co) composite coatings were fabricated by pulse electrodeposition technique from an aqueous bath containing cobalt sulfate and GO, etc. Effect of the incorporations of GO on morphology, phase structure, average grain size and corrosion and wear resistance of the resulting composite coatings were evaluated in detail. Scanning electron microscope (SEM) and energy dispersed X-ray (EDX) show that the GO nanosheets disperse homogeneously in the composite coating and the incorporations of GO change the morphologies of the deposit from conical shaped structure to protruding structure. In addition, the co-deposition GO with Co ions favor the formation of hcp (1 0 0), (0 0 2) and (1 0 1) textures in the composite coating and have functions of grain refining and hardness enhancement. The wear tests show that the incorporations of GO in the coating improve the wear resistance and friction reduction of the deposit. The electrochemical corrosion tests using potentiodynamic polarization and electrochemical impedance spectroscopy show that the GO/Co composite coating possesses better corrosion resistance than the pure Co coating.

  3. NiCo2S4@NiMoO4 Core-Shell Heterostructure Nanotube Arrays Grown on Ni Foam as a Binder-Free Electrode Displayed High Electrochemical Performance with High Capacity.

    Science.gov (United States)

    Zhang, Yan; Xu, Jie; Zheng, Yayun; Zhang, Yingjiu; Hu, Xing; Xu, Tingting

    2017-12-01

    Core-shell-structured system has been proved as one of the best architecture for clean energy products owing to its inherited superiorities from both the core and the shell part, which can provide better conductivity and high surface area. Herein, a hierarchical core-shell NiCo2S4@NiMoO4 heterostructure nanotube array on Ni foam (NF) (NiCo2S4@NiMoO4/NF) has been successfully fabricated. Because of its novel heterostructure, the capacitive performance has been enhanced. A specific capacitance up to 2006 F g(-1) was obtained at a current density of 5 mA cm(-2), which was far higher than that of pristine NiCo2S4 nanotube arrays (about 1264 F g(-1)). More importantly, NiCo2S4@NiMoO4/NF and active carbon (AC) were congregated as positive electrode and negative electrode in an asymmetric supercapacitor. As-fabricated NiCo2S4@NiMoO4/NF//AC device has a good cyclic behavior with 78% capacitance retention over 2000 cycles, and exhibits a high energy density of 21.4 Wh kg(-1) and power density of 58 W kg(-1) at 2 mA cm(-2). As displayed, the NiCo2S4@NiMoO4/NF core-shell herterostructure holds great promise for supercapacitors in energy storage.

  4. Microanalyses of the hydroxyl-poly-calcium sodium phosphate coatings produced by ion beam assisted deposition

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Thin calcium phosphate coatings on titanium alloy substrates wereprepared by Ar+ ion beam assisted deposition (IBAD) from hydroxyl-poly-calciumsodium phosphate (HPPA) target. The coatings were analyzed by XRD, FTIR, XPS.These analyses revealed that the as-deposited films were amorphous or no apparentcrystallinity. No distinct absorption band of the hydroxyl group was observed in FTIRspectra of the coatings but new absorption bands were presented for CO3-2. Thecalcium to phosphorous ratio of these coatings in different IBAD conditions variedfrom 0.46 to 3.36.

  5. Study on Fe-Based Coating Produced by Plasma Surface Metallurgy

    Institute of Scientific and Technical Information of China (English)

    LI Hui-qi; LIU Bang-wu; LI Hui-dong; ZHANG Li-min; LI Min; SUN Yu-zong

    2004-01-01

    In the paper, plasma surface metallurgy was performed using Fe-based powder on steel substrate. The microstructure and microhardness of the coating have been analyzed. On the base of orthogonal comparison tests,influences of many factors on the cracking sensibility of plasma metallurgy coating have also been studied. The results indicate that substrate and its surface condition, processing parameters and components of plasma metallurgy coating have great effects on cracking sensibility of plasma metallurgy coating. Through changing these factors, it is possible to reduce cracks and promote the applications of this technology.Key Words: plasma surface metallurgy, microstructure, microhardness, cracking sensibility

  6. Study on Fe-Based Coating Produced by Plasma Surface Metallurgy

    Institute of Scientific and Technical Information of China (English)

    LIHui-qi; LIUBang-wu; LIHui-dong; ZHANGLi-min; LIMin; SUNYu-zong

    2004-01-01

    In the paper, plasma surface metallurgy was performed using Fe-based powder on steel substrate. The microstructure and microhardness of the coating have been analyzed. On the base of orthogonal comparison tests, influences of many factors on the cracking sensibility of plasma metallurgy coating have also been studied. The results indicate that substrate and its surface condition, processing parameters and components of plasma metallurgy coating have great effects on cracking sensibility of plasma metallurgy coating. Through changing these factors, it is possible to reduce cracks and promote the applications of this technology.

  7. Investigation of coatings of austenitic steels produced by supersonic laser deposition

    Science.gov (United States)

    Gorunov, A. I.; Gilmutdinov, A. Kh.

    2017-02-01

    The structure and properties of stainless austenitic steel coatings obtained by the supersonic laser deposition are studied in the paper. Implantation of the powder particles into the substrate surface and simultaneous plastic deformation at partial melting improved the mechanical properties of the coatings - tensile strength limit was 650 MPa and adhesion strength was 105 MPa. It was shown that insufficient laser power leads to disruption of the deposition process stability and coating cracking. Surface temperature increase caused by laser heating above 1300 °C resulted in coating melting. The X-ray analysis showed that radiation intensifies the cold spray process and does not cause changes in the austenitic base structure.

  8. Diffusion Barrier Coating System and Oxidation Behavior of Coated Alloys

    Institute of Scientific and Technical Information of China (English)

    T.NARITA

    2009-01-01

    @@ 1 Introduction Research into the formation of Re-based alloys is in progress in our laboratory to provide a diffusion barrier layer between heat-resistant alloys and Al reservoir layers, which assist in the formation and maintenance a protective Al2O3 scale for long periods. Coatings with a two-layered structure comprised of inner Re-based alloy layer and outer β-NiAl layer with or without Pt addition were successfully formed on various heat resistant alloys such as Ni-based singlecrystal superalloys, Ni-based heat resistant alloys, NiMo based alloy, Ni-Cr based alloy, and Fe-based alloys. The duplex layer coating proposed is generally termed a diffusion barrier coating system; DBC system.

  9. The erosion performance of particle reinforced metal matrix composite coatings produced by co-deposition cold gas dynamic spraying

    Science.gov (United States)

    Peat, Tom; Galloway, Alexander; Toumpis, Athanasios; McNutt, Philip; Iqbal, Naveed

    2017-02-01

    This work reports on the erosion performance of three particle reinforced metal matrix composite coatings, co-deposited with an aluminium binder via cold-gas dynamic spraying. The deposition of ceramic particles is difficult to achieve with typical cold spray techniques due to the absence of particle deformation. This issue has been overcome in the present study by simultaneously spraying the reinforcing particles with a ductile metallic binder which has led to an increased level of ceramic/cermet particles deposited on the substrate with thick (>400 μm) coatings produced. The aim of this investigation was to evaluate the erosion performance of the co-deposited coatings within a slurry environment. The study also incorporated standard metallographic characterisation techniques to evaluate the distribution of reinforcing particles within the aluminium matrix. All coatings exhibited poorer erosion performance than the uncoated material, both in terms of volume loss and mass loss. The Al2O3 reinforced coating sustained the greatest amount of damage following exposure to the slurry and recorded the greatest volume loss (approx. 2.8 mm3) out of all of the examined coatings. Despite the poor erosion performance, the WC-CoCr reinforced coating demonstrated a considerable hardness increase over the as-received AA5083 (approx. 400%) and also exhibited the smallest free space length between adjacent particles. The findings of this study reveal that the removal of the AA5083 matrix by the impinging silicon carbide particles acts as the primary wear mechanism leading to the degradation of the coating. Analysis of the wear scar has demonstrated that the damage to the soft matrix alloy takes the form of ploughing and scoring which subsequently exposes carbide/oxide particles to the impinging slurry.

  10. Method of producing carbon coated nano- and micron-scale particles

    Science.gov (United States)

    Perry, W. Lee; Weigle, John C; Phillips, Jonathan

    2013-12-17

    A method of making carbon-coated nano- or micron-scale particles comprising entraining particles in an aerosol gas, providing a carbon-containing gas, providing a plasma gas, mixing the aerosol gas, the carbon-containing gas, and the plasma gas proximate a torch, bombarding the mixed gases with microwaves, and collecting resulting carbon-coated nano- or micron-scale particles.

  11. ELECTRICAL FURNACE FOR PRODUCING CARBIDE COATINGS USING THE THERMOREACTIVE DEPOSITION/DIFFUSION TECHNIQUE

    Directory of Open Access Journals (Sweden)

    FABIO CASTILLEJO

    2011-01-01

    the presence of VC and NbC, and as MEB results clearly show, the formation of regular thickness coatings. The results obtained allow for assessing that the designed and built furnace fulfills the requirements of the TRD technique for obtaining different types of hard coatings.

  12. 超声波辅助制备非晶态Ni-Mo-B催化剂及其加氢脱氧性能研究%Influence of ultrasonic on the preparation of Ni-Mo-B amorphous catalyst and its performance in phenol hydrodeoxygenation

    Institute of Scientific and Technical Information of China (English)

    王威燕; 杨运泉; 罗和安; 包建国; 陈卓

    2009-01-01

    用普通方法和超声波法制备了非晶态Ni-Mo-B催化剂,用BET、SEM、XRD、XPS和FT-IR等手段对催化剂进行表征.以苯酚为探针考察了催化剂的制备因素和反应温度对催化剂加氢脱氧性能的影响,探讨了苯酚在非晶态Ni-Mo-B催化剂表面上的吸附加氢脱氧反应机理.结果表明,超声波条件下制备的催化剂粒径小,颗粒团聚减弱,比表面积大,MoO_2与B的含量高,催化剂活性高.在498K时,苯酚的转化率达81.08%,脱氧选择性达93.39%.

  13. X-ray residual stress measurement of laminated coating layers produced by plasma spraying

    Energy Technology Data Exchange (ETDEWEB)

    Nishida, Masayuki (Faculty of Engineering, Tokushima Univ. (Japan)); Hanabusa, Takao (Faculty of Engineering, Tokushima Univ. (Japan)); Fujiwara, Haruo (Faculty of Engineering, Tokushima Univ. (Japan))

    1993-12-03

    The present paper describes residual stress in laminated layers deposited by thermal spraying on a low carbon steel substrate. Laminated layers were made of Al[sub 2]O[sub 3]-NiCr or Al[sub 2]O[sub 3]-NiAl with various combinations of mixing ratios. X-Ray diffraction was used to measure residual stress in the outermost surface layer. The results of finite-element method (FEM) thermal stress analysis were compared with the experimental results of X-ray measurements. From the X-ray stress measurements, tensile residual stress (100-300 MPa) was measured in the as-coated surface layers of all specimens. The effect of annealing on residual stress variation was also examined. In the case of the Al[sub 2]O[sub 3] (100%) layer of the Al[sub 2]O[sub 3]-NiCr system, residual stress of surface layers was not greatly affected by the method of lamination and did not change significantly upon annealing. In contrast, in the layer with mixed Al[sub 2]O[sub 3] and NiAl, residual stress in the as-coated layer was influenced by the mixing ratio of Al[sub 2]O[sub 3] and NiAl. Furthermore, residual stresses were gradually reduced in both the Al[sub 2]O[sub 3] and Ni phase following annealing. FEM calculation revealed that large compressive residual stress (about -2 GPa) was produced in the 100% Al[sub 2]O[sub 3] layer after a full annealing treatment. The value of residual stress depends on the difference between the thermal expansion coefficients of the laminated layers and the substrate. This result was exactly opposite to the experimental results for the fully annealed Al[sub 2]O[sub 3]-NiCr system. However, residual stresses in the mixed layer (Al[sub 2]O[sub 3]-NiAl) depended on the mixing ration of Al[sub 2]O[sub 3] and NiAl. This agrees qualitatively with the experimental results. (orig.)

  14. Automated coating procedures to produce poly(ethylene glycol) brushes in fused-silica capillaries

    DEFF Research Database (Denmark)

    Poulsen, Nicklas N.; Østergaard, Jesper; Petersen, Nickolaj J.

    2017-01-01

    . Flexible and reliable approaches for preventing unwanted protein adsorption in separation science are thus in high demand. We therefore present new coating approaches based on an automated in-capillary surface initiated atom transfer radical polymerization process (covalent coating) as well...... as by electrostatically adsorbing a pre-synthesized polymer leading to functionalized molecular brushes. The electroosmotic flow was measured following each step of the covalent coating procedure providing a detailed characterization and quality control. Both approaches resulted in good fouling resistance against...... the four model proteins cytochrome c, myoglobin, ovalbumin and human serum albumin in the pH range 3.4-8.4. Further, even samples containing 10% v/v plasma derived from human blood did not show signs of adsorbing to the coated capillaries. The covalent as well as the electrostatically adsorbed coating were...

  15. Microstructure Characterization of WCCo-Mo Based Coatings Produced Using High Velocity Oxygen Fuel

    Directory of Open Access Journals (Sweden)

    Serkan Islak

    2015-12-01

    Full Text Available The present study has been carried out in order to investigate the microstructural properties of WCCo-Mo composite coatings deposited onto a SAE 4140 steel substrate by high velocity oxygen fuel (HVOF thermal spray. For this purpose, the Mo quantity added to the WCCo was changed as 10, 20, 30 and 40 wt. % percents. The coatings are compared in terms of their phase composition, microstructure and hardness. Phase compound and microstructure of coating layers were examined using X-ray diffractometer (XRD and scanning electron microscope (SEM. XRD results showed that WCCo-Mo composite coatings were mainly composed of WC, W2C, Co3W3C, Mo2C, MoO2, Mo and Co phases. The average hardness of the coatings increased with increasing Mo content.

  16. Microstructures and Composition of Ceramic Coatings on Aluminum Produced by Micro-Arc Oxidation

    Institute of Scientific and Technical Information of China (English)

    SHEN De-jiu; WANG Yu-lin; GU Wei-chao; XING Guang-zhong

    2004-01-01

    Microstructures and phase composition of the ceramic coatings formed on pure aluminum by heteropolar pulsed current ceramic synthesizing system for different periods were investigated by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). Results show that the amount of the discharge channels in the ceramic coating sminish while the aperture largen in the micro-arc oxidation process, and the surface of the ceramic coatingmelted and solidified in the process.XRD studies of ceramic coatings deposited for different time show that these coatings consist mainly of α-Al2 O3, γ-Al2 O3 , θ-Al2 O3 and a little amorphous phase, and phase composition of compact and porous ceramic coatings don' t have much difference but have a little change of the content of α-Al2 O3 and amorphous phase.

  17. COMPARISON OF THERMAL SHOCK BEHAVIOR OF 7YSZ, 15YSZ AND SYSZ THERMAL BARRIER COATINGS PRODUCED BY APS METHOD

    Directory of Open Access Journals (Sweden)

    H. Jamali

    2016-07-01

    Full Text Available Nanostructured scandia, yttria doped zirconia (SYSZ, 7wt. % yttria stabilized zirconia (7YSZ and 15YSZ thermal barrier coatings (TBCs were produced by plasma spraying on nickel-based superalloy substrates with NiCrAlY as the bond coat. The thermal shock behavior of the three as-sprayed TBCs at 1000 °C was investigated. The results indicated that the thermal cycling lifetime of SYSZ and 7YSZ TBCs was longer than the 15YSZ TBCs due to the lower thermal mismatch stress between the ceramic layer and the metallic layer at high temperature and higher amount of tetragonal phase.

  18. Magnesium substituted hydroxyapatite formation on (Ti,Mg)N coatings produced by cathodic arc PVD technique

    Energy Technology Data Exchange (ETDEWEB)

    Onder, Sakip [Department of Metallurgical and Materials Engineering, Istanbul Technical University, 34469, Maslak, Istanbul (Turkey); Molecular Biology-Genetics and Biotechnology Program (MOBGAM), Istanbul Technical University, 34469, Maslak, Istanbul (Turkey); Kok, Fatma Nese [Molecular Biology-Genetics and Biotechnology Program (MOBGAM), Istanbul Technical University, 34469, Maslak, Istanbul (Turkey); Department of Molecular Biology and Genetics, Istanbul Technical University, 34469, Maslak, Istanbul (Turkey); Kazmanli, Kursat, E-mail: kursat@itu.edu.tr [Department of Metallurgical and Materials Engineering, Istanbul Technical University, 34469, Maslak, Istanbul (Turkey); Urgen, Mustafa [Department of Metallurgical and Materials Engineering, Istanbul Technical University, 34469, Maslak, Istanbul (Turkey)

    2013-10-15

    In this study, formation of magnesium substituted hydroxyapatite (Ca{sub 10−x}Mg{sub x}(PO{sub 4}){sub 6}(OH){sub 2}) on (Ti,Mg)N and TiN coating surfaces were investigated. The (Ti{sub 1−x},Mg{sub x})N (x = 0.064) coatings were deposited on titanium substrates by using cathodic arc physical vapor deposition technique. TiN coated grade 2 titanium substrates were used as reference to understand the role of magnesium on hydroxyapatite (HA) formation. The HA formation experiments was carried out in simulated body fluids (SBF) with three different concentrations (1X SBF, 5X SBF and 5X SBF without magnesium ions) at 37 °C. The coatings and hydroxyapatite films formed were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) and FTIR Spectroscopy techniques. The energy dispersive X-ray spectroscopy (EDS) analyses and XRD investigations of the coatings indicated that magnesium was incorporated in the TiN structure rather than forming a separate phase. The comparison between the TiN and (Ti, Mg)N coatings showed that the presence of magnesium in TiN structure facilitated magnesium substituted HA formation on the surface. The (Ti,Mg)N coatings can potentially be used to accelerate the HA formation in vivo conditions without any prior hydroxyapatite coating procedure. - Highlights: • Mg incorporated in (Ti,Mg)N coating structure and did not form a separate phase • Mg dissolution in SBF solution facilitated Mg-substituted hydroxyapatite formation • (Ti,Mg)N acted as Mg-source for Mg-substituted hydroxyapatite formation in SBF.

  19. Structure and properties of protective coatings produced by vacuum arc deposition

    Energy Technology Data Exchange (ETDEWEB)

    Leontiev, S.A. [Leningradsky Metallitchesky Zavod, St. Petersburg (Russian Federation); Kuznetsov, V.G. [Machine Research Problems Institute, Russian Academy of Sciences V.O., Bolshoy pr. 61, 199178 St. Petersburg (Russian Federation); Rybnikov, A.I. [Polzunov Central Boiler and Turbine Institute (NPO TsKTI), Polytechnicheskaya 24, 194021 St. Petersburg (Russian Federation); Burov, I.V. [Machine Research Problems Institute, Russian Academy of Sciences V.O., Bolshoy pr. 61, 199178 St. Petersburg (Russian Federation)

    1995-11-01

    CoCrAlY, NiCrWTi and CoCrAlY/ZrO{sub 2}+8wt.%Y{sub 2}O{sub 3} coatings were deposited by vacuum arc evaporation. Coatings were deposited onto specimens for metallographic analysis, corrosion resistance testing, thermal fatigue testing, high-frequency fatigue and onto gas turbine blades. It has been shown by testing that the developed procedures ensure gas turbine blade coatings of high quality comparable with those manufactured by electron beam procedures. (orig.)

  20. Characterization of nanostructured Ti-B-(N) coatings produced by direct current magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Cartes, C. [Instituto de Ciencia de Materiales de Sevilla (CSIC-Univ. Sevilla), Avda. Americo Vespucio 49, 41092 Sevilla (Spain)]. E-mail: clopez@icmse.csic.es; Martinez-Martinez, D. [Instituto de Ciencia de Materiales de Sevilla (CSIC-Univ. Sevilla), Avda. Americo Vespucio 49, 41092 Sevilla (Spain); Sanchez-Lopez, J.C. [Instituto de Ciencia de Materiales de Sevilla (CSIC-Univ. Sevilla), Avda. Americo Vespucio 49, 41092 Sevilla (Spain); Fernandez, A. [Instituto de Ciencia de Materiales de Sevilla (CSIC-Univ. Sevilla), Avda. Americo Vespucio 49, 41092 Sevilla (Spain); Garcia-Luis, A. [Fundacion INASMET, Mikeletegi Pasealekua 2, 20009 Donostia-San Sebastian (Spain); Brizuela, M. [Fundacion INASMET, Mikeletegi Pasealekua 2, 20009 Donostia-San Sebastian (Spain); Onate, J.I. [Fundacion INASMET, Mikeletegi Pasealekua 2, 20009 Donostia-San Sebastian (Spain)

    2007-02-26

    A series of Ti-B-(N) coatings prepared by dc magnetron sputtering using TiB{sub 2} targets in Ar/N{sub 2} gas mixtures has been chemically and structurally characterized by transmission electron microscopy, X-ray diffraction, electron energy-loss spectroscopy, and X-ray photoelectron spectroscopy. The influence of synthesis parameters such as applied heating power and nitrogen flow on the structure and chemical composition of the coatings has been studied. Independently of the experimental conditions employed during the synthesis, hexagonal TiB{sub 2} is the main crystalline phase present in the coatings. The use of N{sub 2} leads to the formation of an amorphous mixture of BN/TiN phases, as well as a diminution of the TiB{sub 2} crystalline phase. The influence of the composition and structure of the coatings on their hardness is also discussed.

  1. Investigation of Ni-Cr-Si-Fe-B coatings produced by the electron beam cladding technique

    Science.gov (United States)

    Zimogliadova, T. A.; Drobyaz, E. A.; Golkovskii, M. G.; Bataev, V. A.; Durakov, V. G.; Cherkasova, N. Yu

    2016-11-01

    This paper presents the results of structural investigations and results of tribological and microhardness tests of the coating obtained by electron beam cladding of a Ni-Cr-Si-Fe-B self-fluxing alloy on low-carbon steel. After electron beam treatment high-quality dense layer with a thickness of 1.2-1.8 mm was obtained. The structure of the coating consisted of dendrite crystals based on y-Ni-solid solution and eutectic with complex composition. Microhardness of the coating achieves 370 HV. Wear-resistance of the coating obtained by electron-beam cladding technique was 1.6-fold higher than that of low-carbon carburized steel.

  2. Effect of Boron on Microstructure and Microhardness Properties of Mo-Si-B Based Coatings Produced Via TIG Process

    Directory of Open Access Journals (Sweden)

    Islak S.

    2016-09-01

    Full Text Available In this study, Mo-Si-B based coatings were produced using tungsten inert gas (TIG process on the medium carbon steel because the physical, chemical, and mechanical properties of these alloys are particularly favourable for high-temperature structural applications. It is aimed to investigate of microstructure and microhardness properties of Mo-Si-B based coatings. Optical microscopy (OM, X-ray diffraction (XRD and scanning electron microscopy (SEM were used to characterize the microstructures of Mo-Si-B based coatings. The XRD results showed that microstructure of Mo–Si–B coating consists of α-Mo, α-Fe, Mo2B, Mo3Si and Mo5SiB2 phases. It was reported that the grains in the microstructure were finer with increasing amounts of boron which caused to occur phase precipitations in the grain boundary. Besides, the average microhardness of coatings changed between 735 HV0.3 and 1140 HV0.3 depending on boron content.

  3. Studies on Characterization of Sulfided Tertiary NiMoP/γ-Al2O3 Catalysts by TPR Technique and Their Thiophene HDS Activity%硫化态三组元NiMoP/γ-Al2O3催化剂的TPR表征及噻吩HDS活性的研究

    Institute of Scientific and Technical Information of China (English)

    齐兴义; 徐春明; 刘植昌; 李文钊; 辛勤

    2001-01-01

    A series of sulfided tertiary NiMoP/γ-Al2O3 catalysts with different contents of MoO3 were prepared by using molybdophosphoric acid of Keggin structure(H3PMo12O40) and nickel nitrate as origins of active phase components of molybdenum, phosphorus and nickel, and characterized by TPR technique, with their HDS activity being investigated with thiophene as a model substrate. For the sulfided Mo-0 catalyst containing no nickel as promoter, the only hydrogen sulfide evolution peak Ⅰ is observed at 462 K and attributed to the hydrogenation of the so-called edge sulfur atoms chemisorbed on coordinatively unsaturated(cus) Mox+ sites on the MoS2 phase(MoS2 slab). With the introduction of nickel into the active phase of the sulfided Mo-0 catalyst and with the increase of the molybdenum loading, a new hydrogen sulfide evolution peak Ⅱ gradually develops at the low temperature side of the peak Ⅰ, at the same time accompanied by both the increase of the area ratio of the peak Ⅱ to the peak Ⅰ and the shift of the hydrogen sulfide evolution maximum rate to lower temperatures, which may imply the existence of two kinds of active centers related to molybdenum and nickel respectively and the synergic action between the two centers above. It should be noted that for the sulfided NiMoP/γ-Al2O3 catalysts, the thiophene HDS rate and the quantity of hydrogen sulfide evolved during TPR process increase monotonously with the atomic ratio of molybdenum to nickel in the form of [n(Ni)+n(Mo)]/n(Ni). On the basis of the results here, the conclusion may be reached that the two kinds of vacancies can be formed on the edge of Ni-Mo-S slab due to the loss of S during TPR process and vacancies or sites related to the H2S evolution peak II should be regarded as the mainly active reaction centers of thiophene HDS.

  4. Oxidation performance of Fe-Al/WC composite coatings produced by high velocity arc spraying

    Institute of Scientific and Technical Information of China (English)

    MENG Fan-jun; XU Bin-shi; ZHU Sheng; MA Shi-ning; ZHANG wei

    2005-01-01

    Fe-Al intermetallics with remarkable high-temperature intensity and excellent erosion, high-temperature oxidation and sulfuration resistance are potential low cost high-temperature structural materials. But the room tem perature brittleness induces shape difficult and limits its industrial application. The Fe-Al intermetallic coatings were prepared by high velocity arc spraying technology with cored wire on 20G steel, which will not only obviate the problems faced in fabrication of these alloys into useful shapes, but also allow the effective use of their outstanding high-temperature performance. The Fe-Al/WC intermetallic composite coatings were prepared by high velocity arc spraying technology on 20G steel and the oxidation performance of Fe-Al/WC composite coatings was studied by means of thermogrativmetic analyzer at 450, 650 and 800 ℃. The results demonstrate that the kinetics curve of oxidation at three temperatures approximately follows the logarithmic law. The composition of the oxidized coating is mainly composed of Al2 O3, Fe2 O3, Fe3 O4 and FeO. These phases distribute unevenly. The protective Al2 O3 film firstly forms and preserves the coatings from further oxidation.

  5. Impact strength of GX8CrNi12, GX5CrNi18-9 and GX5CrNiMo19-11-2 cast steel at - 30 °C

    Directory of Open Access Journals (Sweden)

    B. Kalandyk

    2016-10-01

    Full Text Available The results of impact tests carried out at - 30 °C on cast alloyed GX8CrNi12, GX5CrNi18-9 and GX5CrNiMo19-11-2 steel grades are reported. It has been shown that at - 30 °C, the addition of 1 % Ni to cast GX8CrNi12 steel does not provide the required impact strength of 35 J/cm2. In contrast, other tested materials containing 8 ÷ 9 % Ni can easily reach exceeding 50 J/cm2. Numerous non-metallic inclusions present in the microstructure of cast GX5CrNi-Mo19-11-2 steel resulting from, among others, the miscalculated refining process were found to be one of the main causes of reduced impact strength as compared to the cast GX5CrNi18-9 steel.

  6. Sol-gel coatings: An alternative route for producing planar optical waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Rey-Garcia, F.; Gomez-Reino, C. [Unidad Asociada de Optica and Microoptica GRIN (CSIC-ICMA), Departamento de Fisica Aplicada, Escola Universitaria de Optica e Optometria, Universidade de Santiago de Compostela, Campus Sur s/n, E-15782 Santiago de Compostela (Spain); Flores-Arias, M.T., E-mail: maite.flores@usc.es [Unidad Asociada de Optica and Microoptica GRIN (CSIC-ICMA), Departamento de Fisica Aplicada, Escola Universitaria de Optica e Optometria, Universidade de Santiago de Compostela, Campus Sur s/n, E-15782 Santiago de Compostela (Spain); De La Fuente, G.F., E-mail: xerman@unizar.es [Instituto de Ciencia de Materiales de Aragon (CSIC-Universidad de Zaragoza), Maria de Luna 3, E-50018 Zaragoza (Spain); Duran, A. [Instituto de Ceramica y Vidrio (CSIC), Kelsen 5, E-28049, Madrid (Spain); Castro, Y., E-mail: castro@icv.csic.es [Instituto de Ceramica y Vidrio (CSIC), Kelsen 5, E-28049, Madrid (Spain)

    2011-09-01

    Inorganic and hybrid planar waveguides with different compositions (silica-titania, methacrylate-silica-cerium oxide, zirconia-cerium oxide and silica-zirconia) have been obtained by sol-gel synthesis followed by dip-coating. Soda-lime glass slides and conventional commercial window glass were used as substrates. The thickness and refractive index of the coatings were determined by profilometry and Spectroscopic Ellipsometry. Waveguide efficiency was measured at ca. 70.8% with a He-Ne laser beam, coupled with an optical microscope objective into and out of the waveguiding layer via a double prism configuration. Thicknesses between 150 and 2000 nm, along with refractive index values ranging between 1.45 and {approx} 1.99 ({lambda} = 633 nm) were obtained depending on the sol composition and the dip-coating conditions. This wide range of values allows designing multilayered guides that can be used in a variety of applications.

  7. Microanalyses of the hydroxyl—poly—calcium sodium phosphate coatings produced by ion beam assisted deposition

    Institute of Scientific and Technical Information of China (English)

    LIUZhong-Yang; WANGChang-Xing; 等

    2002-01-01

    Thin calcium phosphate catings on titanium alloy substrates were prepared by Ar+ ion beam assisted deposition(IBAD) from hydroxyl-poly-calcium sodium phosphate(HPPA) target.The coatings were analyzed by XRD,FTIR,XPS,These analyses revealed that the as-deposited films were amorphous or no apparent crystallinity.No distinct absorption band of the hydroxyl group was observed in FTIR spectra of the coatings but new absorption bands were presented for CO3-2,The calcium to phosphorous ratio of these catings in different IBAD conditions varied from 0.46 to 3.36.

  8. Assembly of flexible CoMoO4@NiMoO4·xH2O and Fe2O3 electrodes for solid-state asymmetric supercapacitors

    Science.gov (United States)

    Wang, Jing; Zhang, Leipeng; Liu, Xusong; Zhang, Xiang; Tian, Yanlong; Liu, Xiaoxu; Zhao, Jiupeng; Li, Yao

    2017-01-01

    In this work, CoMoO4@NiMoO4·xH2O core-shell heterostructure electrode is directly grown on carbon fabric (CF) via a feasible hydrothermal procedure with CoMoO4 nanowires (NWs) as the core and NiMoO4 nanosheets (NSs) as the shell. This core-shell heterostructure could provide fast ion and electron transfer, a large number of active sites, and good strain accommodation. As a result, the CoMoO4@NiMoO4·xH2O electrode yields high-capacitance performance with a high specific capacitance of 1582 F g−1, good cycling stability with the capacitance retention of 97.1% after 3000 cycles and good rate capability. The electrode also shows excellent mechanical flexibility. Also, a flexible Fe2O3 nanorods/CF electrode with enhanced electrochemical performance was prepared. A solid-state asymmetric supercapacitor device is successfully fabricated by using flexible CoMoO4@NiMoO4·xH2O as the positive electrode and Fe2O3 as the negative electrode. The asymmetric supercapacitor with a maximum voltage of 1.6 V demonstrates high specific energy (41.8 Wh kg−1 at 700 W kg−1), high power density (12000 W kg−1 at 26.7 Wh kg−1), and excellent cycle ability with the capacitance retention of 89.3% after 5000 cycles (at the current density of 3A g−1). PMID:28106170

  9. NiMo/Al2O3 catalyst containing nano-sized zeolite Y for deep hydrodesulfurization and hydrodenitrogenation of diesel

    Institute of Scientific and Technical Information of China (English)

    Hailiang Yin; Tongna Zhou; Yunqi Liu; Yongming Chai; Chenguang Liu

    2011-01-01

    Two mixed-matrix NiMo/Al2O3 catalysts containing nano- and micro-sized zeolite Y have been prepared to explore the size effect of zeolite Y particle on the hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) activities of fluid catalytic cracking (FCC) diesel.They were characterized by SEM,BET,XRD,H2-TPR,NH3-TPD and HRTEM.The results show that the catalyst containing nano-sized zeolite Y possesses larger average pore diameter,higher pore volume,weaker and lesser acid sites,more easily reducible metal phases,shorter MoS2 slabs and more slab layers than the catalyst containing micro-sized zeolite Y.The catalysts were also evaluated with a high-pressure fixed-bed reactor using real FCC diesel as feed.The results display that the catalyst containing nano-sized zeolite Y bears higher HDS and HDN activities and exhibits higher relative rate constant for the removal of total sulfur or nitrogen than the one containing micro-sized zeolite.

  10. Influence of Ni/Mo ratio on structural and electrical properties of double perovskite system Sr2Ni1+ x Mo1- x O6- δ

    Science.gov (United States)

    Kumar, Pravin; Singh, Nitish Kumar; Singh, Rajesh Kumar; Singh, Prabhakar

    2015-11-01

    Technologically important double perovskite system Sr2Ni1+ x Mo1- x O6- δ with x = 0.00, 0.05, 0.10, and 0.15 was prepared by solution combustion method. The structural and the Rietveld analysis of compositions revealed the formation of double perovskite tetragonal phase Sr2NiMoO6 with space group I4/m as a major phase. SrMoO4 and NiO were also observed as minor phases. Microstructural studies depicted the formation of uniform grains for all the samples. The average grain size was found to lie between the ranges of 1-4 μm. XPS analysis of the synthesized compositions showed the decreasing ratio of Mo5+ to Mo6+ ions in the system with increasing Ni content, which played an important role in the conduction mechanism. The thermal expansion coefficient (TEC) of all compositions indicated that it is more compatible to the TEC of standard electrolytes. The electrical conductivity for all the compositions was studied using impedance spectroscopy in the temperature range 200-600 °C. Composition with x = 0.05 showed better electrical conductivity with good catalytic activity.

  11. Structural and electrical characterizations of cerium (Ce{sup 3+})-doped double perovskite system Sr{sub 2}NiMoO{sub 6-δ}

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Pravin; Singh, Nitish Kumar; Singh, Prabhakar [Indian Institute of Technology (BHU), Department of Physics, Varanasi (India); Sinha, A.S.K. [Indian Institute of Technology (BHU), Department of Chemical Engineering and Technology, Varanasi (India)

    2016-09-15

    The double perovskite system Sr{sub 2-x} Ce{sub x} NiMoO{sub 6-δ} (SCNM) with 0.01 ≤ x ≤ 0.05 was synthesized by the citrate-nitrate auto-combustion synthesis route. Thermal studies were carried out by simultaneous differential scanning calorimetry and thermal gravimetry. Phase constitution was analyzed by powder X-ray diffraction (XRD). Rietveld refinement showed that the major phase exists in tetragonal form with space group I4/m. Microstructural investigations revealed the formation of uniform grains. The electrical conductivity studied by impedance spectroscopy in the temperature range 300-600 C was found to follow a thermally activated process. The sample with x = 0.01 showed the highest conductivity with lowest activation energy. The electrical conductivity of the system was discussed in terms of identified impurity phases and charge density [Mo{sup 5+}{sub Mo}{sup {sub 6}{sub +}}']. The variation of electrical conductivity with composition was explained on the basis of X-ray photoelectron spectroscopy and XRD studies. (orig.)

  12. Low porosity and fine coatings produced by a new type nozzle of high velocity arc spray gun

    Institute of Scientific and Technical Information of China (English)

    Wang Ruijun; Zhang Tianjian; Xu Lin; Huang Xiaoou

    2006-01-01

    The new designed high-velocity arc spray gun with three different nozzles is developed to match the DZ400 arc spray system, which can produce the coatings with the structure of superfine and low porosity.This system can be used to spray three normal wires such as 4Cr13, FeCrAl and 7Cr13 (flux cored wires).Using the scanning electron microscope (SEM) to analyze shape and particles size that sprayed by the nozzles with different parameters, as well as with the S-3500N SEM and the energy spectrum analytic ( ESA ) instrument to identify the content of the oxides, porosity and thickness of the coatings, we get the result that the porosity in the coatings of solid wire is less than 3%, of the flux-cored wires is less than 5%, and the distribution of the coatings sprayed by the nozzle with secondary supplementary airflow is typically shown in the form of highdensity lamellarsplat structure and the average lamellar thickness is around 5 μm.

  13. Microstructure characteristics of ZrO2 coating produced by atmospheric pressure chemical vapor deposition.

    Science.gov (United States)

    Sun, Wei; Xiong, Xiang; Li, Xiaobin

    2011-09-01

    To settle the problem of low growth rate when prepare ZrO2 thermal barrier coating by Metalorganic CVD (MOCVD), a simple method was employed-atmospheric pressure CVD (APCVD). The paper firstly thermodynamic calculated the effect of O/Zr ratio and temperature on phase formation at various H/C ratios for ZrCl4-CO2-H2-Ar system. With temperature increment, the solid phase changes from C+ monoclinic ZrO2 to Monoclinic ZrO2 then to tetragonal ZrO2. With the increase of H/C ratio, the phase zone of C+ monoclinic ZrO2 expands. XRD and Raman spectrum were employed to measure phase structure of ZrO2 coating at different temperature. At 1300 degrees C, the coating contains a small amount tetragonal ZrO2 phase besides monoclinic phase; at 1100 degrees C, the coating is composed of monoclinic ZrO2 phase and a little C. The surface SEM images show the small grains evolve to polycrystals which have clear crystal form when raising temperature. The cross-section images show that dense ZrO2 column crystals arrange normal to the substrate.

  14. Thick metallic coatings produced by coaxial and side laser cladding : Processing and properties

    NARCIS (Netherlands)

    Ocelík, V.; De Hosson, J.T.M.

    2010-01-01

    Cobalt and iron-based, defect-free coatings with thicknesses from 1 to 3.3. mm were created by a laser cladding process on different steel substrates. Extensive laser cladding experiments with a gradual change of laser power were used to study relations between main processing parameters and geometr

  15. Kinetics of niobium carbide coating produced on AISI 1040 steel by thermo-reactive deposition technique

    Energy Technology Data Exchange (ETDEWEB)

    Sen, Ugur

    2004-07-15

    There are a lot of technologically interesting characteristics of niobium carbide coating deposited by pack method which is the production of hard, wear-resistant, oxidation and corrosion resistant coating layer on the steel substrates. In the present study, the growth kinetics of niobium carbide layer deposited by thermo-reactive diffusion techniques in a solid medium on steel samples was reported. Niobium carbide coating treatment was performed on AISI 1040 steels in the powder mixture consisting of ferro-niobium, ammonium chloride and alumina at 1073, 1173 and 1273 K for 1-4 h. The presence of NbC and Nb{sub 2}C phases formed on the surface of the steel substrates was confirmed by optical microscopy, scanning electron microscopy (SEM) and X-ray diffraction analyses. Niobium carbide layer thickness ranges from 3.42{+-}0.52 to 11.78{+-}2.29 {mu}m depending upon the treatment time and temperature. Layer growth kinetics was analyzed by measuring the depth of niobium carbide layer as a function of time and temperature. The kinetics of niobium carbide coating by pack method shows a parabolic relationship between carbide layer thickness and treatment time, and the activation energy for the process is estimated to be 91.257 kJ mol{sup -1}. Moreover, an attempt was made to investigate the possibility of predicting the contour diagram of niobium carbide layer variation and to establish some empirical relationships between process parameters and niobium carbide layer thickness.

  16. Research on tests and numerical analysis of corrosion and wear damage of mooring chain steel 22MnCrNiMo%海洋系泊链钢22MnCrNiMo 腐蚀磨损试验与数值分析研究

    Institute of Scientific and Technical Information of China (English)

    粟京; 刘刚; 孙佳君

    2015-01-01

    A numerical analysis method is proposed to calculate accumulative damages of corrosion and wear of chain link in service period.Both the corrosion of chain annulus in seawater environment and the wear of contact surface between adjacent links can be considered by using non-linear finite element analy-sis.For determining mechanical properties of the chain steel used in the finite element analysis,mechani-cal tests with the low-carbon and low-alloy steel 22MnCrNiMo are carried out to obtain its material hard-ness,seawater erosion and corrosion wear resistance.Numerical results and experimental data are com-pared to verify the feasibility and accuracy of the proposed method.%建立了锚链在海洋环境中腐蚀磨损(简称“磨蚀”)累积损伤数值分析方法,该方法采用非线性有限元分析,能够同时考虑锚链链环间接触面在海水中的腐蚀和磨损耦合损伤。针对22MnCrNiMo 低碳低合金钢材料,进行了力学性能、海水侵蚀以及磨蚀性能等多方面的试验研究,确定了基于该材料的锚链链环间接触面在海水中磨蚀损伤数值分析中的相关参数。通过对计算结果与试验结果的比较分析,验证了锚链链环间接触面磨蚀累积损伤数值分析方法的可行性与准确性。

  17. Some preliminary evaluations of black coating on aluminium AA2219 alloy produced by plasma electrolytic oxidation (PEO) process for space applications

    Science.gov (United States)

    Shrestha, S.; Merstallinger, A.; Sickert, D.; Dunn, B. D.

    2003-09-01

    This paper describes the results of a study of a black coating produced on aluminium AA2219 alloy using a process that involves creation of a hard ceramic oxide layer on the surface of the alloy by plasma electrolytic oxidation (PEO) known as the 'KERONITE®' process. Coating microstructure has been examined and the coating characteristics such as porosity, hardness, adhesion and phase composition were measured. The thermo-optical properties such as solar absorptance 'as' and normal infrared emittance 'en-IR' of the coating were measured in the 'as-prepared' condition and after environmental exposures to humidity, thermal cycling and UV-radiation in vacuum and to thermal shock. Comparison was made with alternative coatings produced using standard black anodising processes. The study also looked at the cold welding and friction behaviours of the coated alloy in vacuum and in an ambient laboratory environment. Standard spacecraft materials tests were conducted on the coated disc against an AISI 52100 steel ball and also against a coated pin using a pin-on-disc apparatus. Parameters such as friction coefficient and wear depth were measured and the cold welding behaviours were investigated. Test results were compared with the data generated for NiCr plated and anodised coatings. Corrosion performance was assessed using a salt spray exposure test and using an accelerated electrochemical test method. In addition, the study looked at the effect of post coating sealing with a sol-gel solution.

  18. Cutting performance and wear mechanisms of PVD coated carbide tools during dry drilling of newly produced ADI

    Science.gov (United States)

    Meena, Anil; El Mansori, Mohamed

    2016-10-01

    The austempered ductile iron (ADI) material is widely used for automotive and structural applications. However, it is considered a difficult to machine material due to its strain hardening behavior and low thermal conductivity characteristics; thus delivering higher mechanical and thermal loads at the tool-chip interface, which significantly affects the tool wear and surface quality. The paper thus overviews the cutting performance and wear behavior of different cutting tools during dry drilling of newly produced ADI material. Cutting performance was evaluated in terms of specific cutting energy, workpiece surface integrity and tool wear behavior. Tool wear behavior shows crater wear mode and workpiece adhesion. The surface alteration at the machined subsurface was confirmed from the hardness variation. Multilayer (Ti,Al,Cr)N coated tool shows improved cutting performance and wear behavior due to its enhanced tribological adaptability as compared to another PVD coating leading to the reduction in specific cutting energy by 25%.

  19. Kinetics and mechanism of desulfurization and denitrogenation of coal-derived liquids. Third quarterly report, December 20, 1975--March 20, 1976. [13 refs. ; dibenzothiophene; Ni-Mo/Al/sub 2/O/sub 3/; Ni-W/Al/sub 2/O/sub 3/; Ni-W/Al/sub 2/O/sub 3/-SiO/sub 2/; Co-Mo/Al/sub 2/O/sub 3/

    Energy Technology Data Exchange (ETDEWEB)

    Katzer, J. R.; Gates, B. C.; Olson, J. H.; Kwart, H.; Stiles, A. B.

    1976-04-20

    The high-pressure liquid-phase flow microreactor is a unique reactor for obtaining quantitative kinetic data for catalytic hydrodesulfurization and hydrodenitrogenation. The hydrodesulfurization of dibenzothiophene involves formation of biphenyl as a primary reaction product without hydrogenation of the aromatic rings. The catalytic hydrodenitrogenation of quinoline involves rapid hydrogenation of the nitrogen-containing ring followed by cracking of the ring to produce an aniline which is slowly hydrodenitrogenated. The hydrodenitrogenation reactions follow first-order kinetics. The order of activity of five commercial hydrotreating catalysts for quinoline hydrodenitrogenation is (Ni--Mo/Al/sub 2/O/sub 3/) > (Ni--W/Al/sub 2/O/sub 3/) > (Ni--W/Al/sub 2/O/sub 3/--SiO/sub 2/) > (Co--Mo/Al/sub 2/O/sub 3/).

  20. Compositions of corrosion-resistant Fe-based amorphous metals suitable for producing thermal spray coatings

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, Joseph C.; Wong, Frank M. G.; Haslam, Jeffery J.; Ji, Xiaoyan (Jane); Day, Sumner D.; Blue, Craig A.; Rivard, John D. K.; Aprigliano, Louis F.; Kohler, Leslie K.; Bayles, Robert; Lemieux, Edward J.; Yang, Nancy; Perepezko, John H.; Kaufman, Larry; Heuer, Arthur; Lavernia, Enrique J.

    2013-07-09

    A method of coating a surface comprising providing a source of amorphous metal that contains manganese (1 to 3 atomic %), yttrium (0.1 to 10 atomic %), and silicon (0.3 to 3.1 atomic %) in the range of composition given in parentheses; and that contains the following elements in the specified range of composition given in parentheses: chromium (15 to 20 atomic %), molybdenum (2 to 15 atomic %), tungsten (1 to 3 atomic %), boron (5 to 16 atomic %), carbon (3 to 16 atomic %), and the balance iron; and applying said amorphous metal to the surface by a spray.

  1. Compositions of corrosion-resistant Fe-based amorphous metals suitable for producing thermal spray coatings

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, Joseph C; Wong, Frank M.G.; Haslam, Jeffery J; Ji, Xiaoyan; Day, Sumner D; Blue, Craig A; Rivard, John D.K.; Aprigliano, Louis F; Kohler, Leslie K; Bayles, Robert; Lemieux, Edward J; Yang, Nancy; Perepezko, John H; Kaufman, Larry; Heuer, Arthur; Lavernia, Enrique J

    2013-09-03

    A method of coating a surface comprising providing a source of amorphous metal that contains manganese (1 to 3 atomic %), yttrium (0.1 to 10 atomic %), and silicon (0.3 to 3.1 atomic %) in the range of composition given in parentheses; and that contains the following elements in the specified range of composition given in parentheses: chromium (15 to 20 atomic %), molybdenum (2 to 15 atomic %), tungsten (1 to 3 atomic %), boron (5 to 16 atomic %), carbon (3 to 16 atomic %), and the balance iron; and applying said amorphous metal to the surface by a spray.

  2. Lubricated sliding wear behaviour of Ni-P-W multilayered alloy coatings produced by pulse plating

    DEFF Research Database (Denmark)

    Panagopoulos, C. N.; Papachristos, V. D.; Christoffersen, Lasse

    2000-01-01

    content. The wavelengths studied were 6, 200 and 2000 nm and the total thickness of the coatings was 25 mu m approximately. Using a range of normal loads between 2 and 110 N and a range of sliding speeds between 14 and 90 cm/s, the Stribeck curve of the system was constructed. indicating the various...... lubrication regimes. The wear mechanisms in each lubrication regime were studied and in mixed lubrication regime, the effect of normal load and sliding speed on wear volume and friction coefficient was also studied. (C) 2000 Elsevier Science S.A. All rights reserved....

  3. SiC-Si[sub 3]N[sub 4] composite coatings produced by plasma-enhanced chemical vapour deposition

    Energy Technology Data Exchange (ETDEWEB)

    Gerretsen, J. (Centre for Technical Ceramics, Netherlands Organization for Applied Scientific Research, Eindhoven (Netherlands)); Kirchner, G. (Centre for Technical Ceramics, Netherlands Organization for Applied Scientific Research, Eindhoven (Netherlands)); Kelly, T. (Irish Science and Technology Agency, Dublin (Ireland)); Mernagh, V. (Irish Science and Technology Agency, Dublin (Ireland)); Koekoek, R. (Tempress, Hoogeveen (Netherlands)); McDonnell, L. (Tekscan Ltd., Cork (Ireland))

    1993-10-08

    Silicon carbonitride coatings have been produced by plasma-enhanced chemical vapour deposition (CVD) on AISI 440C steel in a hot-wall reactor at 250 C from a mixture of SiH[sub 4], N[sub 2]-NH[sub 3] and C[sub 2]H[sub 4], and analysed by electron probe microanalysis and Rutherford backscattering spectroscopy-elastic recoil detection. Coatings with different ratios of silicon carbide to silicon nitride and silicon suband superstoichiometries have been deposited. Stoichiometric coatings show a maximum in their mechanical properties. Depending on the SiC-to-Si[sub 3]N[sub 4] ratio, the Knoop hardness values vary between 1500 and 2800 HK[sub 0.025]. Internal stress is low at a level of 100-300 MPa. The pinhole density is less than 2 cm[sup -2]. The fracture toughness as determined from indention tests is 4 MPa m[sup 1/2]. Linear polarization testing results show excellent protection of the substrate material against chemically aggressive media as compared with conventional CVD. (orig.)

  4. Soft-x-ray imaging from an ultrashort-pulse laser-produced plasma using a multilayer coated optic

    Science.gov (United States)

    Norby, J. R.; van Woerkom, L. D.

    1996-02-01

    Measurements are presented of soft-x-ray images from a plasma produced by a high-intensity ultrashort-pulse laser. For the intensity range of 1015-1016 W / cm2 the soft-x-ray source appears to follow the spatial profile of the driving laser. A curved multilayer coated optic is used to collect 13.5-nm light and form a magnified image of the plasma. Knife-edge scans have been performed in the image plane and show a geometrically limited spot size of 280 mu m.

  5. Single Layer Broadband Anti-Reflective Coatings for Plastic Substrates Produced by Full Wafer and Roll-to-Roll Step-and-Flash Nano-Imprint Lithography

    Directory of Open Access Journals (Sweden)

    Pascal Buskens

    2013-08-01

    Full Text Available Anti-reflective coatings (ARCs are used to lower the reflection of light on the surface of a substrate. Here, we demonstrate that the two main drawbacks of moth eye-structured ARCs—i.e., the lack of suitable coating materials and a process for large area, high volume applications—can be largely eliminated, paving the way for cost-efficient and large-scale production of durable moth eye-structured ARCs on polymer substrates. We prepared moth eye coatings on polymethylmethacrylate (PMMA and polycarbonate using wafer-by-wafer step-and-flash nano-imprint lithography (NIL. The reduction in reflection in the visible field achieved with these coatings was 3.5% and 4.0%, respectively. The adhesion of the coating to both substrates was good. The moth eye coating on PMMA demonstrated good performance in three prototypical accelerated ageing tests. The pencil hardness of the moth eye coatings on both substrates was <4B, which is less than required for most applications and needs further optimization. Additionally, we developed a roll-to-roll UV NIL pilot scale process and produced moth eye coatings on polyethylene terephthalate (PET at line speeds up to two meters per minute. The resulting coatings showed a good replication of the moth eye structures and, consequently, a lowering in reflection of the coated PET of 3.0%.

  6. Bone ingrowth potential of electron beam and selective laser melting produced trabecular-like implant surfaces with and without a biomimetic coating.

    Science.gov (United States)

    Biemond, J E; Hannink, G; Verdonschot, N; Buma, P

    2013-03-01

    The bone ingrowth potential of trabecular-like implant surfaces produced by either selective laser melting (SLM) or electron beam melting (EBM), with or without a biomimetic calciumphosphate coating, was examined in goats. For histological analysis and histomorphometry of bone ingrowth depth and bone implant contact specimens were implanted in the femoral condyle of goats. For mechanical push out tests to analyse mechanical implant fixation specimens were implanted in the iliac crest. The follow up periods were 4 (7 goats) and 15 weeks (7 goats). Both the SLM and EBM produced trabecular-like structures showed a variable bone ingrowth after 4 weeks. After 15 weeks good bone ingrowth was found in both implant types. Irrespective to the follow up period, and the presence of a coating, no histological differences in tissue reaction around SLM and EBM produced specimens was found. Histological no coating was detected at 4 and 15 weeks follow up. At both follow up periods the mechanical push out strength at the bone implant interface was significantly lower for the coated SLM specimens compared to the uncoated SLM specimens. The expected better ingrowth characteristics and mechanical fixation strength induced by the coating were not found. The lower mechanical strength of the coated specimens produced by SLM is a remarkable result, which might be influenced by the gross morphology of the specimens or the coating characteristics, indicating that further research is necessary.

  7. Microstructure and thermal conductivity of Cu/diamond composites with Ti-coated diamond particles produced by gas pressure infiltration

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jianwei; Zhang, Hailong; Zhang, Yang; Che, Zifan; Wang, Xitao, E-mail: xtwang@ustb.edu.cn

    2015-10-25

    As an attractive thermal management material, diamond particles reinforced Cu matrix (Cu/diamond) composites generally exhibit thermal conductivities lower than expected. To exploit the potential of heat conduction, a combination of Ti coating on diamond particles and gas pressure infiltration was used to prepare Cu/diamond(Ti) composites. A high thermal conductivity of 716 W/mK and a low coefficient of thermal expansion of 5.8 ppm/K at 323 K were obtained in the composites. Auger electron spectroscopy (AES) characterization shows that a TiC layer was formed between Cu matrix and diamond reinforcement, which is responsible for the enhancement of thermal conductivity. The results suggest that Ti coating can significantly promote interface bonding between Cu and diamond and gas pressure infiltration is an effective method to produce Cu/diamond composites. - Highlights: • The Cu/diamond(Ti) composites are produced by gas pressure infiltration. • A TiC layer is formed between Cu matrix and diamond reinforcement. • A thermal conductivity of 716 W/mK is obtained for the composites. • A coefficient of thermal expansion of 5.8 ppm/K at 323 K was obtained.

  8. Modelado Cinético y Evaluación de Catalizadores Mo2C, Mo2N y Ni-Mo/C en la Reacción de Hidrogenación de Lactosa Kinetic Modeling and Assessment of Mo2C, Mo2N and Ni-Mo/C Catalysts in the Hydrogenation Reaction of Lactose

    Directory of Open Access Journals (Sweden)

    Janine R. G Vieira

    2010-01-01

    Full Text Available El objetivo de este estudio fue evaluar los catalizadores Mo2C, Mo2N y Ni-Mo/C en la hidrogenación catalítica de lactosa para obtención de lactitol. Los experimentos de hidrogenación se realizaron en autoclave agitada mecánicamente a 500 rpm, 120 °C y 68 atm, utilizando una solución de lactosa comercial, solución de suero de queso bruto y solución de suero de queso tras adsorción de proteínas y de iones cloruros. El contenido de proteínas y de iones cloruros disminuyó, mediante coagulación con quitosana y desmineralización por cambio iónico, respectivamente. Además, se hicieron pruebas modificando el pH, en medio ácido (3.5 y básico (8. El mejor rendimiento en lactitol fue del 46% con Mo2C a pH 8. Los resultados obtenidos en los experimentos de hidrogenación se modelaron usando la cinética de Langmuir-Hinshelwoold. Los resultados experimentales de concentración de lactosa y lactitol concuerdan razonablemente bien con los previstos por el modelo.The purpose of this study was evaluating Mo2C, Mo2N and Ni-Mo/C catalyzers in the catalytic hydrogenation of lactose to obtain lactitol. Hydrogenation experiments were done at 120°C and 68 atm. in a batch autoclave using mechanical agitation at 500 rpm, with a solution of commercial lactose, serum solution of raw cheese and serum solution after protein and chloride ion adsorption. Protein and chloride ion levéis decreased through chitosan coagulation and ion exchange demineralization, respectively. Furthermore, the pH was also tested in acidic (3.5 and basic médium (8. The best lactitol yield was 46% with Mo2C at pH 8 using commercial lactitol. The hydrogenation results obtained in the experiments were modeled by the Langmuir-Hinshelwood kinetics. The experimental results of lactose and lactitol concentration were similar to those predicted by the model.

  9. Whole blood treated with riboflavin and ultraviolet light: quality assessment of all blood components produced by the buffy coat method.

    Science.gov (United States)

    Schubert, Peter; Culibrk, Brankica; Karwal, Simrath; Serrano, Katherine; Levin, Elena; Bu, Daniel; Bhakta, Varsha; Sheffield, William P; Goodrich, Raymond P; Devine, Dana V

    2015-04-01

    Pathogen inactivation (PI) technologies are currently licensed for use with platelet (PLT) and plasma components. Treatment of whole blood (WB) would be of benefit to the blood banking community by saving time and costs compared to individual component treatment. However, no paired, pool-and-split study directly assessing the impact of WB PI on the subsequently produced components has yet been reported. In a "pool-and-split" study, WB either was treated with riboflavin and ultraviolet (UV) light or was kept untreated as control. The buffy coat (BC) method produced plasma, PLT, and red blood cell (RBC) components. PLT units arising from the untreated WB study arm were treated with riboflavin and UV light on day of production and compared to PLT concentrates (PCs) produced from the treated WB units. A panel of common in vitro variables for the three types of components was used to monitor quality throughout their respective storage periods. PCs derived from the WB PI treatment were of significantly better quality than treated PLT components for most variables. RBCs produced from the WB treatment deteriorated earlier during storage than untreated units. Plasma components showed a 3% to 44% loss in activity for several clotting factors. Treatment of WB with riboflavin and UV before production of components by the BC method shows a negative impact on all three blood components. PLT units produced from PI-treated WB exhibited less damage compared to PLT component treatment. © 2014 AABB.

  10. Microstructural studies and wear assessments of Ti/TiC surface composite coatings on commercial pure Ti produced by titanium cored wires and TIG process

    Energy Technology Data Exchange (ETDEWEB)

    Monfared, A., E-mail: amirmonfared25@yahoo.com [Department of Materials Science and Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Kokabi, A.H.; Asgari, S. [Department of Materials Science and Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of)

    2013-01-15

    Tungsten Inert Gas (TIG) process and titanium cored wires filled with micro size TiC particles were employed to produce surface composite coatings on commercial pure Ti substrate for wear resistance improvement. Wire drawing process was utilized to produce several cored wires from titanium strips and titanium carbide powders. Subsequently, these cored wires were melted and coated on commercial pure Ti using TIG process. This procedure was repeated at different current intensities and welding travel speeds. Composite coating tracks were found to be affected by TIG heat input. The microstructural studies using optical and scanning electron microscopy supported by X-ray diffraction showed that the surface composite coatings consisted of {alpha} Prime -Ti, spherical and dendritic TiC particles. Also, greater volume fractions of TiC particles in the coatings were found at lower heat input. A maximum microhardness value of about 1100 HV was measured which is more than 7 times higher than the substrate material. Pin-on-disk wear tests exhibited a better performance of the surface composite coatings than the untreated material which was attributed to the presence of TiC particles in the microstructure. -- Highlights: Black-Right-Pointing-Pointer Ti/TiC composite coatings were produced on the CP-Ti. Black-Right-Pointing-Pointer Titanium cored wire and TIG process were employed for production of the coatings. Black-Right-Pointing-Pointer Decreasing heat input, increased the volume fraction of TiC in the coatings. Black-Right-Pointing-Pointer The maximum microhardness obtained in the lowest heat input. Black-Right-Pointing-Pointer The wear resistance of the coatings improved due to the formation of TiC particles.

  11. Synthesis optimization and characterization of chitosan-coated iron oxide nanoparticles produced for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Unsoy, Gozde, E-mail: gozdeunsoy@hotmail.com [Middle East Technical University, Department of Biotechnology (Turkey); Yalcin, Serap [Middle East Technical University, Department of Biological Sciences (Turkey); Khodadust, Rouhollah [Middle East Technical University, Department of Biotechnology (Turkey); Gunduz, Gungor [Middle East Technical University, Department of Chemical Engineering (Turkey); Gunduz, Ufuk, E-mail: ufukg@metu.edu.tr [Middle East Technical University, Department of Biological Sciences (Turkey)

    2012-11-15

    The chitosan-coated magnetic nanoparticles (CS MNPs) were in situ synthesized by cross-linking method. In this method; during the adsorption of cationic chitosan molecules onto the surface of anionic magnetic nanoparticles (MNPs) with electrostatic interactions, tripolyphosphate (TPP) is added for ionic cross-linking of the chitosan molecules with each other. The characterization of synthesized nanoparticles was performed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS/ESCA), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), thermal gravimetric analysis (TGA), and vibrating sample magnetometry (VSM) analyses. The XRD and XPS analyses proved that the synthesized iron oxide was magnetite (Fe{sub 3}O{sub 4}). The layer of chitosan on the magnetite surface was confirmed by FTIR. TEM results demonstrated a spherical morphology. In the synthesis, at higher NH{sub 4}OH concentrations, smaller sized nanoparticles were obtained. The average diameters were generally between 2 and 8 nm for CS MNPs in TEM and between 58 and 103 nm in DLS. The average diameters of bare MNPs were found as around 18 nm both in TEM and DLS. TGA results indicated that the chitosan content of CS MNPs were between 15 and 23 % by weight. Bare and CS MNPs were superparamagnetic. These nanoparticles were found non-cytotoxic on cancer cell lines (SiHa, HeLa). The synthesized MNPs have many potential applications in biomedicine including targeted drug delivery, magnetic resonance imaging (MRI), and magnetic hyperthermia.

  12. Recuperação de metais de catalisadores usados de hidrotratamento (NiMo E CoMo/AL2O3 Recovery of metals from spent hydrotreating catalysts (NiMo and CoMo/ Al2O3

    Directory of Open Access Journals (Sweden)

    Júlio C. Afonso

    1997-08-01

    Full Text Available This work presents a detailed study of the leaching behavior of deactivated hydrotreating catalysts (CoMo, NiMo/Al2O3 in presence of oxalate and NH4+ ions in various media. The yield of metals recovery may be optimized by adjusting several experimental parameters (time, temperature, etc. Leaching is limited by physical factors (diffusional effects caused by coke and by the existence of silicate/spinel-like species which are poorly soluble in leaching solutions. Coke may be eliminated by an oxidation step at temperatures between 300-400ºC. Above 400ºC, solubilization of Ni and Co is drastically reduced. 50-90% wt of sulphate species and 15-30% wt of phosphate ions are solubilized during leaching. Silicon (as SiO2 is not solubilized. The best Ni-Co-Mo recoveries are in the 70-90% wt range; Fe recovery may be quantitative, whereas Al leaching may be lower than 5% wt.

  13. Physical and chemical characterization of Ag-doped Ti coatings produced by magnetron sputtering of modular targets

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, Tobias [Department for Functional Materials in Medicine and Dentistry, School of Dentistry, University of Würzburg, Pleicherwall 2, 97070 Würzburg (Germany); Institute of Tissue Engineering and Regenerative Medicine, University Hospital of the Julius-Maximilians University, Röntgenring 11, 97070 Würzburg (Germany); Warmuth, Franziska [Department for Functional Materials in Medicine and Dentistry, School of Dentistry, University of Würzburg, Pleicherwall 2, 97070 Würzburg (Germany); Werner, Ewald; Hertl, Cornelia [Institute of Materials Science and Mechanics of Materials, Technical University of Munich, Boltzmannstrasse 15, 85748 Garching (Germany); Groll, Jürgen; Gbureck, Uwe [Department for Functional Materials in Medicine and Dentistry, School of Dentistry, University of Würzburg, Pleicherwall 2, 97070 Würzburg (Germany); Moseke, Claus, E-mail: claus.moseke@fmz.uni-wuerzburg.de [Department for Functional Materials in Medicine and Dentistry, School of Dentistry, University of Würzburg, Pleicherwall 2, 97070 Würzburg (Germany)

    2014-11-01

    Silver-doped Ti films were produced using a single magnetron sputtering source equipped with a titanium target containing implemented silver modules under variation of bias voltage and substrate temperature. The Ti(Ag) films were characterized regarding their morphology, contact angle, phase composition, silver content and distribution as well as the elution of Ag{sup +} ions into cell media. SEM and AFM pictures showed that substrate heating during film deposition supported the formation of even and dense surface layers with small roughness values, an effect that could even be enforced, when a substrate bias voltage was applied instead. The deposition of both Ti and Ag was confirmed by X-ray diffraction. ICP-MS and EDX showed a clear correlation between the applied sputtering parameters and the silver content of the coatings. Surface-sensitive XPS measurements revealed that higher substrate temperatures led to an accumulation of Ag in the near-surface region, while the application of a bias voltage had the opposite effect. Additional elution measurements using ICP-MS showed that the release kinetics depended on the amount of silver located at the film surface and hence could be tailored by variation of the sputter parameters. - Highlights: • Modular targets were used to deposit Ti(Ag) films. • Ag-content is adjustable by bias voltage, sputtering power and substrate temperature. • Coating parameters significantly change film morphology and roughness. • A critical parameter for Ag release is the fraction of silver on the film surface.

  14. THE EFFECT OF DEPOSITION PARAMETERS ON THE CHEMICAL COMPOSITION AND CORROSION RESISTANCE OF TICXNY COATINGS PRODUCED ON HIGH-SPEED STEEL SUBSTRATES

    Directory of Open Access Journals (Sweden)

    Senna L.F.

    2001-01-01

    Full Text Available TiCxNy coatings deposited on high-speed steel substrates have been used to enhance the tribological properties of cutting tools (hardness, wear resistance, etc. as well as their corrosion resistance in an aggressive environment. These layers are usually produced by plasma deposition techniques (PVD or CVD, and different coating properties can be obtained with each method. In this work, TiCxNy films were deposited on AISI M2 high-speed steel substrates by the reactive magnetron sputtering technique. A series of samples with a variety of reactive gas mixtures (nitrogen and methane, substrate biases, and deposition temperatures was produced. As a result, coatings with different chemical compositions were deposited for each group of deposition parameters. Gas mixture composition and substrate bias directly affected the chemical composition of the coating, while deposition temperature influenced the chemical composition of TiCxNy layers to a very low extent.

  15. The effect of colouring agent on the physical properties of glass ceramic produced from waste glass for antimicrobial coating deposition

    Science.gov (United States)

    Juoi, J. M.; Ayoob, N. F.; Rosli, Z. M.; Rosli, N. R.; Husain, K.

    2016-07-01

    Domestic waste glass is utilized as raw material for the production of glass ceramic material (GCM) via sinter crystallisation route. The glass ceramic material in a form of tiles is to be utilized for the deposition of Ag-TiO2 antimicrobial coating. Two types of soda lime glass (SLG) that are non-coloured and green SLG are utilised as main raw materials during the batch formulation in order to study the effect of colouring agent (Fe2O3) on the physical and mechanical properties of glass ceramic produced. Glass powder were prepared by crushing bottles using hammer milled with milling machine and sieved until they passed through 75 µm sieve. The process continues by mixing glass powder with ball clay with ratio of 95:5 wt. %, 90:10 wt. % and 85:15 wt. %. Each batch mixture was then uniaxial pressed and sintered at 800°C, 825 °C and 850 °C. The physical and mechanical properties were then determined and compared between those produced from non-coloured and green coloured SLG in order to evaluate the effect of colouring agent (Fe2O3) on the GCM produced. The optimum properties of non-coloured SLG is produced with smaller ball clay content (10 wt. %) compared to green SLG (15 wt. %). The physical properties (determined thru ASTM C373) of the optimized GCM produced from non-coloured SLG and green SLG are 0.69 % of porosity, 1.92 g/cm3 of bulk density, 0.36 % of water absorption; and 1.96 % of porosity, 2.69 g/cm3 of bulk density, 0.73 % of water absorption; respectively. Results also indicate that the most suitable temperature in producing GCM from both glasses with optimized physical and mechanical properties is at 850 °C.

  16. Mössbauer study of carbon coated iron magnetic nanoparticles produced by simultaneous reduction/pyrolysis

    Science.gov (United States)

    Mendonça, Fernanda G.; Ardisson, José D.; Rosmaninho, Marcelo G.; Lago, Rochel M.; Tristão, Juliana C.

    2011-11-01

    Magnetic iron nanoparticles immersed in a carbon matrix were produced by a combined process of controlled dispersion of Fe3 + ions in sucrose, thermal decomposition with simultaneous reduction of iron cores and the formation of the porous carbonaceous matrix. The materials were prepared with iron contents of 1, 4 and 8 in %wt in sucrose and heated at 400, 600 and 800°. The samples were analyzed by XRD, Mössbauer spectroscopy, magnetization measurements, TG, SEM and TEM. The materials prepared at 400° are composed essentially of Fe3O4 particles and carbon, while treatments at higher temperatures, e.g. 600 and 800° produced as main phases Fe0 and Fe3C. The Mössbauer spectra of samples heated at 400° showed two sextets characteristic of a magnetite phase and other contributions compatible with Fe3 + and Fe2 + phases in a carbonaceous matrix. Samples treated at temperatures above 600° showed the presence of metallic iron with concentrations between 16-43%. The samples heated at 800° produced higher amounts of Fe3C (between 20% and 58%). SEM showed for the iron 8% sample treated at 600-800°C particle sizes smaller than 50 nm. Due to the presence of Fe0 particles in the carbonaceous porous matrix the materials have great potential for application as magnetic adsorbents.

  17. A human-mouse hybridoma producing monoclonal antibody against human sperm coating antigen.

    Science.gov (United States)

    Kyurkchiev, S D; Shigeta, M; Koyama, K; Isojima, S

    1986-01-01

    Since anti-sperm antibodies were first discovered in the sera of women, the relationship of these antibodies to sterility has been studied by many investigators. In order to determine the antigens of spermatozoa responsible for raising antibodies to spermatozoa in humans, many studies have been carried out by purifying human spermatozoa cell membrane and seminal plasma components. Since it was found that the purification was difficult by physiochemical procedures, the immunoaffinity chromatography bound monoclonal antibody (Mab) to spermatozoa antigens was attempted for this purpose. The establishment of hybridomas producing Mabs to human seminal plasma and human spermatozoa was reported by Shigeta et al. (1980), Isojima, Koyoma & Fujiwara (1982), Lee et al. (1982) and Isahakia & Alexander (1984). The ordinary approaches to obtain the Mabs consisted of xenogenic immunization with human semen and cell fusion of immunized spleen cells with mouse myeloma cells. However, the antigenic epitopes of human spermatozoa, which induced antibody production, are xenogenic for the mouse, and therefore there is a possibility that there is a difference in recognized antigenic epitopes in humans as isotypic and in mice as xenogenic. In order to study these antigenic epitopes, which correspond to antibodies against spermatozoa in women, the establishment of human-mouse hybridomas, which produced anti-semen antibodies as produced in sterile women, became essential. In these studies, we used recently developed cell fusion techniques to fuse immunized human peripheral lymphocytes with mouse myeloma cells. PMID:3456978

  18. Microstructure and microhardness characterization of Cr{sub 3}C{sub 2}-SiC coatings produced by the plasma transferred arc method

    Energy Technology Data Exchange (ETDEWEB)

    Islak, Serkan [Kastamonu Univ. (Turkey). Cide Rifat Ilgaz Vocational High School; Eski, Oezkan [Kastamonu Univ. (Turkey). Kastamonu Vocational High School; Buytoz, Soner [Firat Univ., Elazig (Turkey). Dept. of Metallurgy and Materials Engineering; Karagoez, Muzaffer [Bartin Univ. (Turkey). Dept. of Metallurgical and Materials Engineering; Stokes, Joseph [Dublin City Univ. (Ireland). School of Mechanical and Manufacturing Engineering

    2012-07-01

    The purpose of this work was to investigate the coatings made of Cr{sub 3}C{sub 2} and SiC powder manufactured on AISI 304 stainless steel applied by the plasma transferred arc (PTA) welding process. SiC content in the produced coated layer was varied between 0-100 wt. % and the effect of SiC concentration on the microstructure and hardness of the coating was measured experimentally. SEM analyses revealed that the composite coatings had a homogeneous, nonporous, and crack-free microstructure. Dendrites and interdendrite eutectics formed on the coating layer, subject to the temperature gradient and the solidification ratio. There was a significant increase in the hardness of coating layers with the effect of the {gamma}-(Fe,Ni), Cr{sub 7}C{sub 3}, Cr{sub 23}C{sub 6}, Fe{sub 5}C{sub 2}, Cr{sub 3}Si, CrSi{sub 2}, Fe{sub 0.64}Ni{sub 0.36}, CFe{sub 15.1}, C-(Fe,Cr)-Si phases formed in the microstructure. In comparison to the substrate, the microhardness of the coatings produced by PTA were 2.5-3.5 times harder. (orig.)

  19. On the Use of the Electrospinning Coating Technique to Produce Antimicrobial Polyhydroxyalkanoate Materials Containing In Situ-Stabilized Silver Nanoparticles

    Directory of Open Access Journals (Sweden)

    Jinneth Lorena Castro-Mayorga

    2016-12-01

    Full Text Available Electro-hydrodynamic processing, comprising electrospraying and electrospinning techniques, has emerged as a versatile technology to produce nanostructured fiber-based and particle-based materials. In this work, an antimicrobial active multilayer system comprising a commercial polyhydroxyalkanoate substrate (PHA and an electrospun PHA coating containing in situ-stabilized silver nanoparticles (AgNPs was successfully developed and characterized in terms of morphology, thermal, mechanical, and barrier properties. The obtained materials reduced the bacterial population of Salmonella enterica below the detection limits at very low silver loading of 0.002 ± 0.0005 wt %. As a result, this study provides an innovative route to generate fully renewable and biodegradable materials that could prevent microbial outbreaks in food packages and food contact surfaces.

  20. Moessbauer study of carbon coated iron magnetic nanoparticles produced by simultaneous reduction/pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Mendonca, Fernanda G. [Universidade Federal de Minas Gerais, Departamento de Quimica - ICEx (Brazil); Ardisson, Jose D. [CDTN, Laboratorio de Fisica Aplicada, Centro de Desenvolvimento de Tecnologia Nuclear (Brazil); Rosmaninho, Marcelo G.; Lago, Rochel M.; Tristao, Juliana C., E-mail: juliana@ufv.br [Universidade Federal de Minas Gerais, Departamento de Quimica - ICEx (Brazil)

    2011-11-15

    Magnetic iron nanoparticles immersed in a carbon matrix were produced by a combined process of controlled dispersion of Fe{sup 3 + } ions in sucrose, thermal decomposition with simultaneous reduction of iron cores and the formation of the porous carbonaceous matrix. The materials were prepared with iron contents of 1, 4 and 8 in %wt in sucrose and heated at 400, 600 and 800 Degree-Sign . The samples were analyzed by XRD, Moessbauer spectroscopy, magnetization measurements, TG, SEM and TEM. The materials prepared at 400 Degree-Sign are composed essentially of Fe{sub 3}O{sub 4} particles and carbon, while treatments at higher temperatures, e.g. 600 and 800 Degree-Sign produced as main phases Fe{sup 0} and Fe{sub 3}C. The Moessbauer spectra of samples heated at 400 Degree-Sign showed two sextets characteristic of a magnetite phase and other contributions compatible with Fe{sup 3 + } and Fe{sup 2 + } phases in a carbonaceous matrix. Samples treated at temperatures above 600 Degree-Sign showed the presence of metallic iron with concentrations between 16-43%. The samples heated at 800 Degree-Sign produced higher amounts of Fe{sub 3}C (between 20% and 58%). SEM showed for the iron 8% sample treated at 600-800 Degree-Sign C particle sizes smaller than 50 nm. Due to the presence of Fe{sup 0} particles in the carbonaceous porous matrix the materials have great potential for application as magnetic adsorbents.

  1. Study on Anti-ablation Property of CrNiMo Steel Irradiated by Laser%CrNiMo钢激光淬火处理的抗烧蚀性能研究

    Institute of Scientific and Technical Information of China (English)

    王文凯; 明学勤

    2009-01-01

    通过激光淬火表面强化技术,在CrNiMo钢表面形成马氏体相变的表面强化薄层.采用小电流累积烧蚀方法分解了材料烧蚀过程;对比分析相同烧蚀条件下CrNiMo钢在激光处理与未经激光处理的表面烧蚀形貌及其烧蚀质量差.结果表明:激光淬火确实能提高材料的抗烧蚀性能.%The thin strengthening layer on the CrNiMo steel surface was prepared by laser surface hardening. The ablation process of the steel was decomposed by the method of accumulated ablation with low current. The ablation surface and mass difference of the original steel and the steel irradiated by laser were analyzed. The results show that the CrNiMo steel through laser guenching indeed promotes the anti-ablation properties of the material.

  2. Sugar-coated: exopolysaccharide producing lactic acid bacteria for food and human health applications.

    Science.gov (United States)

    Ryan, P M; Ross, R P; Fitzgerald, G F; Caplice, N M; Stanton, C

    2015-03-01

    The human enteric microbiome represents a veritable organ relied upon by the host for a range of metabolic and homeostatic functions. Through the production of metabolites such as short chain fatty acids (SCFA), folate, vitamins B and K, lactic acid, bacteriocins, peroxides and exopolysaccharides, the bacteria of the gut microbiome provide nutritional components for colonocytes, liver and muscle cells, competitively exclude potential pathogenic organisms and modulate the hosts immune system. Due to the extensive variation in structure, size and composition, microbial exopolysaccharides represent a useful set of versatile natural ingredients for the food industrial sector, both in terms of their rheological properties and in many cases, their associated health benefits. The exopolysaccharide-producing bacteria that fall within the 35 Lactobacillus and five Bifidobacterium species which have achieved qualified presumption of safety (QPS) and generally recognised as safe (GRAS) status are of particular interest, as their inclusion in food products can avoid considerable scrutiny. In addition, additives commonly utilised by the food industry are becoming unattractive to the consumer, due to the demand for a more 'natural' and 'clean labelled' diet. In situ production of exopolysaccharides by food-grade cultures in many cases confers similar rheological and sensory properties in fermented dairy products, as traditional additives, such as hydrocolloids, collagen and alginate. This review will focus on microbial synthesis of exopolysaccharides, the human health benefits of dietary exopolysaccharides and the technofunctional applications of exopolysaccharide-synthesising microbes in the food industry.

  3. Bone ingrowth potential of electron beam and selective laser melting produced trabecular-like implant surfaces with and without a biomimetic coating

    NARCIS (Netherlands)

    Biemond, J.E.; Hannink, G.J.; Verdonschot, N.J.; Buma, P.

    2013-01-01

    The bone ingrowth potential of trabecular-like implant surfaces produced by either selective laser melting (SLM) or electron beam melting (EBM), with or without a biomimetic calciumphosphate coating, was examined in goats. For histological analysis and histomorphometry of bone ingrowth depth and bon

  4. Bone ingrowth potential of electron beam and selective laser melting produced trabecular-like implant surfaces with and without a biomimetic coating

    NARCIS (Netherlands)

    Biemond, J.E.; Hannink, G.J.; Verdonschot, N.J.; Buma, P.

    2013-01-01

    The bone ingrowth potential of trabecular-like implant surfaces produced by either selective laser melting (SLM) or electron beam melting (EBM), with or without a biomimetic calciumphosphate coating, was examined in goats. For histological analysis and histomorphometry of bone ingrowth depth and

  5. 新型Cr-Ni-Mo和Cr-Ni-Co堆焊合金空蚀性能%Cavitation Erosion Resistance of Novel Cr-Ni-Mo and Cr-Ni-Co Overlaying Alloys

    Institute of Scientific and Technical Information of China (English)

    徐桂芳; 秦敏明; 雷玉成; 陈希章; 李涛

    2012-01-01

    New type Cr-Ni-Mo and Cr-Ni-Co overlaying alloys were prepared by argon tungsten-arc welding (TIG) on 304 stainless steel, and tested by cavitation vibrating device. The cavitation erosion resistance of alloys was compared through the analysis of mass loss. The alloy layer was analyzed by scanning electron microscopy (SEM), X-ray diffractometer (XRD) and microhardness tester. Results indicate that the cavitation erosion resistance of Cr-Ni-Mo and Cr-Ni-Co overlaying alloys is better than that of 304 stainless steel, and the resistance of Cr-Ni-Co is better than Cr-Ni-Mo. In the process of cavitation the damage is preferred to appear in grain boundary. Phase transformation from austenite to martensite happens in the cavitation process of Cr-Ni-Co alloy, and it is helpful to absorb the energy and delay the process of cavitation erosion, and enhance the cavitation erosion resistance effectively. The cavitation erosion resistance of overlaying alloys is related to hardness and work hardening ability.%采用钨极氩弧焊(TIG)将新型Cr-Ni-Mo和Cr-Ni-Co合金堆焊于304不锈钢表面进行空蚀试验,通过失重比较不同合金的抗空蚀性能.采用扫描电镜(SEM)、X射线衍射(XRD)仪和显微硬度计对合金层进行分析.结果表明:Cr-Ni-Mo和Cr-Ni-Co合金的耐空蚀性能均优越于304不锈钢,其中Cr-Ni-Co优于Cr-Ni-Mo;空蚀破坏优先出现在堆焊层的晶界处;Cr-Ni-Co合金在空蚀过程中发生了因奥氏体向马氏体的转变,有利于能量吸收,延缓了空蚀的进行,提高其耐空蚀性能;堆焊合金的抗空蚀能力与合金本身的硬度和加工硬化能力有关.

  6. Optical properties of thin flms of MEH-PPV produced by the spin-coating technique at different rotational speeds

    Directory of Open Access Journals (Sweden)

    Paulo Sérgio Soares Guimarães

    2008-08-01

    Full Text Available We present a study on the optical properties of thin flms of poly[2-methoxy-5-(20-ethyl-hexyloxy-1,4-phenylene vinylene] (MEH-PPV produced at a concentration of 10 mg/ml xylene. The solution was deposited onto glass substrates by the spin-coating technique at different rotational speeds (300, 1000 and 4000 rpm. We study the effect of rotational speeds on the sample at 300 K, by analyzing the photoluminescence (PL spectra at different points of the polymeric flm. We also analyze the effects of the excitation power on the optical behavior of MEH-PPV at 300 K. At low temperatures the PL spectra of sample A1000 (1000 rpm show a narrow peak for the electronic transition and a series of vibronic sidebands which reveal the electron coupling with two different vibronic modes. In the temperature range of 130 K to 290 K, we analyze systematically the transition lineshapes in the optical spectra using Gaussian curves.

  7. NiMo/Al{sub 2}O{sub 3}-MgO (x) catalysts. The effect of the prolonged exposure to ambient air on the textural and catalytic properties

    Energy Technology Data Exchange (ETDEWEB)

    Solis, D.; Klimova, T.; Ramirez, J. [Departamento de Ingenieria Quimica, Facultad de Quimica, UNAM. Cd. Universitaria,, Coyoacan (Mexico); Cortez, T. [Instituto Mexicano del Petroleo, Tratamiento de Crudo Maya, Eje central Lazaro Cardenas 152, Col. San Bartolo Atepehuacan, C.P. (Mexico)

    2004-11-24

    In the search to obtain stable catalysts for selective elimination of sulfur from gasoline, maintaining octane number, NiMo catalysts supported on Al-Mg mixed oxides were prepared by the sol-gel method and evaluated after 6-month storage in contact with ambient air, the results were compared with the freshly prepared samples. Both, freshly prepared and aged samples were characterized by nitrogen physisorption measurements (S{sub BET}), infrared spectroscopy (FT-IR) and X-ray powder diffraction (XRD) and high-resolution electron microscopy (HREM), they were tested in the thiophene hydrodesulfurization reaction.The results indicate that the incorporation of small amounts of magnesia (5mol%) into the alumina support, leads to the catalyst with low hydrogenation function and appropriate stability during prolonged contact with ambient conditions.

  8. Effect of Post-Weld Heat Treatment on Mechanical and Electrochemical Properties of Gas Metal Arc-Welded 316L (X2CrNiMo 17-13-2) Stainless Steel

    Science.gov (United States)

    Muhammad, F.; Ahmad, A.; Farooq, A.; Haider, W.

    2016-10-01

    In the present research work, corrosion behavior of post-weld heat-treated (PWHT) AISI 316L (X2CrNiMo 17-13-2) specimens joined by gas metal arc welding is compared with as-welded samples by using potentiodynamic polarization technique. Welded samples were PWHT at 1323 K for 480 s and quenched. Mechanical properties, corrosion behavior and microstructures of as-welded and PWHT specimens were investigated. Microstructural studies have shown grain size refinement after PWHT. Ultimate tensile strength and yield strength were found maximum for PWHT samples. Bend test have shown that PWHT imparted ductility in welded sample. Fractographic analysis has evidenced ductile behavior for samples. Potentiodynamic polarization test was carried out in a solution composed of 1 M H2SO4 and 1 N NaCl. Corrosion rate of weld region was 127.6 mpy, but after PWHT, it was decreased to 13.12 mpy.

  9. Stabilization of the high-temperature phases in ceramic coatings on zirconium alloy produced by plasma electrolytic oxidation

    Science.gov (United States)

    Apelfeld, A. V.; Betsofen, S. Y.; Borisov, A. M.; Vladimirov, B. V.; Savushkina, S. V.; Knyazev, E. V.

    2016-09-01

    The composition and structure of ceramic coatings obtained on Zr-1%Nb alloy by plasma electrolytic oxidation (PEO) in aqueous electrolyte comprising 2 g/L KOH, 6 g/L NaAlO2 and 2 g/L Na2SiO3 with addition of yttria nanopowder, have been studied. The PEO coatings of thickness ∼⃒20 μm were studied using scanning electron microscopy, X-ray microanalysis and X-ray phase analysis. Additives in the electrolyte of yttria nanopowder allowed stabilizing the high-temperature tetragonal and cubic zirconia in the coating.

  10. High-temperature thermo-mechanical behavior of functionally graded materials produced by plasma sprayed coating: Experimental and modeling results

    Science.gov (United States)

    Choi, Kang Hyun; Kim, Hyun-Su; Park, Chang Hyun; Kim, Gon-Ho; Baik, Kyoung Ho; Lee, Sung Ho; Kim, Taehyung; Kim, Hyoung Seop

    2016-09-01

    Thermal barrier coatings are widely used in aerospace industries to protect exterior surfaces from harsh environments. In this study, functionally graded materials (FGMs) were investigated with the aim to optimize their high temperature resistance and strength characteristics. NiCrAlY bond coats were deposited on Inconel-617 superalloy substrate specimens by the low vacuum plasma spraying technique. Functionally graded Ni-yttria-stabilized zirconia (YSZ) coatings with gradually varying amounts of YSZ (20%-100%) were fabricated from composite powders by vacuum plasma spraying. Heat shield performance tests were conducted using a high- temperature plasma torch. The temperature distributions were measured using thermocouples at the interfaces of the FGM layers during the tests. A model for predicting the temperature at the bond coating-substrate interface was established. The temperature distributions simulated using the finite element method agreed well with the experimental results.

  11. Microstructure and abrasive wear properties of M(Cr,Fe7C3 carbides reinforced high-chromium carbon coating produced by gas tungsten arc welding (GTAW process

    Directory of Open Access Journals (Sweden)

    Soner BUYTOZ

    2010-01-01

    Full Text Available In the present study, high-chromium ferrochromium carbon hypereutectic alloy powder was coated on AISI 4340 steel by the gas tungsten arc welding (GTAW process. The coating layers were analyzed by optical microscopy, X-ray diffraction (XRD, field-emission scanning electron microscopy (FE-SEM, X-ray energy-dispersive spectroscopy (EDS. Depending on the gas tungsten arc welding pa-rameters, either hypoeutectic or hypereutectic microstructures were produced. Wear tests of the coatings were carried out on a pin-on-disc apparatus as function of contact load. Wear rates of the all coating layers were decreased as a function of the loading. The improvement of abrasive wear resistance of the coating layer could be attributed to the high hardness of the hypereutectic M7C3 carbides in the microstruc-ture. As a result, the microstructure of surface layers, hardness and abrasive wear behaviours showed different characteristics due to the gas tungsten arc welding parameters.

  12. High abrasion resistance coating materials from organic/inorganic hybrid materials produced by the sol-gel method

    OpenAIRE

    1990-01-01

    A series of new high abrasion resistance coating materials have been prepared utilizing organic/inorganic hybrid materials formed by cohydrolyzing a metal alkoxide sol (e.g. silicon, aluminum, titanium, or zirconium metal alkoxide sol) with one or more bis(trialkoxysilane-containing) organic components or related functionalized species. These hybrid materials show optical clarity and improve the abrasion resistance of polymer substrates when applied as coatings and cured on such substrates.

  13. Structure of the local environment of titanium atoms in multicomponent nitride coatings produced by plasma-ion techniques

    Science.gov (United States)

    Krysina, O. V.; Timchenko, N. A.; Koval, N. N.; Zubavichus, Ya V.

    2016-01-01

    An experiment was performed to examine the X-ray Absorption Near-Edge Structure (XANES) and the Extended X-ray Absorption Fine Structure (EXAFS) near the K-edge of titanium in nanocrystalline titanium nitride coatings containing additives of copper, silicon, and aluminum. Using the observation data, the structure parameters of the local environment of titanium atoms have been estimated for the coatings. According to crystallographic data, the Ti-N distance in the bulk phase of titanium nitride is 2.12 Å and the Ti-Ti distance is 3.0 Å. Nearly these values have been obtained for the respective parameters of the coatings. The presence of copper as an additive in a TiN coating increases the Ti-N distance inappreciably compared to that estimated for titanium nitride, whereas addition of silicon decreases the bond distance. It has been revealed that the copper and silicon atoms in Ti-Cu-N and Ti-Si-N coatings do not enter into the crystallographic phase of titanium nitride and do not form bonds with titanium and nitrogen, whereas the aluminum atoms in Ti-Al-N coatings form intermetallic phases with titanium and nitride phases.

  14. The high temperature corrosion behaviour of Hf modified chromo-aluminised coatings produced by a single step process

    Energy Technology Data Exchange (ETDEWEB)

    Du, H.L. [Northumbria Univ., Newcastle-upon-Tyne (United Kingdom). Surface Eng. Res. Group; Kipkemoi, J. [Dept. of Mechanical Engineering, Aristoteles Univ., Thessaloniki (Greece); Tsipas, D.N. [Dept. of Mechanical Engineering, Aristoteles Univ., Thessaloniki (Greece); Datta, P.K. [Northumbria Univ., Newcastle-upon-Tyne (United Kingdom). Surface Eng. Res. Group

    1996-12-01

    In this paper the introduction of Cr, Al and Hf into the surface of the RENE 80, INC718 and 2.25Cr-1Mo steel by pack cementation in a single step process has been described. The coated alloys were subject to cyclic hot corrosion and cyclic oxidation test at 870 and 875 C. The surface treated alloys were also sulphidised at 750 C in an environment of H{sub 2}/H{sub 2}S/H{sub 2}O yielding P{sub S{sub 2}} = 10{sup -6} atm. and P{sub O{sub 2}} = 10{sup -23} atm. The coated and exposed specimens were characterised by optical microscope, SEM, EPMA, EDX and XRD. Cyclic hot corrosion and cyclic oxidation tests showed that the presence of the Cr-Al-Hf on the surface of the alloys enhanced their corrosion resistance. The rare earth element modified chromium aluminide coatings showed superior protectivity. However the Cr-Al-Hf coating on INC718 delayed the formation of the refractory metal sulphides in sulphidising atmosphere and thereby reduced its sulphidation resistance whilst the coating on 2.25Cr-1Mo steel only slightly increased its resistance to sulphidation attack. (orig.)

  15. Gold nanoparticles: BSA (Bovine Serum Albumin) coating and X-ray irradiation produce variable-spectrum photoluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kuo-Hao [Department of Electrophysics, National Chiao Tung University, Hsinchu, Taiwan (China); Institute of Physics, Academia Sinica, Taipei 115, Taiwan (China); Lai, Sheng-Feng [Institute of Physics, Academia Sinica, Taipei 115, Taiwan (China); Department of Engineering Science, National Cheng Kung University, Tainan 701, Taiwan (China); Lin, Yan-Cheng; Chou, Wu-Ching [Department of Electrophysics, National Chiao Tung University, Hsinchu, Taiwan (China); Ong, Edwin B.L. [Institute of Physics, Academia Sinica, Taipei 115, Taiwan (China); Tan, Hui-Ru [Institute of Materials Research and Engineering, 3 Research Link, 117602 (Singapore); Tok, Eng Soon [Physics Department, National University of Singapore, 117542 (Singapore); Yang, C.S. [Center for Nanomedicine, National Health Research Institutes, Miaoli 350, Taiwan (China); Margaritondo, G. [Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne (Switzerland); Hwu, Y., E-mail: phhwu@sinica.edu.tw [Institute of Physics, Academia Sinica, Taipei 115, Taiwan (China); Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan (China); Institute of Optoelectronic Sciences, National Taiwan Ocean University, Keelung 202, Taiwan (China)

    2015-01-15

    We show that by using different x-ray irradiation times of BSA-coated Au nanoparticles (NPs) we can change their ultraviolet-stimulated photoluminescence and shift the spectral weight over the visible spectral range. This is due to the interplay of two emission bands, one due to BSA and the other related to gold. The emission properties did not change with time over a period of several months. - Highlights: • Gold nanoparticles (Au NPs) coated with Bovine Serum Albumin (BSA) are synthesized by x-ray irradiation. • BSA coated AuNPs with ∼1 nm size show strong photoluminescence in red by UV excitation. • The blue photoluminescence of BSA increase with x-ray irradiation. • Increase x-ray irradiation time during the synthesis shift the color of the colloid from red to blue.

  16. Transparent binary-thickness coatings on metal substrates that produce binary patterns of orthogonal elliptical polarization states in reflected light

    Science.gov (United States)

    Azzam, Rasheed M. A.; Angel, Wade W.

    1992-12-01

    A reflective division-of-wavefront polarizing beam splitter is described that uses a dual- thickness transparent thin-film coating on a metal substrate. A previous design that used a partially clad substrate at the principal angle of the metal [Azzam, JOSA A 5, 1576 (1988)] is replaced by a more general one in which the substrate is coated throughout and the film thickness alternates between two non-zero levels. The incident linear polarization azimuth is chosen near, but not restricted to, 45 degree(s) (measured from the plane of incidence), and the angle of incidence may be selected over a range of values. The design procedure, which uses the two-dimensional Newton-Raphson method, is applied to the SiO2-Au film- substrate system at 633 nm wavelength, as an example, and the characteristics of the various possible coatings are presented.

  17. Enhanced Droplet Erosion Resistance of Laser Treated Nano Structured TWAS and Plasma Ion Nitro-Carburized Coatings for High Rating Steam Turbine Components

    Science.gov (United States)

    Pant, B. K.; Arya, Vivek; Mann, B. S.

    2010-09-01

    This article deals with surface modification of twin wire arc sprayed (TWAS) and plasma ion nitro-carburized X10CrNiMoV1222 steel using high power diode laser (HPDL) to overcome water droplet erosion occurring in low pressure steam turbine (LPST) bypass valves and LPST moving blades used in high rating conventional, critical, and super critical thermal power plants. The materials commonly used for high rating steam turbines blading are X10CrNiMoV1222 steel and Ti6Al4V titanium alloy. The HPDL surface treatment on TWAS coated X10CrNiMoV1222 steel as well as on plasma ion nitro-carburized steel has improved water droplet resistance manifolds. This may be due to combination of increased hardness and toughness as well as the formation of fine grained structure due to rapid heating and cooling rates associated with the laser surface treatment. The water droplet erosion test results along with their damage mechanism are reported in this article.

  18. Corrosion resistance of Al-based coatings in flowing Pb–15.7Li produced by aluminum electrodeposition from ionic liquids

    Directory of Open Access Journals (Sweden)

    Sven-Erik Wulf

    2016-12-01

    Full Text Available Reduced activation ferritic–martensitic steels are intended to serve as structural materials in different blanket designs, e.g. HCLL, DCLL and WCLL. In these designs the material is supposed to be in direct contact with the flowing liquid breeder material Pb–15.7Li at an operating temperature of up to 550°C. These conditions will lead to severe corrosion attack of the steel and high corrosion rates of up to 400µm per year are reported in the literature. To avoid or reduce corrosion Al-based corrosion barriers were developed in the last years by using electrochemical techniques to deposit aluminum. Until now two processes have been developed. The first one, so called ECA process, is based on volatile toluene electrolytes. Long-term corrosion experiments on these coatings indicated reduced corrosion rates compared to bare Eurofer steel in flowing Pb–15.7Li. However, these Fe–Al scales showed inhomogeneous corrosion attack of the corrosion barrier itself. In this study the improved ECX process was applied to produce Al-based coatings. The short-term corrosion behavior of such barrier coatings was analyzed for up to 4000h by diameter measurements and metallographic examinations. The investigation revealed uniform corrosion in comparison to inhomogeneous attack in case of ECA coated samples and reduced corrosion rates of around 20µm/a even for low exposure times of 4000h.

  19. Coating Nanoparticles with Plant-Produced Transferrin-Hydrophobin Fusion Protein Enhances Their Uptake in Cancer Cells

    DEFF Research Database (Denmark)

    Reuter, Lauri J.; Shahbazi, Mohammad-Ali; Makila, Ermei M.

    2017-01-01

    to a surfactant phase in an aqueous two-phase system, and the transferrin moiety was able to reversibly bind iron. Coating porous silicon nanoparticles with the fusion protein resulted in uptake of the nanoparticles in human cancer cells. This study provides a proof-of concept for the functionalization...

  20. The analysis of impact of irregularity in radionuclide coating of scaffold on the distribution of absorbed dose produced by grid of microsources

    Directory of Open Access Journals (Sweden)

    N. A. Nerosin

    2015-01-01

    Full Text Available The impact of irregularity in radionuclide coating of scaffold on the distribution of absorbed dose produced by grid of microsources was analyzed. On engineering software MATHCAD the program for calculation of absorbed dose produced by grid of microsources was created. To verify this algorithm the calculation model for MCNP code was established and represented the area consisted of soft biological tissue or any other tissue in which the grid of microsources was incorporated. Using the developed system the value of possible systematic irregular coating of radioactivity on the microsource’s core was analyzed. The distribution of activity along the surface of microsource was simulated to create distribution of absorbed dose rate corresponding to experimental data on radiation injury. The obtained model of microsource with irregular distribution of activity was compared to conventional microsource with core coated regularly along the entire area of the silver stem by main dosimetry characteristics. The results showed that even for extremely irregular distribution of activity the distribution of dose rate produced by microsource in the tumor area was not substantially different from dose-rate field obtained for microsource with regularly coated activity. The differences in dose rates (up to 10% in areas which were the nearest to the center of the grid were significantly lower than its decline from center to periphery of the grid. For spatial distribution of absorbed dose for specific configuration of microsource set and tracing of curves of equal level by selected cut-off the program SEEDPLAN was developed. The developed program represents precisely enough the spatial distribution of selected configuration set of microsources using results of calculation data for absorbed dose around the single microsource as basic data and may be used for optimal planning of brachytherapy with microsources. 

  1. Composite Nickel Coatings Produced on 6XXX Series Aluminium Alloys with the Addition of Vanadium / Kompozytowe Powłoki Niklowe Wytwarzane Na Stopach Aluminum Serii 6XXX Z Dodatkiem Wanadu

    Directory of Open Access Journals (Sweden)

    Nowak M.

    2015-12-01

    Full Text Available Studies of composite nickel coatings electrolytically deposited on aluminium alloys with different content of vanadium were described. Composite coatings were deposited from a Watts bath containing fine-dispersed SiC powder particles in an amount of 20 g/l and organic matters such as saccharin and sodium laurate. The morphology, structure and thickness of the obtained composite coatings were presented. The corrosion resistance of produced coatings was examined by electrochemical method. Basing on the results of studies it was found that coatings obtained with the sole addition of saccharin were characterized by numerous surface defects. The addition of sodium laurate eliminated the occurrence of defects caused by hydrogen evolution and the resulting coatings were continuous with good adhesion to the substrate. The distribution of the ceramic SiC phase in coatings was fairly uniform for all the examined variants of aluminium alloys. SEM examinations did not reveal the phenomenon of the ceramic particles agglomeration.

  2. A new titanium based alloy Ti-27Nb-13Zr produced by powder metallurgy with biomimetic coating for use as a biomaterial.

    Science.gov (United States)

    Mendes, Marcio W D; Ágreda, Carola G; Bressiani, Ana H A; Bressiani, José C

    2016-06-01

    Titanium alloys are widely used in biomedical applications due to their excellent properties such as high strength, good corrosion resistance and biocompatibility. Titanium alloys with alloying elements such as Nb and Zr are biocompatible and have Young's modulus close to that of human bone. To increase the bioactivity of titanium alloy surfaces is used chemical treatment with NaOH followed by immersion in simulated body fluid (SBF). The purpose of this study was to produce the alloy Ti-27Nb-13Zr with low Young's modulus by powder metallurgy using powders produced by the HDH process. The formation of biomimetic coatings on samples immersed in SBF for 3, 7, 11 and 15 days was evaluated. Characterization of the coating was performed by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and scanning electron microscope. The microstructure and composition of the alloy were determined using SEM and XRD, while the mechanical properties were evaluated by determining the elastic modulus and the Vickers microhardness. The sintered alloys were composed of α and β phases, equiaxed grains and with density around 97.8% of its theoretical density. The Vickers microhardness and elasticity modulus of the alloy were determined and their values indicate that this alloy can be used as a biomaterial. Analysis of the coating revealed the presence of calcium phosphate layers on samples immersed for >3 days in the SBF solution.

  3. Influence of Nitrided Layer on The Properties of Carbon Coatings Produced on X105CrMo17 Steel Under DC Glow-Discharge Conditions

    Directory of Open Access Journals (Sweden)

    Tomasz BOROWSKI

    2016-09-01

    Full Text Available In most cases, machine components, which come in contact with each other, are made of steel. Common steel types include 100Cr6 and X105CrMo17 are widely used in rolling bearings, which are subjected to high static loads. However, more and more sophisticated structural applications require increasingly better performance from steel. The most popular methods for improving the properties of steel is carburisation or nitriding. Unfortunately, when very high surface properties of steel are required, this treatment may be insufficient. Improvement of tribological properties can be achieved by increasing the hardness of the surface, reducing roughness or reducing the coefficient of friction. The formation of composite layers on steel, consisting of a hard nitride diffusion layer and an external carbon coating with a low coefficient of friction, seems to be a prospect with significant potential. The article describes composite layers produced on X105CrMo17 steel and defines their morphology, surface roughness and their functional properties such as: resistance to friction-induced wear, coefficient of friction and corrosion resistance. The layers have been formed at a temperature of 370°C in successive processes of: nitriding in low-temperature plasma followed by deposition of a carbon coating under DC glow-discharge conditions. An evaluation was also made of the impact of the nitrided layers on the properties and morphology of the carbon coatings formed by comparing them to coatings formed on non-nitrided X105CrMo17 steel substrates. A study of the surface topography, adhesion, resistance to friction-induced wear and corrosion shows the significant importance of the substrate type the carbon coatings are formed on.DOI: http://dx.doi.org/10.5755/j01.ms.22.3.7532

  4. Bioactive ZnO Coatings Deposited by MAPLE—An Appropriate Strategy to Produce Efficient Anti-Biofilm Surfaces

    Directory of Open Access Journals (Sweden)

    Alexandra Elena Oprea

    2016-02-01

    Full Text Available Deposition of bioactive coatings composed of zinc oxide, cyclodextrin and cefepime (ZnO/CD/Cfp was performed by the Matrix Assisted Pulsed Laser Evaporation (MAPLE technique. The obtained nanostructures were characterized by X-ray diffraction, IR microscopy and scanning electron microscopy. The efficient release of cefepime was correlated with an increased anti-biofilm activity of ZnO/CD/Cfp composites. In vitro and in vivo tests have revealed a good biocompatibility of ZnO/CD/Cfp coatings, which recommend them as competitive candidates for the development of antimicrobial surfaces with biomedical applications. The release of the fourth generation cephalosporin Cfp in a biologically active form from the ZnO matrix could help preventing the bacterial adhesion and the subsequent colonization and biofilm development on various surfaces, and thus decreasing the risk of biofilm-related infections.

  5. Structure and properties of chromium-containing coatings produced by electron-beam facing in the atmosphere

    Science.gov (United States)

    Poletika, I. M.; Golkovskii, M. G.; Krylova, T. A.; Perovskaya, M. V.

    2009-03-01

    The chemical and phase compositions and the structure of layers formed by electron-beam facing of low-carbon steel with mixtures of powdered chromium and chromium carbide in air are studied. The microhardness of the layers is determined over their thickness. The faced steels are tested for bending strength, corrosion resistance, and resistance to abrasive wear. A possible mechanism of formation of the properties of the coating, i.e., the hardness, the wear resistance, and the crack resistance, is considered.

  6. A Novel One-dimensional Reduced Molybdenum(Ⅴ) Decorated with Nickel Coordination Cations: Ni[Mo6O12(OH)3(PO4)(HPO4)3]2[Ni(H2O)2][Ni(H2O)(bipy)2]4·5H2O

    Institute of Scientific and Technical Information of China (English)

    GUO Hong-Xu; WANG Qing-Hua; CHEN Chen; LIANG Min; CHEN Ling

    2008-01-01

    A novel molybdenum(Ⅴ) phosphate decorated with nickel complex cations, Ni[Mo6O12(OH)3(PO4)(HPO4)3]2-[Ni(H2O)2][Ni(H2O)(bipy)2]4·5H2O (bipy=2,2'-bipyridyl), has been hydrothermally synthesized and characterized by IR, TGA and single-crystal X-ray diffraction. Two {Mo6P4} clusters are linked via one Ni cation to form a Ni[Mo6P4]2 dimer unit, which is further connected together by additional nickel coordination complex ions to give 1-D molybdenum(Ⅴ) phosphate chain-like structure. A probe reaction of the oxidation of benzaldehyde with H2O2 using the title compound as catalyst was carried out in a liquid-solid system, showing that the compound had high oxidative catalytic activity to the reaction.

  7. Influence of Ni/Mo ratio on structural and electrical properties of double perovskite system Sr{sub 2}Ni{sub 1+x}Mo{sub 1-x}O{sub 6-δ}

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Pravin; Singh, Nitish Kumar; Singh, Rajesh Kumar; Singh, Prabhakar [Indian Institute of Technology (BHU), Department of Physics, Varanasi (India)

    2015-11-15

    Technologically important double perovskite system Sr{sub 2}Ni{sub 1+x}Mo{sub 1-x}O{sub 6-δ} with x = 0.00, 0.05, 0.10, and 0.15 was prepared by solution combustion method. The structural and the Rietveld analysis of compositions revealed the formation of double perovskite tetragonal phase Sr{sub 2}NiMoO{sub 6} with space group I4/m as a major phase. SrMoO{sub 4} and NiO were also observed as minor phases. Microstructural studies depicted the formation of uniform grains for all the samples. The average grain size was found to lie between the ranges of 1-4 μm. XPS analysis of the synthesized compositions showed the decreasing ratio of Mo{sup 5+} to Mo{sup 6+} ions in the system with increasing Ni content, which played an important role in the conduction mechanism. The thermal expansion coefficient (TEC) of all compositions indicated that it is more compatible to the TEC of standard electrolytes. The electrical conductivity for all the compositions was studied using impedance spectroscopy in the temperature range 200-600 C. Composition with x = 0.05 showed better electrical conductivity with good catalytic activity. (orig.)

  8. Study on Oxidation Behavior of NiMoCr Metallic Interconnector for SOFC%固体氧化物燃料电池(SOFC)用NiMOCr金属连接体氧化行为研究

    Institute of Scientific and Technical Information of China (English)

    卢凤双; 田宇鹏

    2011-01-01

    金属作为固体氧化物燃料电池(SOFC)连接体材料已成为可能并成为研究热点.本论文对SOFC用NiMoCr合金分别在SOFC阴极和阳极气氛条件下的高温氧化性能作了详细的研究.结果表明:阳极(燃料极)条件下氧化所形成的是MnCr2O4尖晶石;阴极(空气极)条件下氧化所形成的是不含Cr的致密NiMnO4型尖晶石,能有效抑制Cr的挥发,降低阴极Cr毒化现象,并提高合金表面氧化物的导电性能.%At present, the metallic interconnector used for solid oxidation fuel cell (SOFC) is actively researched. In this paper, high temperature oxidation behaviors in the cathode and anode environment of SOFC were separately studied. The results show that the MnCr2O4 appears in the anode environment and NiMn2O4 appears in the cathode environment which can reduce poisoning of the cathode because of restraining the volatilization of Cr and increasing the conduction of electricity of oxidation layer.

  9. 高水热稳定性加氢脱氧Ni-Mo复合氧化物催化剂的制备%Preparation of Ni-Mo Composite Oxide Catalysts with High Hydrothermal Stability for Hydrodeoxygenation

    Institute of Scientific and Technical Information of China (English)

    任阳阳; 宋运晶; 段艳; 侯凯湖

    2015-01-01

    以动植物油脂为原料加氢脱氧生产生物柴油的关键是开发具有优异加氢脱氧活性和稳定性的新型催化剂.今采用溶胶凝胶法制备了本体型Ni-Mo复合氧化物加氢脱氧催化剂,并对其进行了XRD、BET等表征,以含 20%小桐子油的正辛烷溶液为原料,在连续固定床反应装置上考察了催化剂的活性和水热稳定性.结果表明:溶胶凝胶法可制备出具有优异活性的钼镍复合氧化物催化剂,水热处理后催化剂的比表面积和孔容减小以及形成了部分NiMoO 4新相,前者使催化剂的活性下降,后者使催化剂的活性增加,二者的综合作用使水热处理催化剂的活性下降.提高催化剂的焙烧温度或添加镁铝尖晶石等方法可有效改善催化剂的水热稳定性和调控小桐子油的加氢脱氧反应路径.在330℃、2~5 h?1和310℃、2 h?1条件下,小桐子油在700℃焙烧、水热处理前后的催化剂上的脱氧率均高达99.0%以上.与在水热处理前催化剂上的反应结果相比,小桐子油在水热处理后催化剂上的脱羧基、脱羰基反应产物增加了15%.%Key issue of biodiesel production technique via the hydrodeoxygenation of animal and vegetable fats is to develop novel catalysts with excellent hydrodeoxygenation(HDO) activity and stability. A kind of unsupported Ni-Mo composite oxide catalysts were prepared by the sol-gel method in this paper, The prepared catalysts were characterized by XRD and BET. Using the solution of 20%(vol) jatropha curcas oil + 80%(vol) n-octane as the feed, the HDO performance and hydrothermal stability of the catalysts were investigated in a continuous flow fixed-bed reactor. The results show that Mo-Ni composite oxide catalysts prepared by sol-gel method could possess higher hydrodeoxygenation activity.The surface area and pore volume of the catalysts decreases and the some NiMoO 4 can be formed after the hydrothermal treatment. The surface area and pore volume

  10. The Structure And Properties Of Mixed Welded Joints Made Of X10NiCrAlTi32-21 And X6CrNiMoTi17-12-2 Steels

    Directory of Open Access Journals (Sweden)

    Sieczkowski K.

    2015-09-01

    Full Text Available This paper describes the welding technology applied for mixed joints of tubes made of austenitic steels in the X10NiCrAlTi32-21 and X6CrNiMoTi17-12-2 grades. One made a butt joint and a multi-run joint, with the inert gas welding method and a non-consumable electrode. The mechanical properties were tested in the following scope: static tensile test, bending test from the side of the face and from the side of the root, impact test of the joint and hardness measurements. The tests were supplemented by the assessment of the macrostructure and microstructure of the joint. The performed non-destructive and structural tests did not reveal any welding imperfections, and the mechanical test results confirmed high properties of the welded joint. On this basis, the joint was classified into the “B” quality level according to PN EN ISO 5817. The mechanical and structural test results constitute the basis for qualification of the welding technology according to PN EN ISO 15614.

  11. Combustion chemical vapor desposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States)

    1995-10-01

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings.

  12. In Vivo Differentiation of Mesenchymal Stem Cells into Insulin Producing Cells on Electrospun Poly-L-Lactide Acid Scaffolds Coated with Matricaria chamomilla L. Oil

    Directory of Open Access Journals (Sweden)

    Afsaneh Fazili

    2016-09-01

    Full Text Available Objective: This study examined the in vivo differentiation of mesenchymal stem cells (MSCs into insulin producing cells (IPCs on electrospun poly-L-lactide acid (PLLA scaffolds coated with Matricaria chammomila L. (chamomile oil. Materials and Methods: In this interventional, experimental study adipose MSCs (AMSCs were isolated from 12 adult male New Zealand white rabbits and characterized by flow cytometry. AMSCs were subsequently differentiated into osteogenic and adipogenic lines. Cells were seeded onto either a PLLA scaffold (control or PLLA scaffold coated with chamomile oil (experimental. A total of 24 scaffolds were inserted into the pancreatic area of each rabbit and placement was confirmed by ultrasound. After 21 days, immunohistochemistry analysis of insulin-producing like cells on protein levels confirmed insulin expression of insulin producing cells (IPSCs. Real-time polymerase chain reaction (PCR determined the expressions of genes related to pancreatic endocrine development and function. Results: Fourier transform infrared spectroscopy (FTIR results confirmed the existence of oil on the surface of the PLLA scaffold. The results showed a new peak at 2854 cm-1 for the aliphatic CH2 bond. Pdx1 expression was 0.051 ± 0.007 in the experimental group and 0.009 ± 0.002 in the control group. There was significantly increased insulin expression in the scaffold coated with chamomile oil (0.09 ± 0.001 compared to control group (0.063 ± 0.009, P≤0.05. Both groups expressed Ngn3 and Pdx1 specific markers and pancreatic tissue was observed at 21 days post transplantation. Conclusion: The pancreatic region is an optimal site for differentiation of AMSCs to IPCs. Chamomile oil (as an antioxidant agent can affect cell adhesion to the scaffold and increase cell differentiation. In addition, the oil may lead to increased blood glucose uptake in pathways in the muscles, liver and fatty tissue of a diabetic animal model by some probable molecular

  13. The Role of SiO2 Gas in the Operation of Anti-Corrosion Coating Produced by PVD

    Directory of Open Access Journals (Sweden)

    Meysam Zarchi

    2015-09-01

    Full Text Available This study examined theSiO2 gas present in the coatings used in corrosion industry.These layers have been created by physical vapor deposition (PVD, with an appropriate performance. Sublimation of SiO2is used to protect PVD aluminum flakes from water corrosionand to generate highly porous SiO2 flakes with holes in the nanometer range. SiOx/Al/SiOx sandwiches were made as well as Ag loaded porous SiO2 as antimicrobial filler.

  14. A review of producing hard coatings by means of duplex treatments using an electroplated coating–thermochemical treatment combination

    Directory of Open Access Journals (Sweden)

    Héctor Cifuentes Aya

    2011-12-01

    Full Text Available Duplex treatments have been developed to overcome the disadvantages presented by simple treatments to surfaces of different materials and have, in a combined and complementary way, the properties that each of these methods supplies individually. The difference between thermal expansion coefficients for Fe and Cr in hard chrome plating leads to crack formation in the deposited coat, through which corrosive agents migrate and reduce the system’s integrity.Direct deposition by physical vapour deposition (PVD, used for obtaining chromium nitride films on steel substrates, is limited by high production costs, the low thickness obtained and low resistance to corrosion due to the presence of micro pores. Some studies have combined an electroplated chromium with thermochemical treatments made in a controlled atmosphere or vacuum furnaces or by plasma. This kind of duplex treatment allows compounds such as CrxN, CrxCyN and CrxCy to be obtained from chemical and micro structural transformation of chromium with nitrogen and/or carbon, the sealing of cracks in the coating and increasing the magnitude of properties like hardness and density, improving wear and abrasion and corrosion resistance.

  15. Electrochemical characterization of V{sub x}Nb{sub y}C{sub z}/Bi{sub x}Ti{sub y}O{sub z} coatings produced through thermo-reactive diffusion and the sputtering technique

    Energy Technology Data Exchange (ETDEWEB)

    Castro H, S. A.; Alfonso, J. E.; Olaya, J. J., E-mail: jealfonso@unal.edu.co [Universidad Nacional de Colombia, Departamento de Fisica, Grupo de Ciencia de Materiales y Superficies, AA-14490 Bogota (Colombia)

    2016-11-01

    We present and experimental study of the structural evolution of a bilayer V{sub x}Nb{sub y}C{sub z}/Bi{sub x}Ti{sub y}O{sub z} coating produced via thermo-reactive diffusion (TRD) and the RF sputtering process on D-2 steel substrate. The TRD treatments were carried out in a molten mixture consisting of borax, ferro-niobium, ferro-vanadium, and aluminum, at 1313 K for 3 hours, using a resistance-heating furnace. Bi{sub x}Ti{sub y}O{sub z} coatings were deposited using RF magnetron sputtering on TRD coatings, in order to carry out a study of the corrosion behavior of this compound. The crystallographic structure of the coatings was determined via X-ray diffraction, the corrosion resistance was analyzed through the potentiodynamic polarization test (Tafel Extrapolation) and electrochemical impedance spectroscopic analysis (EIS). X-ray diffraction patterns showed that the ternary coating (VNbC{sub 2}) was preferentially oriented along the [200] direction with a cubic-centered face structure, and the Bi{sub x}Ti{sub y}O{sub z} coatings were amorphous. The electrochemical studies showed that the resistance corrosion of the coatings increased with respect to the bare substrate, and that polarization resistance in the bilayer coatings increased with respect to the ternary coatings, suggesting that the titanate has anti corrosive barrier effects. (Author)

  16. Quaternary Pt{sub 2}Ru{sub 1}Fe{sub 1}M{sub 1}/C (M=Ni, Mo, or W) catalysts for methanol electro-oxidation reaction

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Min Ku; Lee, Ki Rak; Kang, Kweon Ho; Park, Geun Il [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Jeon, Hyung Joon [Kyoto University, Kyoto (Japan); McGinn, Paul J. [University of Notre Dame, Indiana (United States)

    2015-02-15

    Quaternary Pt{sub 2}Ru{sub 1}Fe{sub 1}M{sub 1}/C (M=Ni, Mo, or W) catalysts were investigated for the methanol electro-oxidation reaction (MOR). Electrocatalytic activities of the quaternary catalysts for CO electro-oxidation were studied via CO stripping experiments, and the Pt{sub 2}Ru{sub 1}Fe{sub 1}Ni{sub 1}/C and Pt{sub 2}Ru{sub 1}Fe{sub 1}W{sub 1}/C catalysts exhibited lowered on-set potential compared to that of a commercial PtRu/C catalyst. MOR activities of the quaternary catalysts were determined by linear sweep voltammetry (LSV) experiments, and the Pt{sub 2}Ru{sub 1}Fe{sub 1}W{sub 1}/C catalyst outperformed the commercial PtRu/C catalyst by 170 and 150% for the mass and specific activities, respectively. X-ray photoelectron spectroscopy (XPS) was employed to analyze surface oxidation states of constituent atoms, and it was identified that the structure of the synthesized catalysts are close to a nano-composite of Pt and constituent metal hydroxides and oxides. In addition, the XPS results suggested that the bi-functional mechanism accounts for the improved performance of the Pt{sub 2}Ru{sub 1}Fe{sub 1}Ni{sub 1}/C and Pt{sub 2}Ru{sub 1} Fe{sub 1}W{sub 1}/C catalysts.

  17. Effect of optimizing parameters of laser transformation hardening on 5CrNiMo steel Temperature Field%激光相变硬化工艺参数对5CrNiMo钢温度场的影响

    Institute of Scientific and Technical Information of China (English)

    孙文强; 李云涛; 尹博

    2012-01-01

    The process of laser phase transformation hardening,through 5CrNiMo steel,was numerically simulated by means of ANSYS software, the effect of different optimizing parameters of laser on the temperature field were analyzed, and the depth of surface hardened layer was predicted. The results showed that the distribution of temperature field experienced three stages in the process of laser transformation hardening,unsteady state, quasi-steady and unsteady state. The temperature field is proportional to the laser power,and inversely proportional to the laser beam diameter and the scan velocity. The hardness layer between the input - output area showed an uneven distribution, which presented that the hardness layer of output area was deeper than input area.%本文运用ANSYS.有限元软件对5CrNiMo合金工具钢激光相变硬化过程进行数值模拟研究,分析了不同激光工艺参数(激光功率、扫描速度、光斑直径)对激光相变硬化过程温度场的影响,并且预测硬化层深.结果表明,激光表面淬火过程温度场分布经历了非稳态到中间准稳态,然后到最后非稳态三个阶段;温度与激光功率成正比,与光斑直径和扫描速度成反比.工件扫入端与扫出端硬化层分布不均匀,呈现扫入端硬化层浅,扫出端深的特点.

  18. Soft-agar-coated filter method for early detection of viable and thermostable direct hemolysin (TDH)- or TDH-related hemolysin-producing Vibrio parahaemolyticus in seafood.

    Science.gov (United States)

    Hayashi, Sachiko; Okura, Masatoshi; Osawa, Ro

    2006-07-01

    A novel method for detecting viable and thermostable direct hemolysin (TDH)-producing or TDH-related hemolysin (TRH)-producing Vibrio parahaemolyticus in seafood was developed. The method involved (i) enrichment culture, selective for viable, motile cells penetrating a soft-agar-coated filter paper, and (ii) a multiplex PCR assay targeting both the TDH gene (tdh) and TRH gene (trh) following DNase pretreatment on the test culture to eradicate any incidental DNAs that might have been released from dead cells of tdh- or trh-positive (tdh+ trh+) strains and penetrated the agar-coated filter. A set of preliminary laboratory tests performed on 190 ml of enrichment culture that had been inoculated simultaneously with ca. 100 viable cells of a strain of tdh+ trh+ V. parahaemolyticus and dense populations of a viable strain of tdh- and trh-negative V. parahaemolyticus or Vibrio alginolyticus indicated that the method detected the presence of viable tdh+ trh+ strains. Another set of preliminary tests on 190 ml of enrichment culture that had been initially inoculated with a large number of dead cells of the tdh+ trh+ strain together with dense populations of the tdh- and trh-negative strains confirmed that the method did not yield any false-positive results. Subsequent quasi-field tests using various seafood samples (ca. 20 g), each of which was experimentally contaminated with either or both hemolysin-producing strains at an initial density of ca. 5 to 10 viable cells per gram, demonstrated that contamination could be detected within 2 working days.

  19. Coating of Microbially Produced Calcium Carbonate Precipitation on Marble%大理石表面微生物诱导碳酸钙覆膜

    Institute of Scientific and Technical Information of China (English)

    牟涛; 竹文坤; 段涛; 张友魁; 陈晓明

    2014-01-01

    选育碳酸盐矿化菌,利用其诱导CaCO3沉积,采用涂覆法和浸泡法进行细菌矿化试验,最终在大理石样品表面形成一层致密的矿化膜。采用扫描电镜(SEM)和X射线衍射(XRD)对大理石空白试样和处理后试样进行分析,并对矿化膜进行抗酸性测试。结果表明,涂覆法和浸泡法均能在大理石表面粘结一层细小颗粒,形成一层致密、厚度为50~100μm的CaCO3矿化膜。经过覆膜处理的大理石耐酸性能得到了明显提升。%CaCO3 precipitation was induced by carbonate-mineralization microbe using the immersion method and the coating method, and ifnally formed a dense mineralization membrane layer on marble sample surface. The immersed and smeared samples were characterized by scanning electron microscopic (SEM) and X-ray diffraction (XRD), as well as tested the acid-resistance of the calcium carbonate layer. Experimental results showed that both immersion method and coating method can produce calcium carbonate particle forming a layer of dense mineralization membrane of 50~100μm, acid-resistance of the coated marble samples was improved signiifcantly.

  20. Submicron MC-type reinforced coating produced by laser alloying%激光合金化引入亚微米MC型增强相的研究

    Institute of Scientific and Technical Information of China (English)

    韩甜; 王爱华; 彭锦; 吴宝业; 黄朝

    2012-01-01

    为了研究不同反应方式的原位合成或直接添加所引入的碳化物增强相对碳化物强化铁基复合涂层耐磨性能的影响,采用CO2激光器在T10钢表面激光合金化制备TiC/Fe基复合涂层,对涂层的组织结构、显微硬度和耐磨性能进行了检测和分析.结果表明,合金化层组织致密无缺陷,由γ-CrFe7C0.5相+亚微米MC相(M=Ti,Cr,W)组成,其中奥氏体在磨损过程中由于加工硬化转变成马氏体;直接添加增强相的磨损失重是原位合成反应生成增强相的2倍~3倍;Ti+C化合反应生成的碳化物含量高于TiO2+C还原反应,耐磨性能更优异.该实验结果对制备TiC强化Fe基复合涂层时陶瓷相的最佳引入方式,有一定的指导借鉴作用.%In order to study the influence of carbides produced by in situ synthesis of various chemical reactions or direct addition on wear resistance of carbide reinforced composite coatings, TiC reinforced Fe-based composite coatings were prepared on T10 steel substrate by laser alloying. Then their microstructures, phases, microhardness and wear properties were investigated and analyzed. Results showed that compact and non-defective alloy layers were obtained, consisting of γ-CrFe, C0.5 and submicron MC(M=Ti, Cr, W) particles. Austenite transformed into martensite in wear testing because of processing hardening. Wear weight loss of direct addition was 2 times to 3 times larger than that of in situ synthesis. The content of carbides produced through combination reaction between Ti and C was higher than that produced through reduction reaction between TiO2 and C, which led to a better tribological performance. The results can serve as a guide in selecting the best method of the ceramic phase introduction when preparing TiC reinforced Fe-based composite coatings.

  1. Research on the abrasive wear resistance of YDCrMoV coating produced by CO2 shielded flux-cored wire surfacing

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Caterpillar construction machines play an important part in many fields such as hydraulic and electric engineering, the construction of highway, for its particular of structure. The walking system of caterpillar construction machines is always under the condition of three-body abrasive wear. The abrasive wear of walking system is very severe, which always results in damages of components or structures of walking system of caterpillar construction machines. It is very important to repair the walking system by cladding technique. The abrasive wear properties of four kinds coatings produced by the shielded flux-cored wire surfacing for the repair of the damaged components of walking system of caterpillar construction machines have been studied experimentally on an MLS-23 type wet sand rubber wheel abrasive tester. The surfaces morphologies of the abrasively worn specimens and their microstructures are investigated by transmitting electron microscopy (TEM) after wear testing. Results show that the wear mechanism of cladding metals of the flux-cored wire No.1 and the No.2 is micro-cutting while that of the No.3 and the No.4 is micro-ploughing. The four kinds of flux-cored wire coatings present great potential applications for the repairing of caterpillar construction machines in the Three Gorges Engineering.

  2. On the influence of a TiN interlayer on DLC coatings produced by pulsed vacuum arc discharge: Compositional and morphological study

    Energy Technology Data Exchange (ETDEWEB)

    Segura-Giraldo, B. [Departamento de Fisica y Quimica, Universidad Nacional de Colombia Sede Manizales, Campus La Nubia, Km. via al aeropuerto, Manizales (Colombia); Restrepo-Parra, E., E-mail: erestrepopa@unal.edu.co [Departamento de Fisica y Quimica, Universidad Nacional de Colombia Sede Manizales, Campus La Nubia, Km. via al aeropuerto, Manizales (Colombia); Grupo de Desarrollo de Nuevos Materiales, Universidad Nacional de Colombia Sede Manizales, Campus La Nubia, Km. via al aeropuerto, Manizales (Colombia); Laboratorio de Fisica del Plasma, Universidad Nacional de Colombia Sede Manizales, Campus La Nubia, Km. via al aeropuerto, Manizales (Colombia); Arango-Arango, P.J. [Departamento de Fisica y Quimica, Universidad Nacional de Colombia Sede Manizales, Campus La Nubia, Km. via al aeropuerto, Manizales (Colombia); Laboratorio de Fisica del Plasma, Universidad Nacional de Colombia Sede Manizales, Campus La Nubia, Km. via al aeropuerto, Manizales (Colombia)

    2009-10-15

    The influence of a TiN interlayer on DLC coatings grown on silicon (1 0 0), 316 stainless steel and KCl by using the PAPVD pulsed arc discharge technique is presented in this paper. The structure of the coatings was determined by means of FTIR through observation of the absorption band modes of CH{sub 2} between 3100 and 2800 cm{sup -1} and representation of the sp{sup 3} and sp{sup 2} carbon bonds, respectively. The sp{sup 3}/sp{sup 2} bonds ratio was calculated by using the base line method and producing a value greater than 1 which was a good prediction of high hardness. XPS analysis of the films was made; the wide spectrum showed the elemental composition of the films (Ti, N, C). A narrow spectrum of C1s at binding energy of 284.48 eV was obtained, and its deconvolution showed peaks of sp{sup 3}, sp{sup 2} and Ti-C. Ti-C bonds were formed due to diffusion of carbon atoms into a TiN matrix. The concentration for the XPS spectra was calculated by using the area under the curve of sp{sup 3} and sp{sup 2} peaks. The morphology of the bilayer, including roughness, grain size and thickness was studied through SPM techniques.

  3. High-performance resin-bonded magnets produced from zinc metal-coated Sm2(Fe0.9Co0.1)17Nx fine powders

    Science.gov (United States)

    Noguchi, K.; Machida, K.; Yamamoto, K.; Nishimura, M.; Adachi, G.

    1999-09-01

    Fine powders of Sm2(Fe0.9Co0.1)17Nx (x=˜3) with particle sizes (d) around 1 μm as coated with zinc metal produced via the photodecomposition of diethylzinc [Zn(C2H5)2], which still provided high remanence (Br) and coercivity (Hcj) values of ˜1.43 T and ˜0.85 MAm-1, were molded to compression-type resin bonded Zn/Sm2(Fe0.9Co0.1)17Nx magnets with density values of ˜6.33 g cm-3. By optimizing the preparation conditions such as grinding, surface coating, and molding for them, the highest maximum energy product of (BH)max=186 kJm-3 for Hcj=0.73 MAm-1 was recorded among all kinds of the Sm-Fe-N based magnets reported to date. Furthermore, the excellent aging behavior of the bonded Zn/Sm2(Fe0.9Co0.1)17Nx magnets was observed after standing in air at ˜393 K and the thermal coefficient for permanent magnet was evaluated to be α(Br)=-0.04% K-1.

  4. Effect of adhesive properties of buffy coat on the quality of blood components produced with Top & Top and Top & Bottom bags.

    Science.gov (United States)

    Cerelli, Eugenio; Nocera, Martina; Di Bartolomeo, Erminia; Panzani, Paola; Baricchi, Roberto

    2015-04-01

    The Transfusion Medicine Unit of Reggio Emilia currently collects whole blood using conventional quadruple Fresenius Top & Top bags. In this study, new Fresenius Top & Bottom bags were assessed and compared to the routine method with regards to product quality and operational requirements. Twenty-one whole blood units were collected with both the new and the traditional bags, and then separated. Quality control data were evaluated and compared in order to estimate yield and quality of final blood components obtained with the two systems. We collected other bags, not included in the ordinary quality control programme, for comparison of platelet concentrates produced by pools of buffy coat. Compared to the traditional system, the whole blood units processed with Top & Bottom bags yielded larger plasma volumes (+5.7%) and a similar amount of concentrated red blood cells, but with a much lower contamination of lymphocytes (-61.5%) and platelets (-86.6%). Consequently, the pooled platelets contained less plasma (-26.3%) and were significantly richer in platelets (+17.9%). This study investigated the effect of centrifugation on the adhesiveness of the buffy coat to the bag used for whole blood collection. We analysed the mechanism by which this undesirable phenomenon affects the quality of packed red blood cells in two types of bags. We also documented the incomparability of measurements on platelet concentrates performed with different principles of cell counting: this vexing problem has important implications for biomedical research and for the establishment of universal product standards. Our results support the conclusion that the Top & Bottom bags produce components of higher quality than our usual system, while having equal operational efficiency. Use of the new bags could result in an important quality improvement in blood components manufacturing.

  5. Coating of 6028 Aluminum Alloy Using Aluminum Piston Alloy and Al-Si Alloy-Based Nanocomposites Produced by the Addition of Al-Ti5-B1 to the Matrix Melt

    Science.gov (United States)

    El-Labban, Hashem F.; Abdelaziz, M.; Mahmoud, Essam R. I.

    2014-10-01

    The Al-12 pctSi alloy and aluminum-based composites reinforced with TiB2 and Al3Ti intermetallics exhibit good wear resistance, strength-to-weight ratio, and strength-to-cost ratio when compared to equivalent other commercial Al alloys, which make them good candidates as coating materials. In this study, structural AA 6028 alloy is used as the base material. Four different coating materials were used. The first one is Al-Si alloy that has Si content near eutectic composition. The second, third, and fourth ones are Al-6 pctSi-based reinforced with TiB2 and Al3Ti nano-particles produced by addition of Al-Ti5-B1 master alloy with different weight percentages (1, 2, and 3 pct). The coating treatment was carried out with the aid of GTAW process. The microstructures of the base and coated materials were investigated using optical microscope and scanning electron microscope equipped with EDX analyzer. Microhardness of the base material and the coated layer were evaluated using a microhardness tester. GTAW process results in almost sound coated layer on 6028 aluminum alloy with the used four coating materials. The coating materials of Al-12 pct Si alloy resulted in very fine dendritic Al-Si eutectic structure. The interface between the coated layer and the base metal was very clean. The coated layer was almost free from porosities or other defects. The coating materials of Al-6 pct Si-based mixed with Al-Ti5-B1 master alloy with different percentages (1, 2, and 3 pct), results in coated layer consisted of matrix of fine dendrite eutectic morphology structure inside α-Al grains. Many fine in situ TiAl3 and TiB2 intermetallics were precipitated almost at the grain boundary of α-Al grains. The amounts of these precipitates are increased by increasing the addition of Al-Ti5-B1 master alloy. The surface hardness of the 6028 aluminum alloy base metal was improved with the entire four used surface coating materials. The improvement reached to about 85 pct by the first type of

  6. Investigation of the Microstructure and the Mechanical Properties of Cu-NiC Composite Produced by Accumulative Roll Bonding and Coating Processes

    Science.gov (United States)

    Shabani, Ali; Toroghinejad, Mohammad Reza

    2015-12-01

    In the present study, Cu-1.8 wt.% NiC (nickel coating) composite was produced by the combination of two methods, including accumulative roll bonding (ARB) and electroplating processes. Electroplating process was done on copper strips in order to produce a nickel-particle-reinforced composite. Microstructure, texture, and the mechanical properties of the produced composite were evaluated during various cycles of ARB using optical and scanning electron microscopes, x-ray diffraction, microhardness, and tensile tests. In addition, the results were compared with Cu-Cu and also Cu-NiS (nickel sheet) samples. It was found that nickel layers were fractured from the first cycle of the process, and nickel fragments were distributed in the copper matrix as the number of cycles was increased. Variation of orientation density of α-, β-, and τ-fibers for the produced composite was examined in different cycles. Microhardness for different elements in different cycles of Cu-NiC was also evaluated. Also, the investigation of the mechanical properties showed that by proceeding the ARB process, the tensile strength of the produced Cu-NiC and Cu-Cu samples was increased. However, improvement in the mechanical properties of composite samples was more noticeable due to the reinforcing effect of nickel particles. The elongation of composite samples showed a decrease in the primary cycles, unlike Cu-Cu ones; however, it was then increased. Finally, by using scanning electron microscopy, the fracture surfaces of Cu-NiC composite were studied to disclose the fracture mechanism of the samples.

  7. Preliminary Assessment on Contamination and Potential Ecological Risk of Thallium in Cultivated Soils around the Ni-Mo Mining Area in Songlin, Zunyi%遵义松林Ni-Mo矿区耕地土壤铊污染及潜在生态风险初步评价

    Institute of Scientific and Technical Information of China (English)

    金昭贵; 周明忠

    2013-01-01

    贵州遵义松林Ni-Mo矿区为华南下寒武统黑色页岩Ni-Mo矿化带中的典型矿区之一,对由其矿产资源开采活动引起的土壤环境质量评价具有重要的科学及实际意义.本研究以遵义松林Ni-Mo矿区耕地土壤为研究对象,采用ICP-MS分析土壤中铊的含量.分析结果显示,矿区耕地土壤中铊平均含量为1.84 mg/kg,明显高于贵州土壤表层铊元素背景值,初步认为矿区黑色页岩、Ni-Mo矿体、开采暴露于地表的尾矿及围岩碎石为矿区耕地土壤铊的来源.运用地质累积指数和潜在生态危害指数分别对耕地土壤铊污染程度和潜在生态风险进行了初步评价,结果表明:研究区耕地土壤已遭受铊污染,其污染程度评价等级可达中度-重污染;部分样品的潜在生态风险评价等级为中等,显示该区耕地土壤存在潜在生态风险,值得开展进一步的土壤铊污染修复研究.%The Ni-Mo mining area in Songlin,Zunyi,Guizhou,is a typical one within the lower Cambrian Ni-Mo mineralization zone of South China.Therefore,assessing the environmental quality of soils around the mining area is of important scientific and practical significance.The concentrations of thallium in the cultivated soils around the Ni-Mo mining area in Songlin were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) in this study.The result shows that the thallium contents (with an average of 1.84 mg/kg) in the soils are higher than the background value of thallium in the topsoil of Guizhou Province.It is preliminarily suggested that the black shales,Ni-Mo ores and Ni-Mo tailings exposed on the surface environment are major sources of thallium in the soils.In the present study,we evaluated the degree of contamination and potential ecological risk of thallium in the soils in terms of geoaccumulation index and potential ecological risk index,respectively.It is revealed that the soils around the Ni-Mo mining area in Songlin

  8. Novel method to produce {sup 109}Cd via proton irradiation of electroplated silver on a gold-coated copper backing

    Energy Technology Data Exchange (ETDEWEB)

    Gholamzadeh, Z.; Sadeghi, M.; Mirzaei, M. [Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of). Agricultural, Medical and Industrial Research School; Aref, M. [Zanjan Univ. (Iran, Islamic Republic of). Faculty of Physics

    2011-08-15

    Silver electrodeposition on gold layer was carried out by the alkaline plating baths to produce cadmium-109 via {sup nat}Ag(p, n){sup 109}Cd nuclear reaction. Gold was electrodeposited on copper backing in the beginning; the bath content consisted of 17.7 gl{sup -1} KCN, 6.6 gl{sup -1} Au, 6.6 gl{sup -1} K{sub 2}CO{sub 3} and 3.3 gl{sup -1} Na{sub 2}CO{sub 3} while acidity and temperature of the bath adjusted at 10 and 45 C respectively. A DC current density of ca 2.08 mA . cm{sup -2} was used to electroplate gold. A gold layer of 63 {mu}m thickness with suitable morphology was obtained after the electrodeposition. Silver was electrodeposited on the gold layer with 100% efficiency using a cyanide bath. The silver target was irradiated with 15 MeV proton beam and current of 150 {mu}A; the {sup 109}Cd production yield was 2.0 {mu}Ci/{mu}A . h (0.074 MBq/{mu}A . h). The target material was dissolved by 14 M HNO{sub 3}{sup .} Cadmium-109 in the dissolved target solution was separated from silver by evaporation process. Cadmium recovered with more than 88% efficiency involved non-detected silver impurity. (orig.)

  9. Corrosion resistance and biological activity of TiO2 implant coatings produced in oxygen-rich environments.

    Science.gov (United States)

    Zhang, Rui; Wan, Yi; Ai, Xing; Liu, Zhanqiang; Zhang, Dong

    2017-01-01

    The physical and chemical properties of bio-titanium alloy implant surfaces play an important role in their corrosion resistance and biological activity. New turning and turning-rolling processes are presented, employing an oxygen-rich environment in order to obtain titanium dioxide layers that can both protect implants from corrosion and also promote cell adhesion. The surface topographies, surface roughnesses and chemical compositions of the sample surfaces were obtained using scanning electron microscopy, a white light interferometer, and the Auger electron spectroscopy, respectively. The corrosion resistance of the samples in a simulated body fluid was determined using electrochemical testing. Biological activity on the samples was also analyzed, using a vitro cell culture system. The results show that compared with titanium oxide layers formed using a turning process in air, the thickness of the titanium oxide layers formed using turning and turning-rolling processes in an oxygen-rich environment increased by 4.6 and 7.3 times, respectively. Using an oxygen-rich atmosphere in the rolling process greatly improves the corrosion resistance of the resulting samples in a simulated body fluid. On samples produced using the turning-rolling process, cells spread quickly and exhibited the best adhesion characteristics.

  10. Combustion chemical vapor deposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States). School of Materials Science and Engineering

    1995-12-31

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings. In this report, the evaluation of alumina and ceria coatings on a nickel-chromium alloy is described.

  11. Combustion chemical vapor deposited coatings for thermal barrier coating systems

    Energy Technology Data Exchange (ETDEWEB)

    Hampikian, J.M.; Carter, W.B. [Georgia Institute of Technology, Atlanta, GA (United States). School of Materials Science and Engineering

    1995-12-31

    The new deposition process, combustion chemical vapor deposition, shows a great deal of promise in the area of thermal barrier coating systems. This technique produces dense, adherent coatings, and does not require a reaction chamber. Coatings can therefore be applied in the open atmosphere. The process is potentially suitable for producing high quality CVD coatings for use as interlayers between the bond coat and thermal barrier coating, and/or as overlayers, on top of thermal barrier coatings. In this report, the evaluation of alumina and ceria coatings on a nickel-chromium alloy is described.

  12. Comparative High-Temperature Corrosion Behavior of Ni-20Cr Coatings on T22 Boiler Steel Produced by HVOF, D-Gun, and Cold Spraying

    Science.gov (United States)

    Kaushal, Gagandeep; Bala, Niraj; Kaur, Narinder; Singh, Harpreet; Prakash, Satya

    2014-01-01

    To protect materials from surface degradations such as wear, corrosion, and thermal flux, a wide variety of materials can be deposited on the materials by several spraying processes. This paper examines and compares the microstructure and high-temperature corrosion of Ni-20Cr coatings deposited on T22 boiler steel by high velocity oxy-fuel (HVOF), detonation gun spray, and cold spraying techniques. The coatings' microstructural features were characterized by means of XRD and FE-SEM/EDS analyses. Based upon the results of mass gain, XRD, and FE-SEM/EDS analyses it may be concluded that the Ni-20Cr coating sprayed by all the three techniques was effective in reducing the corrosion rate of the steel. Among the three coatings, D-gun spray coating proved to be better than HVOF-spray and cold-spray coatings.

  13. Single Layer Broadband Anti-Reflective Coatings for Plastic Substrates Produced by Full Wafer and Roll-to-Roll Step-and-Flash Nano-Imprint Lithography.

    Science.gov (United States)

    Burghoorn, Marieke; Roosen-Melsen, Dorrit; de Riet, Joris; Sabik, Sami; Vroon, Zeger; Yakimets, Iryna; Buskens, Pascal

    2013-08-27

    Anti-reflective coatings (ARCs) are used to lower the reflection of light on the surface of a substrate. Here, we demonstrate that the two main drawbacks of moth eye-structured ARCs-i.e., the lack of suitable coating materials and a process for large area, high volume applications-can be largely eliminated, paving the way for cost-efficient and large-scale production of durable moth eye-structured ARCs on polymer substrates. We prepared moth eye coatings on polymethylmethacrylate (PMMA) and polycarbonate using wafer-by-wafer step-and-flash nano-imprint lithography (NIL). The reduction in reflection in the visible field achieved with these coatings was 3.5% and 4.0%, respectively. The adhesion of the coating to both substrates was good. The moth eye coating on PMMA demonstrated good performance in three prototypical accelerated ageing tests. The pencil hardness of the moth eye coatings on both substrates was polyethylene terephthalate (PET) at line speeds up to two meters per minute. The resulting coatings showed a good replication of the moth eye structures and, consequently, a lowering in reflection of the coated PET of 3.0%.

  14. Improving tribological properties of (Zn–Ni)/nano Al{sub 2}O{sub 3} composite coatings produced by ultrasonic assisted pulse plating

    Energy Technology Data Exchange (ETDEWEB)

    Ataie, Sayed Alireza, E-mail: ataie_s_alireza@metaleng.iust.ac.ir; Zakeri, Alireza

    2016-07-25

    In this study pulse electroplating was used to deposit the composite coating of (Zn–Ni) strengthened by Al{sub 2}O{sub 3} nanoparticles on mild steel plate. The effect of Al{sub 2}O{sub 3} fraction and ultrasonic irradiation on the properties of the composite coating was also investigated. Scanning electron microscopy and energy dispersive spectroscopy techniques were employed to characterize the morphology and composition of the coating. Topography and surface roughness were investigated by atomic force microscopy. Also in order to evaluate the mechanical properties of the coating micro hardness and wear tests were conducted. It was found that coating hardness was increased from 538 HV to 750 HV and friction coefficient was decreased from 0.588 to 0.392. Results revealed that tribological properties of coating could be improved significantly by using suitable ultrasonic intensity simultaneously with pulse plating. - Highlights: • SEM indicated on the elimination of cracks and pores when ultrasounds were used. • XRD result showed nano sized grains of Zn–Ni matrix was developed in this research. • Simultaneous pulse plating and ultrasonic conditions improved the properties of the coating. • A (Zn–Ni)/nano alumina uniform composite coating for especial applications was developed. • Micro hardness and wear behavior of the coating was modified by intensifying the ultrasound.

  15. The effect of zinc bath temperature on the morphology, texture and corrosion behaviour of industrially produced hot-dip galvanized coatings

    Directory of Open Access Journals (Sweden)

    A. Bakhtiari

    2014-03-01

    Full Text Available The purpose of this work is to identify the influence of zinc bath temperature on the morphology, texture and corrosion behavior of hot-dip galvanized coatings. Hot-dip galvanized samples were prepared at temperature in the range of 450-480 °C in steps of 10 °C, which is the conventional galvanizing temperature range in the galvanizing industries. The morphology of coatings was examined with optical microscopy and scanning electron microscopy (SEM. The composition of the coating layers was determined using energy dispersive spectroscopy (EDS analysis. The texture of the coatings was evaluated using X-ray diffraction. Corrosion behavior was performed using salt spray cabinet test and Tafel extrapolation test. From the experimental results, it was found that increasing the zinc bath temperature affects the morphology of the galvanized coatings provoking the appearance of cracks in the coating structure. These cracks prevent formation of a compact structure. In addition, it was concluded that (00.2 basal plane texture component was weakened by increasing the zinc bath temperature and, conversely, appearance of (10.1 prism component, (20.1 high angle pyramidal component and low angle component prevailed. Besides, coatings with strong (00.2 texture component and weaker (20.1 components have better corrosion resistance than the coatings with weak (00.2 and strong (20.1 texture components. Furthermore, corrosion resistance of the galvanized coatings was decreased by increasing the zinc bath temperature.

  16. 覆砂铁型铸造工艺生产ADI摩擦斜楔%ADI Oblique Wedge Produced with Resin Sand Coated-Iron Mold Casting Process

    Institute of Scientific and Technical Information of China (English)

    王彬; 鲍玉龙; 王德军

    2013-01-01

    The casting method and heat treatment process adopted for using resin sand coated-iron mold to produce ADI oblique wedge of railway vehicles was introduced. By adopting semi -pressurized gating system and filter to skim slag, choosing rational melting charge mixture ratio and the cored-wire injection nodularizing process, using salt bath isothermal quenching process, the hi-strength , hi-hardness and hi-toughness ADI castings with bainite + residual austenite as matrix were finally obtained.%介绍了采用覆砂铁型铸造生产火车用摩擦斜楔ADI铸件的铸造工艺和热处理工艺.通过采用半封闭式浇注系统和过滤网挡渣;选用合理的炉料配比及喂丝球化处理工艺;采用盐浴等温淬火工艺,最终获得以贝氏体+残余奥氏体为基体的高强度、高硬度及高韧性的ADI铸件.

  17. Single layer broadband anti-reflective coatings for plastic substrates produced by full wafer and roll-to-roll step-and-flash nano-imprint lithography

    NARCIS (Netherlands)

    Burghoorn, M.M.A.; Roosen-Melsen, D.A.; Riet, J.F.J. de; Sabik, S.; Vroon, Z.A.E.P.; Yakimets, I.; Buskens, P.J.P.

    2013-01-01

    Anti-reflective coatings (ARCs) are used to lower the reflection of light on the surface of a substrate. Here, we demonstrate that the two main drawbacks of moth eye-structured ARCs-i.e., the lack of suitable coating materials and a process for large area, high volume applications-can be largely

  18. Microstructure and corrosion performance of steam-based conversion coatings produced in the presence of TiO2 particles on aluminium alloys

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Gudla, Visweswara Chakravarthy; Jellesen, Morten Stendahl;

    2016-01-01

    The steam-based conversion coatings containing TiO2 particleswere prepared using a two-step process comprising of spin coating of particles onto an aluminiumsubstrate followed by a high-pressure steam treatment. Process has resulted in the formation of aluminium oxide layer (~1.3 μm thick) embedded...

  19. Microstructure and corrosion performance of steam-based conversion coatings produced in the presence of TiO2 particles on aluminium alloys

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Gudla, Visweswara Chakravarthy; Jellesen, Morten Stendahl

    2016-01-01

    The steam-based conversion coatings containing TiO2 particleswere prepared using a two-step process comprising of spin coating of particles onto an aluminiumsubstrate followed by a high-pressure steam treatment. Process has resulted in the formation of aluminium oxide layer (~1.3 μm thick) embedded...... to the coatings without TiO2 particles, while the shift in thepitting potential was a function of the steam treatment time and degree of particle incorporation into the oxide....

  20. AUTOCATALYTIC REDUCTION AND CHARACTERISTICS OF BORON-CONTAINING COATINGS

    Directory of Open Access Journals (Sweden)

    V. Covaliov

    2013-06-01

    Full Text Available The research results of the plating conditions, chemical composition and properties of Ni-B coatings and Ni-Re-B, Ni-Mo-B and Ni-W-B alloys are given. It was shown that introduction of alloying elements (Re, Мо and W in the composition of Ni-containing coatings modifies the catalytic activity of the alloys’ surface, with regard to the parallel reactions of dimethylamino-borane (DMAB heterogeneous hydrolysis, Ni reduction and evolving of the molecular hydrogen. It was found that with the increase in concentration of alloying element, boron content in the coatings is decreased to the trace amounts. The effect of alloys composition on hydrogen evolving overvoltage was studied. Due to the low overvoltage of hydrogen evolving (HE on the alloy Ni-Re-B surface (11 at.% Re, it can be used as electrode for hydrogen generation from water in the electrolytic cell with novel design and improved technical-economic indicators.

  1. Effect of Y2O3 Content on Microstructure of Gradient Bioceramic Composite Coating Produced by Wide-Band Laser Cladding

    Institute of Scientific and Technical Information of China (English)

    Liu Qibin; Zou Jianglong; Zheng Min; Dong Chuang

    2005-01-01

    To eliminate thermal stress and cracks in the process of laser cladding, a kind of bioceramic coating with gradient compositional design was prepared on the surface of Ti alloy by using wide-band laser cladding. And effect of Y2O3 content on gradient bioceramic composite coating was studied. The experimental results indicate that adding rare earth can refine grain. Different rare earth contents affect formation of HA and β-TCP in bioceramic coating. When the content of rare earth ranges from 0.4% to 0.6%, the active extent of rare earth in synthesizing HA and β-TCP is the best, which indicates that "monosodium glutamate" effect of rare earth plays a dominant role. However, when rare earth content is up to 0.8%, the amount of synthesizing HA and β-TCP in coating conversely goes down, which demonstrates that rare earth gradually losts its catalysis in manufacturing HA and β-TCP.

  2. Single Layer Broadband Anti-Reflective Coatings for Plastic Substrates Produced by Full Wafer and Roll-to-Roll Step-and-Flash Nano-Imprint Lithography

    National Research Council Canada - National Science Library

    Marieke Burghoorn; Dorrit Roosen-Melsen; Joris de Riet; Sami Sabik; Zeger Vroon; Iryna Yakimets; Pascal Buskens

    2013-01-01

    ...) and polycarbonate using wafer-by-wafer step-and-flash nano-imprint lithography (NIL). The reduction in reflection in the visible field achieved with these coatings was 3.5% and 4.0%, respectively...

  3. Microscopic phase-field simulation for influence of Ni-Mo fourth-nearest interaction energy on precipitation process of Ni75Al14Mo11 alloy%Ni-Mo四近邻作用能对Ni75Al14Mo11合金沉淀行为影响的微观相场

    Institute of Scientific and Technical Information of China (English)

    赵宇宏; 侯华; 任娟娜

    2012-01-01

    The influence of Ni-Mo fourth-nearest atomic interaction energy on ihe precipitation mechanism of Ni75AI14Mo11 alloy was investigated with the phase field model based on the microscopic diffusion equation. The structure evolution on atomic scale, the composition and long-range order parameters of the precipitates were analyzed to explore the ordering and clustering, atoms reverse precipitation and coarsening occurred in precipitation process of Ni75Al14Mo11 alloy. The results show that the increase of the nearest/the third Ni-Mo atomic interaction energy can promote the atoms clustering and ordering, yet restrain the later Nickel atoms reverse precipitation and coarsening; the influence of the second/the fourth Ni-Mo atomic interaction energy is contrary to that of the nearest/the third; and the influence of the outermost atomic interaction energy on clustering and ordering is the largest in the same condition.%基于微观扩散方程,采用微观离数格点相场法研究Ni-Mo原子间四近邻相互作用能对Ni75Al14Mo11合金沉淀过程微观机制的影响.通过原子尺度的结构演化图、表征浓度和有序度的成分序参数和长程序参数分析沉淀相的有序化、簇聚、镍原子反向析出及粗化行为等.研究结果表明:最近邻、第三近邻原子间作用能增大,可促进沉淀相的簇聚及有序化,但抑制后期镍基原子团簇的反向析出及粗化;次近邻、第四近邻原子间作用能增大的影响则与之相反;在相同条件下,外层作用能对沉淀相的有序化和簇聚影响最大.

  4. 遵义松林Ni-Mo矿区耕地土壤的镉砷污染及潜在生态风险评价%An Assessment on Contamination and Potential Ecological Risk of Cadmium and Arsenic in the Cultivated Soils Around the Ni-Mo Mining Area in Songlin, Zunyi, China

    Institute of Scientific and Technical Information of China (English)

    金昭贵; 周明忠

    2012-01-01

    The Ni-Mo mining area in Songlin, Zunyi, Guizhou is a type within the lower Cambrian Ni-Mo mineralization zone in South China. Therefore, assessing the environmental quality of the soils around the mining area is of important scientific and practical significances. The concentrations of cadmium and arsenic in cultivated soils around the Ni-Mo mining area in Songlin were analyzed using inductively coupled plasma mass spectrometry(ICP-MS) in this study. The result showed that the soils were characterized by high contents of cadmium (with an average of 1.82 mg·kg-1) and arsenic (with an average of 69.72 mg·kg-1), and that the concentrations of cadmium and arsenic in the soils of the study area were 12.68 times and 4.24 times higher than those of the background soils in Guizhou Province, respectively. In the present study, we evaluated the degree of contamination and potential ecological risk for the soils through geoaccumulation index and potential ecological risk index, respectively. It suggested that the soils around the Ni-Mo mining area in Songlin, Zunyi, Guizhou had been contaminated by cadmium (most of the soil samples with moderate to heavy pollution) and arsenic (with moderate pollution dominantly). It also indicated that the studied soils had relatively high potential ecological risk caused by cadmium and arsenic (with moderate to high potential ecological risk levels). Therefore, further researches on remediation for the contaminated soils deserve to be carried out.%贵州遵义松林Ni-Mo矿区为华南下寒武统黑色页岩Ni-Mo矿化带中的典型矿区之一,对与其矿产资源开采活动相关的土壤环境质量评价具有重要的科学及实际意义.以松林Ni-Mo矿区耕地土壤为研究对象,采用ICP-MS方法分析其中镉和砷的含量.分析结果显示,该矿区耕地土壤中镉和砷的平均含量分别为1.82 mg· kg-1和69.72 mg·kg-1,具有高镉、砷含量特征.运用地质累积指数和潜在生态风险指数分别

  5. Laser Surface Treatment of Hydro and Thermal Power Plant Components and Their Coatings: A Review and Recent Findings

    Science.gov (United States)

    Mann, B. S.

    2015-11-01

    High-power diode laser (HPDL) surface modification of hydro and thermal power plant components is of the utmost importance to minimize their damages occurring due to cavitation erosion, water droplet erosion, and particle erosion (CE, WDE, and PE). Special emphasis is given on the HPDL surface treatment of martensitic and precipitate-hardened stainless steels, Ti6Al4V alloy, plasma ion nitro-carburized layers, high pressure high velocity oxy-fuel and twin-wire arc sprayed coatings. WDE test results of all these materials and coatings in `untreated' and `HPDL- treated at 1550 °C' conditions, up to 8.55 million cycles, are already available. Their WDE testing was further continued up to 10.43 million cycles. The X20Cr13 and X10CrNiMoV1222, the most common martensitic stainless steels used in hydro and thermal power plants, were HPDL surface treated at higher temperature (1650 °C) and their WDE test results were also obtained up to 10.43 million cycles. It is observed that the increased HPDL surface temperature from 1550 to 1650 °C has resulted in significant improvement in their WDE resistances because of increased martensitic (ά) phase at higher temperature. After conducting long-range WDE tests, the correlation of CE, WDE, and PE resistances of these materials and protective coatings with their mechanical properties such as fracture toughness and microhardness product, ultimate resilience, modified resilience, and ultimate modified resilience has been reviewed and discussed. One of the edges of a 500 MW low pressure steam turbine moving blade (X10CrNiMoV1222 stainless steel) was HPDL surface treated at 1550 °C and its radii of curvatures and deflections were measured. These were compared with the data available earlier from a flat rectangular sample of similar composition and identical HPDL surface temperature.

  6. Influence of powder particle injection velocity on the microstructure of Al-12Si/SiCp coatings produced by laser cladding

    NARCIS (Netherlands)

    Anandkumar, R.; Almeida, A.; Vilar, R.; Ocelik, V.; De Hosson, J. Th M.

    2009-01-01

    The influence of powder particle injection velocity on the microstructure of coatings consisting of an Al-Si matrix reinforced with SiC particles prepared by laser cladding from mixtures of powders of Al-12 wt.% Si alloy and SiC was investigated both experimentally and by modeling. At low injection

  7. Development of a novel carbon-coating strategy for producing core-shell structured carbon coated LiFePO4 for an improved Li-ion battery performance.

    Science.gov (United States)

    Pratheeksha, Parakandy Muzhikara; Mohan, Erabhoina Hari; Sarada, Bulusu Venkata; Ramakrishna, Mantripragada; Hembram, Kalyan; Srinivas, Pulakhandam Veera Venkata; Daniel, Paul Joseph; Rao, Tata Narasinga; Anandan, Srinivasan

    2016-12-21

    In the present study, LiFePO4 (LFP) has been synthesized using a flame spray pyrolysis unit followed by carbon coating on LFP using a novel strategy of dehydration assisted polymerization process (DAP) in order to improve its electronic conductivity. Characterization studies revealed the presence of a pure LFP structure and the formation of a thin, uniform and graphitic carbon layer with a thickness of 6-8 nm on the surface of the LFP. A carbon coated LFP with 3 wt% of carbon, using a DAP process, delivered a specific capacity of 167 mA h g(-1) at a 0.1C rate, whereas LFP carbon coated by a carbothermal process (CLFP-C) delivered a capacity of 145 mA h g(-1) at 0.1C. Further carbon coated LFP by the DAP exhibited a good rate capability and cyclic stability. The enhanced electrochemical performance of C-LFP by DAP is attributed to the presence of a uniform, thin and ordered graphitic carbon layer with a core-shell structure, which greatly increased the electronic conductivity of LFP and thereby showed an improved electro-chemical performance. Interestingly, the developed carbon coating process has been extended to synthesize a bulk quantity (0.5 kg) of carbon coated LFP under optimized experimental conditions as a part of up-scaling and the resulting material electro-chemical performance has been evaluated and compared with commercial electrode materials. Bulk C-LFP showed a capacity of 131 mA h g(-1) and 87 mA h g(-1) at a rate of 1C and at 10C, respectively, illustrating that the developed DAP process greatly improved the electrochemical performance of LFP in terms of rate capability and cyclic stability, not only during the lab scale synthesis but also during the large scale synthesis. Benchmark studies concluded that the electro-chemical performance of C-LFP by DAP is comparable with that of TODA LFP and better than that of UNTPL LFP. The DAP process developed in the present study can be extended to other electrode materials as well.

  8. High Power Diode Laser-Treated HP-HVOF and Twin Wire Arc-Sprayed Coatings for Fossil Fuel Power Plants

    Science.gov (United States)

    Mann, B. S.

    2013-08-01

    This article deals with high power diode laser (HPDL) surface modification of twin wire arc-sprayed (TWAS) and high pressure high velocity oxy-fuel (HP-HVOF) coatings to combat solid particle erosion occurring in fossil fuel power plants. To overcome solid particle impact wear above 673 K, Cr3C2-NiCr-, Cr3C2-CoNiCrAlY-, and WC-CrC-Ni-based HVOF coatings are used. WC-CoCr-based HVOF coatings are generally used below 673 K. Twin wire arc (TWA) spraying of Tafa 140 MXC and SHS 7170 cored wires is used for a wide range of applications for a temperature up to 1073 K. Laser surface modification of high chromium stainless steels for steam valve components and LPST blades is carried out regularly. TWA spraying using SHS 7170 cored wire, HP-HVOF coating using WC-CoCr powder, Ti6Al4V alloy, and high chromium stainless steels (X20Cr13, AISI 410, X10CrNiMoV1222, 13Cr4Ni, 17Cr4Ni) were selected in the present study. Using robotically controlled parameters, HPDL surface treatments of TWAS-coated high strength X10CrNiMoV1222 stainless steel and HP-HVOF-coated AISI 410 stainless steel samples were carried out and these were compared with HPDL-treated high chromium stainless steels and titanium alloy for high energy particle impact wear (HEPIW) resistance. The HPDL surface treatment of the coatings has improved the HEPIW resistance manifold. The improvement in HPDL-treated stainless steels and titanium alloys is marginal and it is not comparable with that of HPDL-treated coatings. These coatings were also compared with "as-sprayed" coatings for fracture toughness, microhardness, microstructure, and phase analyses. The HEPIW resistance has a strong relationship with the product of fracture toughness and microhardness of the HPDL-treated HP-HVOF and TWAS SHS 7170 coatings. This development opens up a possibility of using HPDL surface treatments in specialized areas where the problem of HEPIW is very severe. The HEPIW resistance of HPDL-treated high chromium stainless steels and

  9. Effect of surfactant concentration in the electrolyte on the tribological properties of nickel-tungsten carbide composite coatings produced by pulse electro co-deposition

    Science.gov (United States)

    Kartal, Muhammet; Uysal, Mehmet; Gul, Harun; Alp, Ahmet; Akbulut, Hatem

    2015-11-01

    A nickel plating bath containing WC particles was used to obtain hard and wear-resistant particle reinforced Ni/WC MMCs on steel surfaces for anti-wear applications. Copper substrates were used for electro co-deposition of Ni matrix/WC with the particle size of nickel films were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The effects of the surfactant on the zeta potential, co-deposition and distribution of WC particles in the nickel matrix, as well as the tribological properties of composite coatings were also investigated. The tribological behaviors of the electrodeposited WC composite coatings sliding against M50 steel ball (Ø 10 mm) were examined on a CSM Instrument. All friction and wear tests were performed without lubrication at room temperature and in the ambient air (relative humidity 55-65%).

  10. Lead-Free Sn-Ce-O Composite Coating on Cu Produced by Pulse Electrodeposition from an Aqueous Acidic Sulfate Electrolyte

    Science.gov (United States)

    Sharma, Ashutosh; Das, Karabi; Das, Siddhartha

    2017-10-01

    Pulse-electrodeposited Sn-Ce-O composite solder coatings were synthesized on a Cu substrate from an aqueous acidic solution containing stannous sulfate (SnSO4·3H2O), sulfuric acid (H2SO4), and Triton X-100 as an additive. The codeposition was achieved by adding nano-cerium oxide powder in varying concentrations from 5 g/L to 20 g/L into the electrolytic bath. Microstructural characterization was carried out using x-ray diffraction (XRD), scanning electron microscopy, and transmission electron microscopy. The XRD analysis showed that the deposits consist mainly of tetragonal β (Sn) with reduced cerium oxide species. The composite coatings thus obtained exhibit a smaller grain size, possess higher microhardness, and a lower melting point than the monolithic Sn coating. The electrical resistivity of the developed composites increases, however, but lies within the permissible limits for current lead-free solder applications. Also, an optimum balance of properties in terms of microhardness, adhesion, melting point and resistivity can be obtained with 0.9 wt.% cerium oxide in the Sn matrix, which enables potential applications in solder joints and packaging.

  11. Immunodetection of Triticum mosaic virus by DAS- and DAC-ELISA using antibodies produced against coat protein expressed in Escherichia coli: potential for high-throughput diagnostic methods.

    Science.gov (United States)

    Tatineni, Satyanarayana; Sarath, Gautam; Seifers, Dallas; French, Roy

    2013-04-01

    Triticum mosaic virus (TriMV), an economically important virus infecting wheat in the Great Plains region of the USA, is the type species of the Poacevirus genus in the family Potyviridae. Sensitive and high-throughput serology-based detection methods are crucial for the management of TriMV and germplasm screening in wheat breeding programs. In this study, TriMV coat protein (CP) was expressed in Escherichia coli, and polyclonal antibodies were generated against purified soluble native form recombinant CP (rCP) in rabbits. Specificity and sensitivity of resulting antibodies were tested in Western immuno-blot and enzyme-linked immunosorbent assays (ELISA). In direct antigen coating (DAC)-ELISA, antibodies reacted specifically, beyond 1:20,000 dilution with TriMV in crude sap, but not with healthy extracts, and antiserum at a 1:10,000 dilution detected TriMV in crude sap up to 1:4860 dilution. Notably, rabbit anti-TriMV IgG and anti-TriMV IgG-alkaline phosphatase conjugate reacted positively with native virions in crude sap in a double antibody sandwich-ELISA, suggesting that these antibodies can be used as coating antibodies which is crucial for any 'sandwich' type of assays. Finally, the recombinant antibodies reacted positively in ELISA with representative TriMV isolates collected from fields, suggesting that antibodies generated against rCP can be used for sensitive, large-scale, and broad-spectrum detection of TriMV.

  12. Controlled Thermal Expansion Coat for Thermal Barrier Coatings

    Science.gov (United States)

    Brindley, William J. (Inventor); Miller, Robert A. (Inventor); Aikin, Beverly J. M. (Inventor)

    1999-01-01

    A improved thermal barrier coating and method for producing and applying such is disclosed herein. The thermal barrier coating includes a high temperature substrate, a first bond coat layer applied to the substrate of MCrAlX, and a second bond coat layer of MCrAlX with particles of a particulate dispersed throughout the MCrAlX and the preferred particulate is Al2O3. The particles of the particulate dispersed throughout the second bond coat layer preferably have a diameter of less then the height of the peaks of the second bond coat layer, or a diameter of less than 5 microns. The method of producing the second bond coat layer may either include the steps of mechanical alloying of particles throughout the second bond coat layer, attrition milling the particles of the particulate throughout the second bond coat layer, or using electrophoresis to disperse the particles throughout the second bond coat layer. In the preferred embodiment of the invention, the first bond coat layer is applied to the substrate, and then the second bond coat layer is thermally sprayed onto the first bond coat layer. Further, in a preferred embodiment of die invention, a ceramic insulating layer covers the second bond coat layer.

  13. Effect of particle concentration on the structure and tribological properties of submicron particle SiC reinforced Ni metal matrix composite (MMC) coatings produced by electrodeposition

    Energy Technology Data Exchange (ETDEWEB)

    Guel, H., E-mail: harungul@duzce.edu.tr [Duzce University, Gumusova Vocational School, Department of Metallurgy, 81850, Duzce (Turkey); K Latin-Small-Letter-Dotless-I l Latin-Small-Letter-Dotless-I c, F.; Uysal, M.; Aslan, S.; Alp, A.; Akbulut, H. [Sakarya University, Engineering Faculty, Department of Metallurgical and Materials Engineering, Esentepe Campus, 54187, Sakarya (Turkey)

    2012-03-01

    In the present work, a nickel sulfate bath containing SiC submicron particles between 100 and 1000 nm was used as the plating electrolyte. The aim of this work is to obtain Ni-SiC metal matrix composites (MMCs) reinforced with submicron particles on steel surfaces with high hardness and wear resistance for using in anti-wear applications such as dies, tools and working parts for automobiles and vehicles. The influence of the SiC content in the electrolyte on particle distribution, microhardness and wear resistance of nano-composite coatings was studied. During the electroplating process, the proper stirring speed was also determined for sub-micron SiC deposition with Ni matrix. The Ni films were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The depositions were controlled to obtain a specific thickness (between 50 and 200 {mu}m) and volume fraction of the particles in the matrix (between 0.02 and 0.10). The hardness of the coatings was measured to be 280-571 HV depending on the particle volume in the Ni matrix. The tribological behaviors of the electrodeposited SiC nanocomposite coatings sliding against an M50 steel ball (O 10 mm) were examined on a tribometer. All the friction and wear tests were performed without lubrication at room temperature and in the ambient air (with a relative humidity of 55-65%). The results showed that the wear resistance of the nanocomposites was approximately 2-2.2 times more than those of unreinforced Ni.

  14. Effect of Heat Treatment on the Structural Properties of TiO2 Films Produced by Sol-Gel Spin Coating Technique

    Science.gov (United States)

    Nebi, M.; Peker, D.

    2016-10-01

    Due to have superior properties as fotocatalyst and have wide band gap, TiO2 thin films often investigated by researchers and used by technological applications widely. In this study TiO2 films were deposited on glass substrate by Sol-Gel Spin Coating Technic. TiO2 films were deposited at different number of layer and then annealed at 400o C, 500o C, and 600o C in air. Effect of anneal temperature to structural properties were investigated by XRD analysis. It was observed by the light of XRD results that the structural properties of films had changed by anneal temperature.

  15. New nano-sized Al2O3-BN coating 3Y-TZP ceramic composites for CAD/CAM-produced all-ceramic dental restorations. Part I. Fabrication of powders.

    Science.gov (United States)

    Yang, Se Fei; Yang, Li Qiang; Jin, Zhi Hao; Guo, Tian Wen; Wang, Lei; Liu, Hong Chen

    2009-06-01

    Partially sintered 3 mol % yttria-stabilized tetragonal zirconium dioxide (ZrO(2), zirconia) polycrystal (3Y-TZP) ceramics are used in dental posterior restorations with computer-aided design-computer-aided manufacturing (CAD/CAM) techniques. High strength is acquired after sintering, but shape distortion of preshaped compacts during their sintering is inevitable. The aim of this study is to fabricate new machinable ceramic composites with strong mechanical properties that are fit for all-ceramic dental restorations. Aluminum oxide (Al(2)O(3))-coated 3Y-TZP powders were first prepared by the heterogeneous precipitation method starting with 3Y-TZP, Al(NO(3))(3) . 9H(2)O, and ammonia, then amorphous boron nitride (BN) was produced and the as-received composite powders were coated via in situ reaction with boric acid and urea. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) were used to analyze the status of Al(2)O(3)-BN on the surface of the 3Y-TZP particles. TEM micrographs show an abundance of Al(2)O(3) particles and amorphous BN appearing uniformly on the surface of the 3Y-TZP particles after the coating process. The size of the Al(2)O(3) particles is about 20 nm. The XRD pattern shows clearly the peak of amorphous BN among the peaks of ZrO(2).

  16. Effect of H{sub 2}S partial pressure on the HDS of dibenzothiophene and 4,6-dimethyldibenzothiophene over sulfided NiMoP/Al{sub 2}O{sub 3} and CoMoP/Al{sub 2}O{sub 3} catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Rabarihoela-Rakotovao, V.; Brunet, S.; Perot, G. [UMR CNRS 6503, Catalyse en Chimie Organique, Universite de Poitiers, 40 avenue du Recteur Pineau, 86022 Poitiers, Cedex (France); Diehl, F. [Institut Francais du Petrole, IFP-Lyon, Catalysis and Separation Division, Heterogeneous Catalysis Department, BP 3, 69390 Vernaison (France)

    2006-06-07

    The effect of hydrogen sulfide (H{sub 2}S) partial pressure on the hydrodesulfurization (HDS) of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (46DMDBT) was studied over commercial NiMoP/Al{sub 2}O{sub 3} and CoMoP/Al{sub 2}O{sub 3} catalysts under conditions close to those commonly used in the hydrotreating of diesel fuels (280 or 340{sup o}C; total pressure between 2.5 and 5.5MPa). The sulfur compounds diluted in n-heptane were in proportions representative of those found in diesel fuels (0.0014MPa of DBT or 46DMDBT, 0.0058-0.1MPa of H{sub 2}S generated from dimethyldisulfide). A significant negative effect of H{sub 2}S on the HDS of the dibenzothiophenes (DBT and 46DMDBT) was observed whatever the total pressure (2.5-5.5MPa) and the catalyst used. However, the reactivity of DBT was more reduced than that of 46DMDBT. Moreover, the 'direct desulfurization pathway' (DDS) of both reactants was more inhibited by H{sub 2}S than the so-called 'hydrogenation pathway' (HYD) over the two catalysts. It was also found that the NiMoP/Al{sub 2}O{sub 3} catalyst was more sensitive to H{sub 2}S than its CoMoP/Al{sub 2}O{sub 3} counterpart whatever the experimental conditions. Several hypotheses were considered and discussed to explain these findings: specific centres for each of the two reactions (DDS and HYD) or centres being similar in nature (sulfur vacancies associated to sulfur anions) but which would differ in their acid-base properties. It was also suggested that the centres could be identical but that DDS and HYD could have different rate-limiting steps which would not involve the same part of the dual site so that their sensitivity to H{sub 2}S would be different. (author)

  17. 载体的酸性和钠含量对Ni-Mo催化剂加氢脱硫性能的影响%THE EFFECT OF ACIDITY AND SODIUM CONTENT OF SUPPORT ON THE HDS PERFORMACE OF Ni-Mo CATALYSTS

    Institute of Scientific and Technical Information of China (English)

    姜凤华; 王安杰; 胡永康; 任靖

    2011-01-01

    A series of Ni-Mo HDS catalysts were prepared by using various supports including MCM-41, NaMCM-41, HY, NaY and their mechanical mixtures. The supports and the catalysts were characterized by TPR, UV-Vis, ICP-AES and IR. The HDS activities of these prepared catalysts were evaluated using dibenzothiophene (DBT) as model compound to study the effect of support acidity and sodium content on the HDS activity of catalyst. It is found that the HDS activities of these catalysts are related to the Br(o)nsted acidity and sodium contents of the supports: Br(o)nsted acidity has a positive effect on the HDS activity of the supported Ni-Mo catalysts while Na+ has a negative effect. Furthermore, it seems that some synergetic effects exist between the acid sites of support and the active components linking by spillover hydrogen as shown from the results of TPR characterization and HDS evaluation.%用MCM-41和Na交换的MCM-41(NaMCM-41)以及它们与NaY和HY沸石的机械混合物为载体负载Ni-Mo制备了加氢脱硫(HDS)催化剂,用ICP-AES、吡啶吸附红外、UV-Vis、TPR等对载体和所制备的催化剂进行了表征.以二苯并噻吩(DBT)为模型化合物评价了催化剂的HDS活性,考察了载体的酸性和Na含量对催化剂HDS活性的影响.发现Ni-Mo催化剂的HDS活性与载体的Na+含量和B酸量有关,而与L酸量关系不大.通过催化剂的HDS反应和TPR表征结果,发现在载体酸中心和活性组分之间可能存在着以溢流氢为纽带的协同作用.

  18. Reduction of hematite with ethanol to produce magnetic nanoparticles of Fe3O4, Fe1 - x O or Fe0 coated with carbon

    Science.gov (United States)

    Tristão, Juliana C.; Ardisson, José D.; Sansiviero, Maria Terezinha C.; Lago, Rochel M.

    2010-01-01

    The production of magnetic nanoparticles of Fe3O4 or Fe0 coated with carbon and carbon nanotubes was investigated by the reduction of hematite with ethanol in a Temperature Programmed Reaction up to 950°C. XRD and Mössbauer measurements showed after reaction at 350°C the partial reduction of hematite to magnetite. At 600°C the hematite is completely reduced to magnetite (59%), wüstite (39%) and metallic iron (7%). At higher temperatures, carbide and metallic iron are the only phases present. TG weight losses suggested the formation of 3-56 wt.% carbon deposits after reaction with ethanol. It was observed by SEM images a high concentration of nanometric carbon filaments on the material surface. BET analyses showed a slight increase in the surface area after reaction. These materials have potential application as catalyst support and removal of spilled oil contaminants.

  19. 覆砂铁型铸造生产球铁法兰主轴%Main Bearing with Flange Produced by Permanent Die Coated with Sand

    Institute of Scientific and Technical Information of China (English)

    董琪; 顾厚军; 史传岳; 钟晓斌

    2014-01-01

    把原粘土砂湿型生产法兰主轴铸件的工艺改为覆砂铁型工艺,解决了内部缩松等一系列缺陷问题。与原工艺相比,实现了覆砂铁型工艺的“多、快、好、省”。%Problems as defects of inner shrinkage etc in castings of main bearing with flange have been solved when the former technology of clay green sand molding has had been changed to technology of permanent die coated with sand of which the advantages have been much output, quicker, better and cost saved.

  20. Application of a Coated Film Catalyst Layer Model to a High Temperature Polymer Electrolyte Membrane Fuel Cell with Low Catalyst Loading Produced by Reactive Spray Deposition Technology

    Directory of Open Access Journals (Sweden)

    Timothy D. Myles

    2015-10-01

    Full Text Available In this study, a semi-empirical model is presented that correlates to previously obtained experimental overpotential data for a high temperature polymer electrolyte membrane fuel cell (HT-PEMFC. The goal is to reinforce the understanding of the performance of the cell from a modeling perspective. The HT-PEMFC membrane electrode assemblies (MEAs were constructed utilizing an 85 wt. % phosphoric acid doped Advent TPS® membranes for the electrolyte and gas diffusion electrodes (GDEs manufactured by Reactive Spray Deposition Technology (RSDT. MEAs with varying ratios of PTFE binder to carbon support material (I/C ratio were manufactured and their performance at various operating temperatures was recorded. The semi-empirical model derivation was based on the coated film catalyst layer approach and was calibrated to the experimental data by a least squares method. The behavior of important physical parameters as a function of I/C ratio and operating temperature were explored.

  1. Investigation of hydrogen evolution activity for the nickel, nickel-molybdenum nickel-graphite composite and nickel-reduced graphene oxide composite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Jinlong, Lv, E-mail: ljlbuaa@126.com [Beijing Key Laboratory of Fine Ceramics, Institute of Nuclear and New Energy Technology, Tsinghua University, Zhongguancun Street, Haidian District, Beijing 100084 (China); State Key Lab of New Ceramic and Fine Processing, Tsinghua University, Beijing 100084 (China); Tongxiang, Liang; Chen, Wang [Beijing Key Laboratory of Fine Ceramics, Institute of Nuclear and New Energy Technology, Tsinghua University, Zhongguancun Street, Haidian District, Beijing 100084 (China); State Key Lab of New Ceramic and Fine Processing, Tsinghua University, Beijing 100084 (China)

    2016-03-15

    Graphical abstract: - Highlights: • Improved HER efficiency of Ni-Mo coatings was attributed to ‘cauliflower’ like microstructure. • RGO in nickel-RGO composite coating promoted refined grain and facilitated HER. • Synergistic effect between nickel and RGO facilitated HER due to large specific surface of RGO. - Abstract: The nickel, nickel-molybdenum alloy, nickel-graphite and nickel-reduced graphene oxide composite coatings were obtained by the electrodeposition technique from a nickel sulfate bath. Nanocrystalline molybdenum, graphite and reduced graphene oxide in nickel coatings promoted hydrogen evolution reaction in 0.5 M H{sub 2}SO{sub 4} solution at room temperature. However, the nickel-reduced graphene oxide composite coating exhibited the highest electrocatalytic activity for the hydrogen evolution reaction in 0.5 M H{sub 2}SO{sub 4} solution at room temperature. A large number of gaps between ‘cauliflower’ like grains could decrease effective area for hydrogen evolution reaction in slight amorphous nickel-molybdenum alloy. The synergistic effect between nickel and reduced graphene oxide promoted hydrogen evolution, moreover, refined grain in nickel-reduced graphene oxide composite coating and large specific surface of reduced graphene oxide also facilitated hydrogen evolution reaction.

  2. Thickness Dependent Structural and Dielectric Properties of Calcium Copper Titanate Thin Films Produced by Spin-Coating Method for Microelectronic Devices

    Science.gov (United States)

    Thiruramanathan, P.; Sankar, S.; Marikani, A.; Madhavan, D.; Sharma, Sanjeev K.

    2017-03-01

    Calcium copper titanate (CaCu3Ti4O12, CCTO) thin films have been deposited on platinized silicon [(111)Pt/Ti/SiO2/Si] substrate through a sol-gel spin coating technique and annealed at 600-900°C with a variation of 100°C per sample for 3 h. The activation energy for crystalline growth, as well as optimal annealing temperature (900°C) of the CCTO crystallites was studied by x-ray diffraction analysis (XRD). Thickness dependent structural, morphological, and optical properties of CCTO thin films were observed. The field emission scanning electron microscopy (FE-SEM) verified that the CCTO thin films are uniform, fully covered, densely packed, and the particle size was found to be increased with film thickness. Meanwhile, quantitative analysis of dielectric properties (interfacial capacitance, dead layers, and bulk dielectric constant) of CCTO thin film with metal-insulator-metal (M-I-M) structures has been investigated systematically using a series capacitor model. Room temperature dielectric properties of all the samples exhibit dispersion at low frequencies, which can be explained based on Maxwell-Wagner two-layer models and Koop's theory. It was found that the 483 nm thick CCTO film represents a high dielectric constant (ɛ r = 3334), low loss (tan δ = 3.54), capacitance (C = 4951 nF), which might satisfy the requirements of embedded capacitor.

  3. Thickness Dependent Structural and Dielectric Properties of Calcium Copper Titanate Thin Films Produced by Spin-Coating Method for Microelectronic Devices

    Science.gov (United States)

    Thiruramanathan, P.; Sankar, S.; Marikani, A.; Madhavan, D.; Sharma, Sanjeev K.

    2017-07-01

    Calcium copper titanate (CaCu3Ti4O12, CCTO) thin films have been deposited on platinized silicon [(111)Pt/Ti/SiO2/Si] substrate through a sol-gel spin coating technique and annealed at 600-900°C with a variation of 100°C per sample for 3 h. The activation energy for crystalline growth, as well as optimal annealing temperature (900°C) of the CCTO crystallites was studied by x-ray diffraction analysis (XRD). Thickness dependent structural, morphological, and optical properties of CCTO thin films were observed. The field emission scanning electron microscopy (FE-SEM) verified that the CCTO thin films are uniform, fully covered, densely packed, and the particle size was found to be increased with film thickness. Meanwhile, quantitative analysis of dielectric properties (interfacial capacitance, dead layers, and bulk dielectric constant) of CCTO thin film with metal-insulator-metal (M-I-M) structures has been investigated systematically using a series capacitor model. Room temperature dielectric properties of all the samples exhibit dispersion at low frequencies, which can be explained based on Maxwell-Wagner two-layer models and Koop's theory. It was found that the 483 nm thick CCTO film represents a high dielectric constant ( ɛ r = 3334), low loss (tan δ = 3.54), capacitance ( C = 4951 nF), which might satisfy the requirements of embedded capacitor.

  4. Investigations of the corrosion fatigue behaviour at a super pure martensitic stainless steel X5CrNiCuNb 17 4 PH in comparison to the soft martensitic stainless steel X4CrNiMo 16 5 1 ESR in chloride containing aqueous media. Pt. 2. Corrosion fatigue tests and crack initiation mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt-Thomas, K.G.; Happle, T.; Wunderlich, R.

    1989-07-01

    The following report concerns the study of the corrosion fatigue behaviour of the soft martensitic steel X4CrNiMo 16 5 1 ESR and the precipitation hardened X5CrNiCuNb 17 4 PH in sodium solution in the temperature range between 20/sup 0/ and 150/sup 0/C and the determination of their general corrosion properties and the mechanism of crack propagation. Their corrosion fatigue limits were compared with each other. A comparison was also made between an electro-slag-remelted soft martensitic steel and a charge without an ESR aftertreatment. Microfractographical fracture and crack path investigation were carried out for interpretation of the experimental results. It was observed that in both super pure steels (soft martensitic and precipitation hardened) the oxidic inclusions are not responsible for the crack initiation, as it was found in the non ESR treated steels. In the 17-4 PH steel copper containing inclusions in the crack initiation areas were observed. In concentrated sodium solution pitting corrosion was found at both steels. (orig.).

  5. Thermoplastic coating of carbon fibers

    Science.gov (United States)

    Edie, D. D.; Lickfield, G. C.; Drews, M. J.; Ellison, M. S.; Gantt, B. W.

    1989-01-01

    A process is being developed which evenly coats individual carbon fibers with thermoplastic polymers. In this novel, continuous coating process, the fiber tow bundle is first spread cover a series of convex rollers and then evenly coated with a fine powder of thermoplastic matrix polymer. Next, the fiber is heated internally by passing direct current through the powder coated fiber. The direct current is controlled to allow the carbon fiber temperature to slightly exceed the flow temperature of the matrix polymer. Analysis of the thermoplastic coated carbon fiber tows produced using this continuous process indicates that 30 to 70 vol pct fiber prepregs can be obtained.

  6. Thermoplastic coating of carbon fibers

    Science.gov (United States)

    Edie, D. D.; Lickfield, G. C.; Drews, M. J.; Ellison, M. S.; Gantt, B. W.

    1989-01-01

    A process is being developed which evenly coats individual carbon fibers with thermoplastic polymers. In this novel, continuous coating process, the fiber tow bundle is first spread cover a series of convex rollers and then evenly coated with a fine powder of thermoplastic matrix polymer. Next, the fiber is heated internally by passing direct current through the powder coated fiber. The direct current is controlled to allow the carbon fiber temperature to slightly exceed the flow temperature of the matrix polymer. Analysis of the thermoplastic coated carbon fiber tows produced using this continuous process indicates that 30 to 70 vol pct fiber prepregs can be obtained.

  7. Natural-oxide solar-collector coatings

    Science.gov (United States)

    Krupnick, A. C.; Roberts, M. L.; Sharpe, M. H.

    1979-01-01

    Optically selective coatings for solar collectors are produced by thermally treating stainless steel in furnace after series of cleaning and soaking operations. Coatings have withstood 18-month exposure tests at 100 percent relative humidity and temperatures of 95 F. Room temperature coatings are valuable as they are inexpensive to produce, highly production oriented, and environmentally stable.

  8. Chitin-based coatings

    OpenAIRE

    1995-01-01

    A chitosan starting material is combined with a dilute organic acid to produce a chitosonium ion complex. The chitosonium ion complex is then cast, sprayed, extruded, or otherwise processed to produce filaments, coatings, fibers, or the like. Heat is then used to convert the chitosonium ion complex into a N-(C.sub.1-30)acyl glucose amine polymer.

  9. 解淀粉芽孢杆菌BI2产抑菌物质的新型种衣剂的研制%A Novel Seed Coating Formula with Antifungal Substances Produced by Bacillus amyloliquefaciens BI2

    Institute of Scientific and Technical Information of China (English)

    王亚军; 李昆; 王德培

    2015-01-01

    The antifungal substances produced from Bacillus amyloliquefaciens BI2,were for the first time used asactive ingredients in seed coating. The fermented broth containing antifungal substances was ultrafiltered and freeze-dried to form lyophilized powder,and then mixed with composite film-forming agent solution. Finally,peanut seeds were coated with this kind of seed coating containing antifungal substances. The results showed that the best volume ratio of 4%, polyvinyl alco-hol(PVA)to 1.5%, sodium carboxymethyl cellulose(CMC-Na)was 5:1,which is the best film former recipe in seed coating,and it has no significant effect on seed germination potential and germination rate. The pH stability andthermal stability of the lyophilized powder of the fermentated broth containing antifungal substances are good. The MIC of the pow-der to inhibitAspergillus flavus spore germination is 1.92,mg/mL. When the content of that powder in the film former reaches 4,mg/mL,A. flavuswas completely inhibited.%将解淀粉芽孢杆菌BI2发酵所产抑菌物质作为新型种衣剂的有效成分与研制的复合型成膜剂溶液混合,制成可抑制黄曲霉孢子萌发的花生种子包衣.结果表明,选用 4%,聚乙烯醇(PVA)与 1.5%,羧甲基纤维素钠(CMC-Na)以体积比 5:1 混合作为种子包衣最佳成膜剂配方,经过包衣后对花生种子的发芽势和发芽率没有显著影响.含有抑菌物质的发酵液冻干粉的 pH 稳定性和热稳定性均较好.发酵液冻干粉抑制黄曲霉孢子萌发的最小质量浓度为1.92,mg/mL.在与花生种子混合时,发酵液冻干粉在成膜剂中的含量达到4,mg/mL时,黄曲霉完全被抑制.

  10. Spray-Deposited Superconductor/Polymer Coatings

    Science.gov (United States)

    Wise, Stephanie A.; Tran, Sang Q.; Hooker, Matthew W.

    1993-01-01

    Coatings that exhibit the Meissner effect formed at relatively low temperature. High-temperature-superconductor/polymer coatings that exhibit Meissner effect deposited onto components in variety of shapes and materials. Simple, readily available equipment needed in coating process, mean coatings produced economically. Coatings used to keep magnetic fields away from electronic circuits in such cryogenic applications as magnetic resonance imaging and detection of infrared, and in magnetic suspensions to provide levitation and/or damping of vibrations.

  11. XPS-nanocharacterization of organic layers electrochemically grafted on the surface of SnO2 thin films to produce a new hybrid material coating

    Science.gov (United States)

    Drevet, R.; Dragoé, D.; Barthés-Labrousse, M. G.; Chaussé, A.; Andrieux, M.

    2016-10-01

    This work presents the synthesis and the characterization of hybrid material thin films obtained by the combination of two processes. The electrochemical grafting of organic layers made of carboxyphenyl moieties is carried out from the reduction of a diazonium salt on tin dioxide (SnO2) thin films previously deposited on Si substrates by metal organic chemical vapor deposition (MOCVD). Since the MOCVD experimental parameters impact the crystal growth of the SnO2 layer (i.e. its morphology and its texturation), various electrochemical grafting models can occur, producing different hybrid materials. In order to evidence the efficiency of the electrochemical grafting of the carboxyphenyl moieties, X-ray Photoelectron Spectroscopy (XPS) is used to characterize the first nanometers in depth of the synthesized hybrid material layer. Then three electrochemical grafting models are proposed.

  12. Methods for Coating Particulate Material

    Science.gov (United States)

    Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)

    2013-01-01

    Methods and apparatus for coating particulate material are provided. The apparatus includes a vessel having a top and a bottom, a vertically extending conduit having an inlet in the vessel and an outlet outside of the vessel, a first fluid inlet in the bottom of the vessel for introducing a transfer fluid, a second fluid inlet in the bottom of the vessel for introducing a coating fluid, and a fluid outlet from the vessel. The method includes steps of agitating a material, contacting the material with a coating material, and drying the coating material to produce a coated material. The invention may be adapted to coat aerogel beads, among other materials. A coated aerogel bead and an aerogel-based insulation material are also disclosed.

  13. Effect of V addition on the hardness, adherence and friction coefficient of VC coatings produced by thermo-reactive diffusion deposition

    Directory of Open Access Journals (Sweden)

    Fredy Alejandro Orjuela-Guerrero

    2015-01-01

    Full Text Available Se produjeron recubrimientos de carburo de vanadio (VC sobre sustratos de acero AISI H13 y acero AISI D2 mediante deposito termoreactiva/ difusión (TRD con el fin de evaluar sus propiedades mecánicas como una función del contenido de vanadio. Los recubrimientos se producen con diferentes porcentajes de concentración de ferrovanadio. La composición química de los recubrimientos se determinó mediante fluorescencia de rayos X (XRF, la estructura cristalina se analizó utilizando difracción de rayos X (XRD, la morfología se caracterizó usando microscopía electrónica de barrido (SEM, la dureza se midió a través de nanoindentaciòn, y las propiedades tribológicas mediante la prueba de bola sobre disco. El análisis XRF indicó que los recubrimientos crecidos en acero D2 disminuyó el porcentaje atómico de vanadio cuando el recubrimiento se produce con 20% de ferrovanadio. El análisis XRD estableció que los recubrimientos eran policristalinos, con una estructura cúbica. Las imágenes de SEM revelaron que los recubrimientos crecidos en acero D2 eran más compactos que los crecidos en el acero H13. Finalmente, las pruebas de desgaste establecieron que el coeficiente de fricción disminuyó con un aumento de vanadio en el recubrimiento.

  14. Morbus Coats

    Science.gov (United States)

    Förl, B.; Schmack, I.; Grossniklaus, H.E.; Rohrschneider, K.

    2010-01-01

    Der fortgeschrittene Morbus Coats stellt im Kleinkindalter eine der schwierigsten Differenzialdiagnosen zum Retinoblastom dar. Wir beschreiben die klinischen und histologischen Befunde zweier Jungen im Alter von 9 und 21 Monaten mit einseitiger Leukokorie. Trotz umfassender Diagnostik mittels Narkoseuntersuchung, MRT und Ultraschall konnte ein Retinoblastom nicht sicher ausgeschlossen werden, und es erfolgte eine Enukleation. Histologisch wurde die Diagnose eines Morbus Coats gesichert. Da eine differenzialdiagnostische Abgrenzung zwischen Morbus Coats und Retinoblastom schwierig sein kann, halten wir in zweifelhaften Fällen auch angesichts der eingeschränkten Visusprognose und potenzieller Sekundärkomplikationen beim fortgeschrittenen Morbus Coats eine Enukleation für indiziert. PMID:18299842

  15. Absorptive coating for aluminum solar panels

    Science.gov (United States)

    Desmet, D.; Jason, A.; Parr, A.

    1979-01-01

    Method for coating forming coating of copper oxide from copper component of sheet aluminum/copper alloy provides strong durable solar heat collector panels. Copper oxide coating has solar absorption characteristics similar to black chrome and is much simpler and less costly to produce.

  16. Wear resistance of Fe-Nb-Cr-W, Nb, AISI 1020 and AISI 420 coatings produced by thermal spray wire arc; Resistencia al desgaste de recubrimientos Fe-Nb-Cr-W, Nb, AISI 1020 y AISI 420 producidos por proyeccion termica por arco electrico

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Covaleda, E. A.; Mercado-Veladia, J. L.; Olaya-Florez, J. J.

    2013-07-01

    The commercial materials 140MXC (with iron, tungsten, chrome, niobium), 530AS (AISI 1015 steel) and 560AS (AISI 420 steel) on AISI 4340 steel were deposited using thermal spray with arc. The aim of work was to evaluate the best strategy abrasive wear resistance of the system coating-substrate using the following combinations: (1) homogeneous coatings and (2) coatings depositing simultaneously 140MXC + 530AS and 140MXC + 560AS. The coatings microstructure was characterized using Optical microscopy, Scanning electron microscopy and Laser con focal microscopy. The wear resistance was evaluated through dry sand rubber wheel test (DSRW). We found that the wear resistance depends on the quantity of defects and the mechanical properties like hardness. For example, the softer coatings have the biggest wear rates and the failure mode was characterized by plastic deformation caused by particles indentation, and the other hand the failure mode at the harder materials was grooving. The details and wear mechanism of the coatings produced are described in this investigation. (Author)

  17. Direct Laser Synthesis of Functional Coatings

    Energy Technology Data Exchange (ETDEWEB)

    P. Schaaf; Michelle D. Shinn; E. Carpene; J. Kaspar

    2005-06-01

    The direct laser synthesis of functional coatings employs the irradiation of materials with short intensive laser pulses in a reactive atmosphere. The material is heated and plasma is ignited in the reactive atmosphere. This leads to an intensive interaction of the material with the reactive species and a coating is directly formed on the materials surface. By that functional coatings can be easily produced a fast way on steel, aluminium, and silicon by irradiation in nitrogen, methane, or even hydrogen. The influence of the processing parameters to the properties of the functional coatings will be presented for titanium nitride coating produced on titanium with the free electron laser.

  18. Nanocrystalline Ni-W coatings on copper

    Energy Technology Data Exchange (ETDEWEB)

    Panagopoulos, C.N., E-mail: chpanag@metal.ntua.gr [Laboratory of Physical Metallurgy, National Technical University of Athens, Zografos, 15780, Athens (Greece); Plainakis, G.D.; Lagaris, D.A. [Laboratory of Physical Metallurgy, National Technical University of Athens, Zografos, 15780, Athens (Greece)

    2011-04-15

    Nanocrystalline Ni-W coatings were produced on copper substrates with the aid of electrodeposition technique. The morphology, chemical composition and structure of the produced coatings were examined with the aid of scanning electron microscopy (SEM), electron dispersive spectroscopy (EDS) and X-ray diffraction (XRD) techniques. The microhardness of alloy Ni-W coatings on copper substrate was also studied. The adhesion between the Ni-W coating, having W content 50 wt%, and the copper substrate, was also studied with a scratch testing apparatus. The scratch tests resulted in the coatings suffering an intensive brittle fracture and minor delamination.

  19. Kinetic regulation of coated vesicle secretion

    CERN Document Server

    Foret, Lionel

    2008-01-01

    The secretion of vesicles for intracellular transport often rely on the aggregation of specialized membrane-bound proteins into a coat able to curve cell membranes. The nucleation and growth of a protein coat is a kinetic process that competes with the energy-consuming turnover of coat components between the membrane and the cytosol. We propose a generic kinetic description of coat assembly and the formation of coated vesicles, and discuss its implication to the dynamics of COP vesicles that traffic within the Golgi and with the Endoplasmic Reticulum. We show that stationary coats of fixed area emerge from the competition between coat growth and the recycling of coat components, in a fashion resembling the treadmilling of cytoskeletal filaments. We further show that the turnover of coat components allows for a highly sensitive switching mechanism between a quiescent and a vesicle producing membrane, upon a slowing down of the exchange kinetics. We claim that the existence of this switching behaviour, also tri...

  20. Efficient Utilization of Nickel Laterite to Produce Master Alloy

    Science.gov (United States)

    Ma, Xiaodong; Cui, Zhixiang; Zhao, Baojun

    2016-12-01

    To lower the smelting temperature associated with the carbothermic reduction processing of laterite, the optimization of slag and alloy systems was investigated to enable the reduction of laterite ore in the molten state at 1723 K. The master Fe-Ni-Mo alloy was successfully produced at a lower temperature (1723 K). The liquidus of the slag decreased with the addition of oxide flux (Fe2O3 and CaO) and that of the ferronickel alloy decreased with the addition of Mo/MoO3. More effective metal-slag separation was achieved at 1723 K, which reduces the smelting temperature by 100 K compared with the current electric furnace process. A small addition of Mo/MoO3 not only decreased the melting point of ferronickel alloys but also served as a collector to aggregate the ferronickel sponges allowing them to grow larger. The FeO concentration in the slag and the nickel grade of the alloy decreased with increasing graphite reductant addition.

  1. Bioceramics for implant coatings

    Directory of Open Access Journals (Sweden)

    Allison A Campbell

    2003-11-01

    Early research in this field focused on understanding the biomechanical properties of metal implants, but recent work has turned toward improving the biological properties of these devices. This has led to the introduction of calcium phosphate (CaP bioceramics as a bioactive interface between the bulk metal impart and the surrounding tissue. The first CaP coatings were produced via vapor phase processes, but more recently solution-based and biomimetic methods have emerged. While each approach has its own intrinsic materials and biological properties, in general CaP coatings promise to improve implant biocompatibility and ultimately implant longevity.

  2. Catalytic activities of Co(Ni)Mo/TiO{sub 2}-Al{sub 2}O{sub 3} catalysts in gasoil and thiophene HDS and pyridine HDN: effect of the TiO{sub 2}-Al{sub 2}O{sub 3} composition

    Energy Technology Data Exchange (ETDEWEB)

    Borque, M.P.; Lopez-Agudo, A. [Instituto de Catalisis y Petroleoquimica, CSIC, Cantoblanco, 28049 Madrid (Spain); Olguin, E.; Vrinat, M. [Institut de Recherches sur la Catalyse, 2 avenue Albert Einstein, 69626 Villeurbanne Cedex (France); Cedeno, L.; Ramirez, J. [Unicat, Facultad de Quimica UNAM, Cd. Universitaria, 04510 Mexico DF (Mexico)

    1999-04-19

    The effect of the TiO{sub 2}-Al{sub 2}O{sub 3} mixed oxide support composition on the hydrodesulfurization (HDS) of gasoil and the simultaneous HDS and hydrodenitrogenation (HDN) of gasoil+pyridine was studied over two series of CoMo and NiMo catalysts. The intrinsic activities for gasoil HDS and pyridine HDN were significantly increased by increasing the amount of TiO{sub 2} into the support, and particularly over rich- and pure-TiO{sub 2}-based catalysts. It is suggested that the increase in activity be due to an improvement in reducing and sulfiding of molybdena over TiO{sub 2}. The inhibiting effect of pyridine on gasoil HDS was found to be similar for all the catalysts, i.e., was independent of the support composition. The ranking of the catalysts for the gasoil HDS test differed from that obtained for the thiophene test at different hydrogen pressures. In the case of gasoil HDS, the activity increases with TiO{sub 2} content and large differences are observed between the catalysts supported on pure Al{sub 2}O{sub 3} and pure TiO{sub 2}. In contrast, in the case of the thiophene test, the pure Al{sub 2}O{sub 3}-based catalyst appeared relatively more active than the catalysts supported on mixed oxides. Also, in the thiophene test the difference in intrinsic activity between the pure Al{sub 2}O{sub 3}-based catalyst appeared relatively more active than the catalysts supported on mixed oxides. Also in the thiophene test, the difference in intrinsic activity between the pure Al{sub 2}O{sub 3}- and pure TiO{sub 2}-based catalysts is relatively small and dependent on the H{sub 2} pressure used. Such differences in activity trend among the gasoil and the thiophene tests are due to a different sensitivity of the catalysts (by different support or promoter) to the experimental conditions used. The results of the effect of the H{sub 2} partial pressure on the thiophene HDS, and on the effect of H{sub 2}S concentration on gasoil HDS demonstrate the importance of these

  3. Kinetic model of induced codeposition of Ni-Mo alloys

    Institute of Scientific and Technical Information of China (English)

    ZENG, Yue; MA, Ming; XIAO, Xiao-Ming; LI, Ze-Lin; LIAN, Shi-Xun; ZHOU, Shao-Min

    2000-01-01

    The kinetic model of induced codeposition of nickel-molybdenum alloys from ammoniun citrate solution was studied on rotating disk electrodes to predict the behavior of the electrodeposition. Ihe molybdate (MoO42-) could be firstly electrochemically reduced to MoO2, and subsequently undergoes a chemical reduction with atomic hydrogen previously adsorbed on the inducing metal nickel to form molybdenum in alloys.The kinetic equations were derived, and the kinetic parameters were obtained from a comparison of experimental results and the kinetic equations. The electrochemical rate constants for discharge of nickel, molybdenum and water could been expressed as k1 ( E ) = 1. 23 × 10-9 CNexp( - 0. 198FE/ RT )mol/(dm2. s), k2 (E) = 3.28 × 10-10 CMoexp ( - 0.208FE/RT) mol/(dm2·s) and k3(E) = 1.27 × 10-6exp( - 0.062FE/RT) mol/(dm2 ·s), where CN and CMo are the concentrations of the nickel ion and molybdate, respectively, and E is the applied potential vs, saturated calornel electrode (SCE).The codeposition process could be well simulated by this model.

  4. Controlled reactions between chromia and coating on alloy surface

    DEFF Research Database (Denmark)

    Linderoth, Søren

    1996-01-01

    An electrically conducting Sr-doped lanthanum chromite (LSC) coating has been produced by reacting a coating of fine particles of La oxide and Sr oxide with chromia formed as an external scale on a metallic alloy. In addition to the formation of LSC the coating also resulted in much reduced...... buckling of the underlying chromia layer compared with a non-coated alloy....

  5. Transparent nanocrystalline diamond coatings and devices

    Energy Technology Data Exchange (ETDEWEB)

    Sumant, Anirudha V.; Khan, Adam

    2017-08-22

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

  6. Producing superhydrophobic roof tiles

    Science.gov (United States)

    Carrascosa, Luis A. M.; Facio, Dario S.; Mosquera, Maria J.

    2016-03-01

    Superhydrophobic materials can find promising applications in the field of building. However, their application has been very limited because the synthesis routes involve tedious processes, preventing large-scale application. A second drawback is related to their short-term life under outdoor conditions. A simple and low-cost synthesis route for producing superhydrophobic surfaces on building materials is developed and their effectiveness and their durability on clay roof tiles are evaluated. Specifically, an organic-inorganic hybrid gel containing silica nanoparticles is produced. The nanoparticles create a densely packed coating on the roof tile surface in which air is trapped. This roughness produces a Cassie-Baxter regime, promoting superhydrophobicity. A surfactant, n-octylamine, was also added to the starting sol to catalyze the sol-gel process and to coarsen the pore structure of the gel network, preventing cracking. The application of ultrasound obviates the need to use volatile organic compounds in the synthesis, thereby making a ‘green’ product. It was also demonstrated that a co-condensation process effective between the organic and inorganic species is crucial to obtain durable and effective coatings. After an aging test, high hydrophobicity was maintained and water absorption was completely prevented for the roof tile samples under study. However, a transition from a Cassie-Baxter to a Wenzel state regime was observed as a consequence of the increase in the distance between the roughness pitches produced by the aging of the coating.

  7. The development of a nanostructured, graded multilayer Cr-CrxNy-Cr1-xAlxN coating produced by pulsed closed field unbalanced magnetron sputtering (P-CFUBMS) for use in aluminum pressure die casting dies.

    Science.gov (United States)

    Lin, Jianliang; Mishra, Brajendra; Myers, Sterling; Ried, Peter; Moore, John J

    2009-06-01

    The main objective of this research is to design an optimized 'coating system' that extends die life by minimizing premature die failure. The concept of the multilayer coating system with desired combinations of different kinds of single-layer coatings was introduced. A pulsed closed field unbalanced magnetron sputtering (P-CFUBMS) deposition system has been used to deposit Cr-CrxNy-Cr1-xAlxN compositionally graded multilayer coating structures. In this study, three power law scenarios have been adopted to vary the aluminum concentration in the graded Cr1-xAlxN layer: (i) p = 1, the aluminum concentration was increased linearly in the Cr1-xAlxN layer. (ii) p = 0.2, the Cr1-xAlxN layer is an aluminum-rich graded layer, and (iii) p = 2, the Cr1-xAlxN layer is a chromium-rich graded layer. It was found that all the graded coatings exhibit lower residual stress and higher adhesion strength than the homogeneous Cr1-xAlxN (x = 0.585) film. However, different power law grading architectures have significant influence on the hardness and wear resistance of the films. When p = 2 and p = 1, the graded films exhibited relatively low hardness values (24 and 26 GPa respectively) and high COF (0.55 to 0.60). When p = 0.2 the graded film exhibited both high hardness (34 GPa) and good wear resistance (COF = 0.45) due to the structural consistency in the graded zone. The paper discusses the correlation between the pulsing parameters and coating architecture with the resulting nanostructure and tribological properties of this Cr-CrxNy-Cr1-xAlxN coating system.

  8. Pack cementation coatings for alloys

    Energy Technology Data Exchange (ETDEWEB)

    He, Yi-Rong; Zheng, Minhui; Rapp, R.A. [Ohio State Univ., Columbus, OH (United States)

    1996-08-01

    The halide-activated pack cementation process was modified to produce a Ge-doped silicide diffusion coating on a Cr-Cr{sub 2}Nb alloy in a single processing step. The morphology and composition of the coating depended both on the composition of the pack and on the composition and microstructure of the substrate. Higher Ge content in the pack suppressed the formation of CrSi{sub 2} and reduced the growth kinetics of the coating. Ge was not homogeneously distributed in the coatings. In cyclic and isothermal oxidation in air at 700 and 1050{degrees}C, the Ge-doped silicide coating protected the Cr-Nb alloys from significant oxidation by the formation of a Ge-doped silica film. The codeposition and diffusion of aluminum and chromium into low alloy steel have been achieved using elemental Al and Cr powders and a two-step pack cementation process. Sequential process treatments at 925{degrees}C and 1150{degrees}C yield dense and uniform ferrite coatings, whose compositions are close to either Fe{sub 3}Al or else FeAl plus a lower Cr content, when processed under different conditions. The higher content of Al in the coatings was predicted by thermodynamic calculations of equilibrium in the gas phase. The effect of the particle size of the metal powders on the surface composition of the coating has been studied for various combinations of Al and Cr powders.

  9. Protective Coatings

    Science.gov (United States)

    1980-01-01

    General Magnaplate Corporation's pharmaceutical machine is used in the industry for high speed pressing of pills and capsules. Machine is automatic system for molding glycerine suppositories. These machines are typical of many types of drug production and packaging equipment whose metal parts are treated with space spinoff coatings that promote general machine efficiency and contribute to compliance with stringent federal sanitation codes for pharmaceutical manufacture. Collectively known as "synergistic" coatings, these dry lubricants are bonded to a variety of metals to form an extremely hard slippery surface with long lasting self lubrication. The coatings offer multiple advantages; they cannot chip, peel or be rubbed off. They protect machine parts from corrosion and wear longer, lowering maintenance cost and reduce undesired heat caused by power-robbing friction.

  10. Structure and corrosion properties of PVD Cr-N coatings

    CERN Document Server

    Liu, C; Ziegele, H; Leyland, A; Matthews, A

    2002-01-01

    PVD Cr-N coatings produced by physical vapor deposition (PVD) are increasingly used for mechanical and tribological applications in various industrial sectors. These coatings are particularly attractive for their excellent corrosion resistance, which further enhances the lifetime and service quality of coated components. PVD Cr-N coated steels in an aqueous solution are usually corroded by galvanic attack via through-coating 'permeable' defects (e.g., pores). Therefore, the corrosion performance of Cr-N coated steel is determined by a number of variables of the coating properties and corrosive environment. These variables include: (i) surface continuity and uniformity; (ii) through-coating porosity; (iii) film density and chemical stability; (iv) growth stresses; (v) interfacial and intermediate layers; (vi) coating thickness; (vii) coating composition; and (viii) substrate properties. In this article, PVD Cr-N coatings were prepared, by electron-beam PVD and sputter deposition, with different compositions, t...

  11. for zeolite coating

    Directory of Open Access Journals (Sweden)

    Carlos Renato Rambo

    2006-01-01

    Full Text Available Biotemplating is the processing of microcellular ceramics by reproduction of natural morphologies, where the microstructural features of the biotemplate are maintained in the biomorphic ceramic. Different biotemplates with distinct pore anatomies were used to produce biomorphic supports for the zeolite coating: wood, cardboard, sea-sponge and sisal. The biomorphic ceramics were produced by distinguished processing routes: Al-gas infiltration-reaction, liquid-metal infiltration, dip-coating and sol-gel synthesis, in order to produce nitrides, carbides and oxides, depending on the processing conditions. The zeolite coating was performed by hydrothermal growth of MFI-type (Silicalite-1 and ZSM-5 zeolite crystals onto the internal pore walls of the biomorphic templates. The final biomorphic ceramic-zeolite composites were physically characterized, evaluated in terms of their gas adsorption capabilities and correlated to their microstructure and specific pore anatomy. The combination of the properties of the biomorphic ceramics with the adsorption properties of zeolites results in materials with distinct properties as potential candidates for adsorption and catalytic applications due to their characteristic porosity, molecular sieving capabilities and high thermo-mechanical strength.

  12. Performance of chromium nitride based coatings under plastic processing conditions

    OpenAIRE

    Cunha, l.; Andritschky, M.; Pischow, K.; Wang, Z.(Institute of High Energy Physics, Beijing, China); Zarychta, A.; Miranda, A. S.; A.M. Cunha

    2000-01-01

    Chromium nitride based coatings were produced in the form of monolithic and multilayer coatings, by DC and RF reactive magnetron sputtering. These coatings were deposited onto stainless steel and tool steel substrates. Chromium nitride coatings have;proved to be wear and corrosion resistant. The combination of these characteristics was necessary to protect surfaces during plastic processing. In order to select the best coatings, some mechanical and tribological tests were performed. Har...

  13. Graphene Coatings

    DEFF Research Database (Denmark)

    Stoot, Adam Carsten; Camilli, Luca; Bøggild, Peter

    2014-01-01

    Owing to its remarkable electrical and mechanical properties, graphene has been attracting tremendous interest in materials science. In particular, its chemical stability and impermeability make it a promising protective membrane. However, recent investigations reveal that single layer graphene...... cannot be used as a barrier in the long run, due to galvanic corrosion phenomena arising when oxygen or water penetrate through graphene cracks or domain boundaries. Here, we overcome this issue by using a multilayered (ML) graphene coating. Our lab- as well as industrial-scale tests demonstrate that ML...... that graphene can still be a relevant candidate for thin coatings....

  14. A Review on Origin of Ni-Mo Polymetallic Deposits in Lower Cambrian Black Rock Series in South China%华南早寒武世黑色岩系Ni-Mo多金属矿床成因研究进展

    Institute of Scientific and Technical Information of China (English)

    施春华; 曹剑; 胡凯; 韩善楚; 边立曾; 姚素平

    2011-01-01

    通过调研分析我国华南早寒武世黑色岩系Ni-Mo多金属矿床成因研究的现状,述评了这一领域的研究进展,提出了今后深化研究值得加强的方向.将已有提出的矿床成因模式总体归纳为5种观点:陨石撞击同沉积、岩浆火山碎屑、海水、热水、多源,并且认为目前主要侧重于对热水和海水两种成因的研究,这两方面积累的证据较多,争议也较大.结合生物有机质在矿床形成过程中起到了重要作用,即生物有机成矿作用,认为矿床成因复杂,受到热水、海水、生物有机质的多元复合作用.总体而言,各种矿床成因观点均各有l证据支持,但因成矿过程复杂,成矿地质作用多样,所以尚不能够完全全面、合理地揭示成矿过程,仍有待进一步深入工作;建议加强原位实验分析测试技术的应用和矿床成因研究的时空对比.这些认识为存在诸多争议和不确定性的该领域研究提供了参考,并且因这一分析寸象是全球黑色岩系矿床的一个典型实例,所以认识可望具有普遍参考意义.%The origin of Ni-Mo polymetallic deposits hosted in Lower Cambrian black rock series in South China was reviewed in this paper. Future research directions were further suggested based on the review. In general, the origin can be summarized and divided into five perspectives, including meteoritic impact syndeposition, magma volcanic collapse, sea water, hydrothermal water, and multiple sources. The present works are focused mainly on the sea water and hydrothermal water origins. They have relatively large amount of evidence. However, the issue still has disputes. In addition, bioorganisms and organic matters have important impacts on the formation of the deposits. This is so-called bio-organic mineralization. Thus, we propose that the formation of the deposits has complex mineralization processes, including sea water, hydrothermal water and organic matters. Each of these

  15. Oxidation Resistance of CVD (Chemical Vapor Deposition) Coatings

    Science.gov (United States)

    1987-02-01

    carbonaceous residuoe were overcome, and dense, iadherent, coat-ings which :ýtop oxidat-ion Of the substrate art! reliably produced. The iridium deposition...flow, pressure and geometry within the reaction chamber, and substrate material. For the coating to have high integrity and adhesion to the substrate...entirely produced by Ultramet using chemical vapor deposition and a novel integrated fabrication technique. Coating the inside of a long chamber presents

  16. Methods and apparatus for coating particulate material

    Science.gov (United States)

    Littman, Howard (Inventor); Plawsky, Joel L. (Inventor); Paccione, John D. (Inventor)

    2012-01-01

    Methods and apparatus for coating particulate material are provided. The apparatus includes a vessel having a top and a bottom, a vertically extending conduit having an inlet in the vessel and an outlet outside of the vessel, a first fluid inlet in the bottom of the vessel for introducing a transfer fluid, a second fluid inlet in the bottom of the vessel for introducing a coating fluid, and a fluid outlet from the vessel. The method includes steps of agitating a material, contacting the material with a coating material, and drying the coating material to produce a coated material. The invention may be adapted to coat aerogel beads, among other materials. A coated aerogel bead and an aerogel-based insulation material are also disclosed.

  17. Properties of Plasma and HVOF Sprayed Coatings

    Directory of Open Access Journals (Sweden)

    Wojciech Żórawski

    2012-11-01

    Full Text Available The work compares the properties of plasma and HVOF thermally sprayed coatings obtained by blending the NiCrBSi and Fe2O3 powders. The deposition was performed by means of the Plancer PN-120 and the Diamond Jet guns for plasma spraying and HVOF spraying respectively. The SEM (EDS method was employed to study the microstructure of the produced coatings. Although the blended powders differ in particle size, shape, and distribution, it is possible to obtain composite coatings with an NiCrBSi matrix containing iron oxides. Except for a different microstructure, plasma and HVOF coatings have a different phase composition, which was examined using the Bruker D-8 Advance diffractometer. Studies of the coatings wear and scuffing resistance showed that an optimal content of Fe2O3 is about 26 % for plasma sprayed coatings and 22.5 % for HVOF deposited coatings.

  18. Laser cladding of bioactive glass coatings.

    Science.gov (United States)

    Comesaña, R; Quintero, F; Lusquiños, F; Pascual, M J; Boutinguiza, M; Durán, A; Pou, J

    2010-03-01

    Laser cladding by powder injection has been used to produce bioactive glass coatings on titanium alloy (Ti6Al4V) substrates. Bioactive glass compositions alternative to 45S5 Bioglass were demonstrated to exhibit a gradual wetting angle-temperature evolution and therefore a more homogeneous deposition of the coating over the substrate was achieved. Among the different compositions studied, the S520 bioactive glass showed smoother wetting angle-temperature behavior and was successfully used as precursor material to produce bioactive coatings. Coatings processed using a Nd:YAG laser presented calcium silicate crystallization at the surface, with a uniform composition along the coating cross-section, and no significant dilution of the titanium alloy was observed. These coatings maintain similar bioactivity to that of the precursor material as demonstrated by immersion in simulated body fluid. Copyright 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  19. Coating of silicon pore optics

    DEFF Research Database (Denmark)

    Cooper-Jensen, Carsten P.; Ackermann, M.; Christensen, Finn Erland

    2009-01-01

    For the International X-ray observatory (IXO), a mirror module with an effective area of 3 m2 at 1.25 keV and at least 0.65 m2 at 6 keV has to be realized. To achieve this goal, coated silicon pore optics has been developed over the last years. One of the challenges is to coat the Si plates...... and still to realize Si-Si bonding. It has been demonstrated that ribbed silicon plates can be produced and assembled into stacks. All previously work has been done using uncoated Si plates. In this paper we describe how to coat the ribbed Si plates with an Ir coating and a top C coating through a mask so...... that there will be coating only between the ribs and not in the area where bonding takes place. The paper includes description of the mounting jig and how to align the mask on top of the plate. We will also present energy scans from Si plates coated through a mask....

  20. Resistencia al desgaste de recubrimientos de bronce al aluminio producidos con técnica de proyección térmica//Wear resistance of aluminum bronze coatings produced by thermal spray

    Directory of Open Access Journals (Sweden)

    Dayan Carolina Cárdenas-Feria

    2015-09-01

    Full Text Available Se estudió la resistencia al desgaste adhesivo de recubrimientos de bronce al aluminio depositados con la técnica de proyección térmica por llama sobre bronce fosforado SAE 62. Los recubrimientos fueron fabricados variando las presiones parciales de los gases de combustión, oxígeno y acetileno. El material utilizado fue caracterizado estructuralmente mediante difracción de rayosX (X-ray diffraction, XRD y el estudio morfológico mediante microscopía electrónica de barrido (Scanning electron microscopy, SEM. La resistencia al desgaste adhesivo de los recubrimientos se determinó por medio del ensayo de bola sobre disco, utilizando como bola una esférica de acero 100Cr6. Los resultados obtenidos permiten establecer que los recubrimientos proyectados con una presión de oxigeno de 78 psi y una presión de acetileno de 8 psi presentan la mejor resistencia al desgaste en comparación a los tratamientos producidos. El modo de falla de desgaste en los recubrimientos producidos es discutido en esta investigación.Palabras clave: desgaste abrasivo y adhesivo,  proyección térmica,  recubrimientos.______________________________________________________________________________AbstractWe studied the adhesive wear resistance of aluminum bronze coatings deposited by thermal spray on phosphor bronze SAE 62 substrates. The coatings were deposited by varying the partial pressures of the combustion gases: oxygen and acetylene. The structural characterization was made through X-ray diffraction (XRD and the morphological analysis was performed by scanning electron microscopy (SEM. The adhesive wear resistance of the coatings was determined by the bole on disc test using a spherical ball made of steel 100Cr6 and with a diameter of 6 mm. The results obtained show that the coating projected with an oxygen pressure of 78 psi and an acetylene pressure of 8 psi have the better wear resistance compared with the substrate and the others treatments deposited

  1. Tough ceramic coatings: Carbon nanotube reinforced silica sol-gel

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, A.J., E-mail: antoniojulio.lopez@urjc.es [Dept. de Ciencia e Ingenieria de Materiales, ESCET, Universidad Rey Juan Carlos, C/Tulipan s/n, Mostoles 28933, Madrid (Spain); Rico, A.; Rodriguez, J.; Rams, J. [Dept. de Ciencia e Ingenieria de Materiales, ESCET, Universidad Rey Juan Carlos, C/Tulipan s/n, Mostoles 28933, Madrid (Spain)

    2010-08-15

    Silica coatings reinforced with carbon nanotubes were produced via sol-gel route using two mixing techniques of the sol-gel precursors, mechanical and ultrasonic mixing, and dip-coating as deposition process on magnesium alloy substrates. Effective incorporation and distribution of 0.1 wt.% of carbon nanotubes in the amorphous silica matrix of the coatings were achieved using both techniques. Fabrication procedure determines the morphological aspects of the coating. Only mechanical mixing process produced coatings dense and free of defects. Nanoindentation technique was used to examine the influence of the fabrication process in the mechanical features of the final coatings, i.e. indentation fracture toughness, Young's modulus and hardness. A maximum toughening effect of about 24% was achieved in silica coatings reinforced with carbon nanotubes produced by the mechanical mixing route. Scanning electron microscopy investigation revealed that the toughening of these reinforced coatings was mainly due to bridging effect of the reinforcement.

  2. Bioactivity of Gradient Rare Earths Bioceramic Coating Produced by Wide-Band Laser Cladding%宽带激光熔覆梯度稀土生物陶瓷涂层的生物活性

    Institute of Scientific and Technical Information of China (English)

    李明; 汪震

    2012-01-01

    To decrease thermal crack and to raise bonding strength between substrate and bioceramic coating during laser cladding, a kind of gradient rare earths bioceramics coating is designed. And the rare earth active gradient bioceramic coating with HA and β-TCP on Ti allloy was prepared by using wide-band laser cladding technique. The surface morphologies and microstructure were analyzed by OM, SEM and XRD; the bioceramic coating was immersed in SBF to examine its bioactivity ; and the corrosion resistance of bioceramic was examed by the Electrochemical Analyzer. Results show that the rare earth active bioceramic gradient coatings which have excellent chemical metallurgy bonding at the interface consists of substrate, alloying layer and bioceramic coating. When content of Nd2O3 is up to 0.6wt.%, the amount of HA+β — TCP catalyzed during wide-band laser cladding becomes largest. Bioactivity and corrosion resistance of bioceramic coating is dependent on the amount of HA + β—TCP catalyzed. The largest amount of apatite formed on the surface of gradient bioceramic coating is complied with 0.6wt.% Nd2O3. At the same time, the corrosion resistence is best.%为了减少激光熔覆过程中基材与生物陶瓷涂层之间的热裂纹,提高涂层与基材的结合强度,设计了一种梯度稀土生物陶瓷涂层,采用宽带激光熔覆技术,在TC4钛合金表面制备了含HA+β-TCP活性相的稀土活性梯度生物陶瓷复合涂层.利用SEM、XRD分析手段对涂层形貌、相组成进行了研究;通过模拟体液(SBF)浸泡实验(浸泡7、14 d)考察了生物陶瓷涂层的生物活性;利用电化学分析仪测试了生物活性陶瓷涂层的耐腐蚀性.结果表明,当稀土氧化物Nd2O3添加量为w(Nd2O3) =0.6%时,宽带激光熔覆过程中催化合成HA +3-TCP活性相的数量最多,具有优异的表面形貌;当稀土氧化物Nd2O3添加量为w(Nd2O3)=0.6%时,梯度稀土生物陶瓷涂层在SBF中浸泡不同时间点后表面沉

  3. Y2O3对等离子喷焊高铬铁基涂层组织和性能的影响%Effect of Y2O3on microstructure and properties of high-chromium Fe-base coating produced by plasma arc cladding process

    Institute of Scientific and Technical Information of China (English)

    李殿凯; 李明喜; 洪海峰

    2013-01-01

    采用光学显微镜、扫描电镜(SEM)、X射线衍射(XRD)以及磨损实验,研究了添加1%(质量分数)Y2O3对等离子喷焊高铬铸铁型铁基合金涂层组织和耐磨性的影响.结果表明,加入1%Y2O3并未改变涂层中相的组成,主要都是由面心立方的γ(Fe、Ni)固溶体和六方结构的M7C3型碳化物构成,但使γ(Fe、Ni)固溶体生长晶面由[002]转变为以[111]和[002]晶面为主.由于涂层中Y2O3的加入,稀土氧化物颗粒可作为异质形核核心,细化组织,并抑制碳化物的生长,使其弥散分布于共晶组织中,从而提高喷焊层的显微硬度和耐磨性能.%High chromium iron based coatings with and without 1% Y2O3 were produced by plasma arc cladding process on a low carbon steel.Microstructure and tribological characteristics of the coatings were studied using optical microscope,scanning electron microscopy,X-ray diffraction and wear test.The results show that the high chromium iron based coating is composed of γ-(FeNi) solid solution with face-centered cubic lattice and M7 C3 (M =Cr,Fe,Mo) carbides with hexagonal lattice structure.The Y2O3 in the Fe-based coating doesn't change the coating' s phase composition,but it changes the crystal growth direction of γ-(Fe,N i)solid solution from almost single[002]to both [111] and [002].The rare earth oxide Y2O3 not only acts as the heterogeneous nucleation to refine the microstructure but also restrains the growth of the carbides.Additionally,it improves the microhardness and wear resistance of the coating by making the refined carbide particles dispersively distribute in the coating matrix.

  4. Method for fluidizing and coating ultrafine particles, device for fluidizing and coating ultrafine particles

    Science.gov (United States)

    Li, Jie; Liu, Yung Y

    2015-01-20

    The invention provides a method for dispersing particles within a reaction field, the method comprising confining the particles to the reaction field using a standing wave. The invention also provides a system for coating particles, the system comprising a reaction zone; a means for producing fluidized particles within the reaction zone; a fluid to produce a standing wave within the reaction zone; and a means for introducing coating moieties to the reaction zone. The invention also provides a method for coating particles, the method comprising fluidizing the particles, subjecting the particles to a standing wave; and contacting the subjected particles with a coating moiety.

  5. Erosion Behavior of Fe3Al/WC Intermetallic Matrix Composite Coating Produced By High Velocity Arc spray at Elevated Temperature%高速电弧喷涂Fe3Al/WC复合涂层高温冲蚀行为研究

    Institute of Scientific and Technical Information of China (English)

    田保红; 徐滨士; 马世宁; 胡军志; 张伟

    2000-01-01

    A novel cored wire for producing Fe3Al/WC intermetallic matrix composite (IMC) coating by thermal spraying was developed. High velocity arc wire spray technology was successfully applied to prepare the Fe3Al/WC IMC coating. The coating composition, microstructure and phases were investigated by energy dispersive X-ray (EDX), X-ray diffraction (XRD), scanning electron microscope (SEM) and image analyzer. Results show that the cored wire arc sprayed iron aluminide IMC coating consists of major phases of Fe3Al (Fe-26Al) and the reinforced hard phases of about 20%WC,W2C and a -Al2O3. As compared with boiler tube steel, the solid particles erosion-corrosion behavior under different incidence angles and test temperatures of Fe3Al/WC IMC coatings were determined. Results indicate that the erosion-corrosion resistance at elevated temperature of Fe3Al/WC IMC coating is higher than that of 20g steel. Under oblique impact condition, the relative erosion-corrosion resistance of Fe3Al is 3.14 times than that of 20g steel at temperature of 650℃. It seems that test temperature has great effect on the solid particle erosion behavior of Fe3Al/WC IMC coating. It is found that the Fe3Al/WC coating exhibits typical erosion behavior of ductile materials as increasing test temperature prior to 450℃. With increasing temperature beyond 450℃,the Fe3Al/WC IMC coating turns to exhibit the erosion behavior of brittle material. The erosion-corrosion mechanisms of Fe3Al/WC IMC coatings under elevated temperature were discussed.%采用自行研制的新型热喷涂Fe3Al/WC复合合金粉芯丝材,成功地用高速电弧喷技术制备出了Fe3Al金属化合物基金属陶瓷复合涂层。对涂层成分、显微组织、涂层相结构和组成进行了分析,结果表明,涂层由以Fe 26Al为主的Fe3Al基体相与约20%的WC、W2C和 a Al2O3相组成。对比研究了Fe3Al/WC涂层和电站锅炉钢20 g从室温至650 ℃氧化环境条件下不同攻角的高温冲蚀

  6. Stresses and Cracks in Surface Coatings

    DEFF Research Database (Denmark)

    Horsewell, Andy

    2000-01-01

    This extended abstract of the talk to be given at the Danish Metallurgical Society, Winter Meeting 1999, gives an outline of the areas of interest in current projects in wear and corrosion resistant coatings at Materials Technology, Technical University of Denmark (IPT, Materialeteknologi, DTU......). It also briefly describes our method of approach in analysing new coating / substrate combinations or new materials processing techniques for producing a given coating. We strive to combine, often in collaboration with others, a fundamental understanding of microstructure, mechanical properties...... and fracture mechanics in order to determine the mechanical stability of engineering coatings for various critical applications....

  7. Characterization of novel silane coatings on titanium implant surfaces

    NARCIS (Netherlands)

    Matinlinna, Jukka P; Tsoi, James Kit‐Hon; de Vries, Jacob; Busscher, Hendrik

    2013-01-01

    Objectives This in vitro study describes and characterizes a developed novel method to produce coatings on Ti. Hydrophobic coatings on substrates are needed in prosthetic dentistry to promote durable adhesion between luting resin cements and coated Ti surfaces. In implant dentistry the hydrophobic c

  8. Protection of aluminium by duplex coatings

    Energy Technology Data Exchange (ETDEWEB)

    Musil, J. [Ceska Akademie Ved, Prague (Czech Republic). Fyzikalni Ustav; Vlcek, J. [West Bohemia Univ., Plzen (Czech Republic). Dept. of Phys.; Jezek, V. [West Bohemia Univ., Plzen (Czech Republic). Dept. of Phys.; Benda, M. [West Bohemia Univ., Plzen (Czech Republic). Dept. of Phys.

    1995-11-01

    The paper reports on a new way of producing duplex coatings consisting of two steps. First, the substrate is coated by a physically vapour-deposited coating. Then, this precoated substrate is plasma nitrided or vacuum heat treated. This method was tested in the protection of substrates made of aluminium with a sputtered Ti coating about 5 {mu}m thick. The as-deposited and then plasma-nitrided or vacuum-heat-treated (Ti coating)/(Al substrate) couple was characterized by elemental depth profiles measured by glow discharge optical spectroscopy. It was shown that both the plasma nitriding and vacuum heat treatment process can stimulate a strong interdiffusion between Ti and the substrate elements. It results not only in the formation of a very broad interfacial region with a dramatic redistribution of the substrate elements in the Ti film but also in a formation of intermetallic Ti-Al compounds. This new duplex coating technique is described in detail. (orig.)

  9. Coating Characters and Interface Behavior between TA2 and Zr/WC Coating Produced by Electro-spark Deposition%TA2表面电火花沉积Zr/WC复合涂层特性及界面行为研究

    Institute of Scientific and Technical Information of China (English)

    吴公一; 张占领; 孙凯伟; 于华; 邱然锋; 石红信; 张柯柯

    2016-01-01

    Objective To study the Zr/WC coating character and behavior on the surface of TA2 by electro-spark deposition.Methods The microstructure, the chemical composition distribution, the residual stress, the micro-hardness distribution and the relative wear resistance were received by canning electron micro-scopy ( SEM) , energy dispersion spectrum ( EDX) , X-ray stress analyser, hardness meter and wear tester. Results The deposited layer was continuous and uniform. The thickness was about 50μm to 80 μm, the coating surface was not flat, there were a lot of small pits and adhesion. The coating section had a small amount of porosity and crack. Mutual diffusion of main elements happened between coating surface and substrate. The obtained coating was a composite coating by metallurgical reaction between Ti, Zr, and WC. Residual stresses existed in the coating and the residual stress of the property can be controlled by changing the technological parameters. The micro-hardness of the coating surface was about 4 times as that of the substrate, the wear quality of Zr/WC composite coating was much less than that of TA2,εw=4. 1, the relative wear resistance of the deposited layer was increased by 3. 1 times, the wear resistance improved significantly. Conclusion The performance of the substrate can be improved by TA2 and Zr/WC coating.%目的 通过在TA2表面进行电火花沉积改变其表面性能. 方法 采用电火花沉积技术,在基体TA2表面制备Zr/WC复合涂层,然后分别用扫描电镜( SEM)、能谱分析仪( EDX)、X射线应力分析仪、显微硬度计和摩擦磨损试验机分析涂层的微观组织、化学成分分布、残余应力、显微硬度分布以及涂层的耐磨性. 结果 复合涂层连续、均匀,厚度约为50~80 μm;涂层表面不平整,存在很多小坑和粘连,涂层内部有少量气孔和裂纹;复合涂层与基体的主要元素Ti、Zr、W之间发生相互扩散,并发生冶金反应;经过电火花沉积后TA2表面

  10. Brush seal shaft wear resistant coatings

    Science.gov (United States)

    Howe, Harold

    1995-03-01

    Brush seals suffer from high wear, which reduces their effectiveness. This work sought to reduce brush seal wear by identifying and testing several industry standard coatings. One of the coatings was developed for this work. It was a co-sprayed PSZ with boron-nitride added for a high temperature dry lubricant. Other coatings tested were a PSZ, chrome carbide and a bare rotor. Testing of these coatings included thermal shocking, tensile testing and wear/coefficient of friction testing. Wear testing consisted of applying a coating to a rotor and then running a sample tuft of SiC ceramic fiber against the coating. Surface speeds at point of contact were slightly over 1000 ft/sec. Rotor wear was noted, as well as coefficient of friction data. Results from the testing indicates that the oxide ceramic coatings cannot withstand the given set of conditions. Carbide coatings will not work because of the need for a metallic binder, which oxidizes in the high heat produced by friction. All work indicated a need for a coating that has a lubricant contained within itself and the coating must be resistant to an oxidizing environment.

  11. Incorporation of proteins into biomimetic hydroxyapatite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Y.; Groot, K. de [Leiden Univ. (Netherlands). Biomaterials Research Group; IsoTis, Bilthoven (Netherlands); Layrolle, P. [IsoTis, Bilthoven (Netherlands); Blitterswijk, C.A. van [IsoTis, Bilthoven (Netherlands); Twente Univ., Enschede (Netherlands)

    2001-07-01

    Hydroxyapatite coating was biomimetically deposited on titanium alloy (Ti6Al4V). Various concentrations (10 ng/ml - 1 {mu}g/ml) of bovine serum albumin (BSA) were added into a supersaturated calcium phosphate solution (CPS) at physiological temperature and pH of 7.4. Pre-treated Ti6Al4V plates were immersed into such solution for 48 hours at 37 C. BSA was co-precipitated with the crystals during the coating process. A white and thick (30 - 50 {mu}m) coating was uniformly deposited on titanium surfaces. The produced coatings were evaluated and protein release was measured. Results revealed: at higher BSA concentrations in the solution, the coating changed its microstructure; the crystal size of the coating and the coating thickness decreased indicating a crystal growth inhibition. Loading amounts of protein in the coating increased with higher concentration in the solution. Protein was incorporated into whole layer of coating and lead to a slow release. These results indicated that biomimetic hydroxyapatite coatings are suitable carriers for proteins. (orig.)

  12. Recobrimentos de poli (tereftalato de etileno depositados em aço por aspersão térmica a partir de pós obtidos em diferentes condições de moagem Thermally sprayed coated carbon steel produced using PET powder obtained in different grinding conditions

    Directory of Open Access Journals (Sweden)

    Luciana Tavares Duarte

    2003-07-01

    Full Text Available Neste trabalho foram analisados recobrimentos de poli(tereftalato de etileno, PET, depositados em aço carbono através da técnica de aspersão térmica à combustão, e produzidos a partir de pós oriundos de processos de moagem, em moinho de bolas e de facas, de garrafas de PET pós-consumo. Algumas condições de moagem foram testadas, tendo-se obtido pós com diferentes características morfológicas. As características morfológicas dos pós e dos recobrimentos foram avaliadas por microscopia óptica e eletrônica, tendo-se observado que o recobrimento apresentava bolhas, provavelmente devido à degradação do polímero. Além disto, os recobrimentos produzidos, bem como as amostras de pó, foram caracterizados por espectroscopia na região do infravermelho, por calorimetria exploratória diferencial e através da determinação de viscosidade intrínseca em solução. Os resultados obtidos mostraram que é possível a produção de aço carbono recoberto com PET através da técnica de aspersão térmica, sendo que o grau de degradação, a morfologia e a distribuição granulométrica dos pós utilizados influenciaram significativamente as características e propriedades dos recobrimentos formados.The main purpose of this work was to study the production of a thermal spray coated poly(ethyleneterephthalate steel. Poly(ethylene terephthalate coatings were made of a thin grinding waste produced by a PET recycling company, and of a PET powder, which was obtained by grinding post-consumer beverage bottles. Some grinding conditions, using a ceramic ball mill, were studied. Scanning Electronic Microscopy (SEM and optical microscopy (OM were used in the study of powder and coating morphologies, and this analysis showed that PET coating presents bubbles due to polymer degradation. PET powder and coating characteristics were investigated using Differential Scanning Calorimetry (DSC and measurements of intrinsic viscosity. It was observed that

  13. Corrosion resistant coating

    Science.gov (United States)

    Wrobleski, Debra A.; Benicewicz, Brian C.; Thompson, Karen G.; Bryan, Coleman J.

    1997-01-01

    A method of protecting a metal substrate from corrosion including coating a metal substrate of, e.g., steel, iron or aluminum, with a conductive polymer layer of, e.g., polyaniline, coating upon said metal substrate, and coating the conductive polymer-coated metal substrate with a layer of a topcoat upon the conductive polymer coating layer, is provided, together with the resultant coated article from said method.

  14. Low Energy Atomic Photodesorption from Organic Coatings

    Directory of Open Access Journals (Sweden)

    Alessandro Lucchesini

    2016-10-01

    Full Text Available Organic coatings have been widely used in atomic physics during the last 50 years because of their mechanical properties, allowing preservation of atomic spins after collisions. Nevertheless, this did not produce detailed insight into the characteristics of the coatings and their dynamical interaction with atomic vapors. This has changed since the 1990s, when their adsorption and desorption properties triggered a renewed interest in organic coatings. In particular, a novel class of phenomena produced by non-destructive light-induced desorption of atoms embedded in the coating surface was observed and later applied in different fields. Nowadays, low energy non-resonant atomic photodesorption from organic coatings can be considered an almost standard technique whenever large densities of atomic vapors or fast modulation of their concentration are required. In this paper, we review the steps that led to this widespread diffusion, from the preliminary observations to some of the most recent applications in fundamental and applied physics.

  15. Influence of the Discharge Voltage during Pulse-Plasma Process on the Durability of Edges coated with Superhard Coatings

    Institute of Scientific and Technical Information of China (English)

    Maciej Kupczyk

    2004-01-01

    In the paper the experimental results concerning the functional quality of thin, superhard coatings produced on cutting edges is described. Boron nitride coatings were deposited on insert cutting edges made cemented carbides by the pulse-plasma method. The comparative investigations of mentioned coatings have been concerned of tool life of edges during steel machining. In these investigations for the purpose of additional increase of coated edge durability an interfacial layers were applied. Presented investigations particularly pointed out to essential influence of the values of discharge voltage on the coating structure and durability of edges coated with boron nitride.

  16. Influence of the Discharge Voltage during Pulse-Plasma Process on the Durability of Edges coated with Superhard Coatings

    Institute of Scientific and Technical Information of China (English)

    MaciejKupczyk

    2004-01-01

    In the paper the experimental results concerning the functional quality of thin, superhard coatings produced on cutting edges is described. Boron nitride coatings were deposited on insert cutting edges made cemented carbides by the pulse-plasma method. The comparative investigations of mentioned coatings have been concerned of tool life of edges during steel machining. In these investigations for the purpose of additional increase of coated edge durability an interfacial layers were applied. Presented investigations particularly pointed out to essential influence of the values of discharge voltage on the coating structure and durability of edges coated with boron nitfide.

  17. Graphene based anticorrosive coatings for Cr(VI) replacement.

    Science.gov (United States)

    Aneja, Karanveer S; Bohm, Sivasambu; Khanna, A S; Bohm, H L Mallika

    2015-11-14

    Corrosion has been a perennial issue of concern for the steel industry. Chromate conversion coatings are well known pre-treatment coatings for steel but due to environmental concerns and legislations, their use has been restricted. The industrial community, pegged by these legislations, has been long demanding an economically viable and eco-friendly pre-treatment coating alternative, without having to compromise on the durability and corrosion performance of the overall coating system. The present study focuses on evaluation of graphene as an anticorrosive alternative to Cr(VI) based coatings. Graphene, produced by a high shear liquid exfoliation route, upon functionalisation, provides a conductive and nearly impermeable barrier coating. On electrochemical and coating performance evaluation of this coating system, a dramatic improvement in corrosion resistance is observed. The study confirms the environment friendly corrosion protection of steel using functionalised graphene coating.

  18. Nanosilica-Chitosan Composite Coating on Cotton Fabrics

    Science.gov (United States)

    Maharani, Dina Kartika; Kartini, Indriana; Aprilita, Nurul Hidayat

    2010-10-01

    Nanosilica-chitosan composite coating on cotton fabrics has been prepared by sol-gel method. The sol-gel procedure allows coating of material on nanometer scale, which several commonly used coating procedure cannot achieve. In addition, sol-gel coating technique can be applied to system without disruption of their structure functionaly. The coating were produced via hidrolysis and condensation of TEOS and GPTMS and then mixed with chitosan. The composite coating on cotton fabrics were characterized with X-Ray Diffraction and Scanning Electron microscopy (SEM) method. The result showed that the coating not changed or disrupted the cotton stucture. The coating result in a clear transparent thin layer on cotton surface. The nanocomposite coating has new applications in daily used materials, especially those with low heat resistance, such as textiles and plastics, and as an environmentally friendly water-repellent substitute for fluorine compounds.

  19. Optimization of the deposition process of corrosion resistant Stellite 6 coatings produced by laser cladding; Optimizacion del proceso de aporte de recubrimientos anticorrosion de Stellite 6 producidos mediante plaqueado laser

    Energy Technology Data Exchange (ETDEWEB)

    Vicario, I.; Soriano, C.; Sanz, C.; Bayon, R.; Leunda, J.

    2009-07-01

    Laser cladding is one of the most efficient surface treatment technologies in the industry. It uses a laser heat source to deposit a thin layer of a desired material on a moving substrate, whose properties have to be improved, achieving a metallurgical bonding between them with low heat affected zone and low dilution, compared to other conventional technologies such as PTA, TIG welding or thermal Spraying. In this sense, it is remarkable that there are 3 main application fields for laser cladding technology: restoration of refurbishment of damaged parts, surface coating against corrosion or wear, and rapid proto typing. the present work described a study of the optimization of the laser cladding of Co based coatings (Diamalloy 4060NS) on medium carbon steel C45 (AISI 1945). After laser treatment, the surface of the substrate materials is improved in terms of resistance against corrosion; this confirmed in the analysis performed afterwards. it is also shown that the corrosion barrier properties have direct correlation with the laser cladding variables. (Author) 10 refs.

  20. Coatings and Corrosion Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The mission of the Coatings and Corrosion Laboratory is to develop and analyze the effectiveness of innovative coatings test procedures while evaluating the...

  1. Carbon Coating Of Copper By Arc-Discharge Pyrolysis

    Science.gov (United States)

    Ebihara, Ben T.; Jopek, Stanley

    1988-01-01

    Adherent, abrasion-resistant coat deposited with existing equipment. Carbon formed and deposited as coating on copper substrate by pyrolysis of hydrocarbon oil in electrical-arc discharges. Technique for producing carbon deposits on copper accomplished with electrical-discharge-machining equipment used for cutting metals. Applications for new coating technique include the following: solar-energy-collecting devices, coating of metals other than copper with carbon, and carburization of metal surfaces.

  2. Processing and properties of electrodeposited layered surface coatings

    DEFF Research Database (Denmark)

    Horsewell, Andy

    1998-01-01

    clacks and spalls off early on. For thick, non-compliant coatings, much thicker coatings can be formed. Fracture resistance must be considered in relation to both specimen and loading geometries. Since the inherent bending moment causes a maximum tensile stress at the coating surface, the loading......Hard chromium, produced by conventional dir ect curl ent (DC) electrodeposition, cannot be deposited to thicknesses gl enter than about 5 mu m because of the buildup of processing stresses which cause channel cracks in the coating. Much thicker chromium coatings map be produced by depositing...... a layered structure using alternate DC plating and periodic current reversal (PR). Such layering produces a through thickness stepped gradient in residual stresses. Most importantly a bending moment develops in the coating whenever the substrate is compliant. For thin, compliant substrates, the coating...

  3. Corrosion-resistant coating development

    Energy Technology Data Exchange (ETDEWEB)

    Stinton, D.P.; Kupp, D.M.; Martin, R.L. [Oak Ridge National Lab., TN (United States)

    1997-12-01

    SiC-based heat exchangers have been identified as the prime candidate material for use as heat exchangers in advanced combined cycle power plants. Unfortunately, hot corrosion of the SiC-based materials created by alkali metal salts present in the combustion gases dictates the need for corrosion-resistant coatings. The well-documented corrosion resistance of CS-50 combined with its low (and tailorable) coefficient of thermal expansion and low modulus makes CS-50 an ideal candidate for this application. Coatings produced by gelcasting and traditional particulate processing have been evaluated.

  4. Reduction of hematite with ethanol to produce magnetic nanoparticles of Fe{sub 3}O{sub 4}, Fe{sub 1-x}O or Fe{sup 0} coated with carbon

    Energy Technology Data Exchange (ETDEWEB)

    Tristao, Juliana C. [Universidade Federal de Minas Gerais, Departamento de Quimica-ICEx (Brazil); Ardisson, Jose D. [Centro de Desenvolvimento de Tecnologia Nuclear, CDTN, Laboratorio de Fisica Aplicada (Brazil); Sansiviero, Maria Terezinha C.; Lago, Rochel M., E-mail: rochel@ufmg.br [Universidade Federal de Minas Gerais, Departamento de Quimica-ICEx (Brazil)

    2010-01-15

    The production of magnetic nanoparticles of Fe{sub 3}O{sub 4} or Fe{sup 0} coated with carbon and carbon nanotubes was investigated by the reduction of hematite with ethanol in a Temperature Programmed Reaction up to 950 deg. C. XRD and Moessbauer measurements showed after reaction at 350 deg. C the partial reduction of hematite to magnetite. At 600 deg. C the hematite is completely reduced to magnetite (59%), wuestite (39%) and metallic iron (7%). At higher temperatures, carbide and metallic iron are the only phases present. TG weight losses suggested the formation of 3-56 wt.% carbon deposits after reaction with ethanol. It was observed by SEM images a high concentration of nanometric carbon filaments on the material surface. BET analyses showed a slight increase in the surface area after reaction. These materials have potential application as catalyst support and removal of spilled oil contaminants.

  5. An overview on novel thermal barrier coatings

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Thermal barrier coatings (TBCs) offer the potential to significantly improve efficiencies of aero engines as well as stationary gas turbines for power generation. On internally cooled turbine parts, temperature gradients of the order of 100-150℃ can be achieved. TBCs, typically consisting of an yttrium stabilized zirconia top coat and a metallic bond coat deposited onto a superalloy substrate, are mainly used to extend lifetime. Further efficiency improvements require TBCs being an integral part of the component which requires reliable and predictable TBC performance. TBCs produced by electron beam physical vapor deposition (EbPVD) or plasma spray (PS) deposition are favored for high performance applications. The paper highlights critical R&D needs for advanced TBC systems with a special focus on reduced thermal conductivity and life prediction needs. To further enhance the efficiency of gas turbines, higher temperature and a longer lifetime of the coating are needed for the next generation of TBCs. This paper presents the development of new materials, new deposition technologies, and new concept for application as novel TBCs. This paper summarizes the basic properties of conventional thermal barrier coatings. Based on our own investigation, we reviewed the progress on materials and technologies of novel thermal barrier coatings. Except yttria stabilized zirconia, other materials such as lanthanum zirconate and rare earth oxides are also promising materials for thermal barrier coatings. Nanostructure thermal barrier coating is presented as a new concept. This paper also summarizes the technologies for depositing the thermal barrier coatings.

  6. Effect of coating density on oxidation resistance and Cr vaporization from solid oxide fuel cell interconnects

    DEFF Research Database (Denmark)

    Talic, Belma; Falk-Windisch, Hannes; Venkatachalam, Vinothini

    2017-01-01

    •Protective action of dense and porous spinel coatings on Crofer 22 APU was compared. •Reduction and re-oxidation produces denser coatings than heat treating in air only. •Coating density has minor influence on oxidation resistance at 800 °C in air. •Dense coating resulted in three times lower Cr...

  7. Multi-layer coatings

    Energy Technology Data Exchange (ETDEWEB)

    Maghsoodi, Sina; Brophy, Brenor L.; Abrams, Ze' ev R.; Gonsalves, Peter R.

    2016-06-28

    Disclosed herein are coating materials and methods for applying a top-layer coating that is durable, abrasion resistant, highly transparent, hydrophobic, low-friction, moisture-sealing, anti-soiling, and self-cleaning to an existing conventional high temperature anti-reflective coating. The top coat imparts superior durability performance and new properties to the under-laying conventional high temperature anti-reflective coating without reducing the anti-reflectiveness of the coating. Methods and data for optimizing the relative thickness of the under-layer high temperature anti-reflective coating and the top-layer thickness for optimizing optical performance are also disclosed.

  8. Producing Presences

    OpenAIRE

    Mandagará, Pedro

    2008-01-01

    Resenha de MENDES, Victor K.; ROCHA, João Cezar de Castro (Eds.). Producing Presences: branching out from Gumbrecht’s work. Dartmouth, Massachusetts: University of Massachusetts Dartmouth, 2007. (Adamastor book series, 2)

  9. Oxidation and Hot Corrosion Behavior of a Composite Coating System

    Institute of Scientific and Technical Information of China (English)

    Dongbai XIE; Fuhui WANG

    2003-01-01

    The oxidation and hot corrosion behavior of Co-Ni-Cr-Al-Ta-Y coating produced by magnetron sputtering with and without enamel coating has been investigated in air at 900℃ and in molten 75 wt pct NaCl+25 wt pct Na2SO4at 850℃. The results show that the enamel coating possesses good hot corrosion resistance in the molten salts, in comparison with the sputtered Co-Ni-Cr-Al-Ta-Y coating. In the hot corrosion test, breakaway corrosion did not occur on the samples with enamel coating and the composition of enamel coating did not significantly change either. The oxidation resistance of the sputtered coating, which offers good adhesion, can be improved by the enamel coating.

  10. Electrochemical corrosion behavior of arc sprayed Zn-Al coatings

    Institute of Scientific and Technical Information of China (English)

    LIU Yan; ZHU Zi-xin; CHEN Yong-xiong; XU Bin-shi; MA Shi-ning; LI Zhuo-xin

    2004-01-01

    Cored wires and high velocity arc spraying (HVAS) technique were applied to produce high Al content Zn-Al alloy coatings on low carbon steel substrates. The electrochemical corrosion behaviors of Zn, Al and Zn-Al coatings were studied with potentiodynamic measurement in 5 % NaCl solution. Compared with pure Zn, pure Al and Zn-15Al coatings, Zn-26Al coatings show a higher corrosion resistance in salt solution. The potentiodynamic polarization tests show that the corrosion resistance of Zn-Al coatings increases as Al content is raised. Pure Al coating exhibits different electrochemical behaviors with other coatings. The corrosion initiated at the micro-pores of the coating and the underlying corrosion mechanism is very similar to that of the pitting corrosion.

  11. A novel electrostatic dry powder coating process for pharmaceutical dosage forms: immediate release coatings for tablets.

    Science.gov (United States)

    Qiao, Mingxi; Zhang, Liqiang; Ma, Yingliang; Zhu, Jesse; Chow, Kwok

    2010-10-01

    An electrostatic dry powder coating process for pharmaceutical solid dosage forms was developed for the first time by electrostatic dry powder coating in a pan coater system. Two immediate release coating compositions with Opadry® AMB and Eudragit® EPO were successfully applied using this process. A liquid plasticizer was sprayed onto the surface of the tablet cores to increase the conductivity of tablet cores to enhance particle deposition, electrical resistivity reduced from greater than 1×10(13)Ωm to less than 1×10(9)Ωm, and to lower the glass transition temperature (T(g)) of the coating polymer for film forming in the pan coater. The application of liquid plasticizer was followed by spraying charged coating particles using an electrostatic charging gun to enhance the uniform deposition on tablet surface. The coating particles were coalesced into a thin film by curing at an acceptable processing temperature as formation was confirmed by SEM micrographs. The results also show that the optimized dry powder coating process produces tablets with smooth surface, good coating uniformity and release profile that are comparable to that of the tablet cores. The data also suggest that this novel electrostatic dry powder coating technique is an alternative to aqueous- or solvent-based coating process for pharmaceutical products. Crown Copyright © 2010. Published by Elsevier B.V. All rights reserved.

  12. Analytical Modeling of Hard-Coating Cantilever Composite Plate considering the Material Nonlinearity of Hard Coating

    Directory of Open Access Journals (Sweden)

    Wei Sun

    2015-01-01

    Full Text Available Due to the material nonlinearity of hard coating, the coated structure produces the nonlinear dynamical behaviors of variable stiffness and damping, which make the modeling of hard-coating composite structure become a challenging task. In this study, the polynomial was adopted to characterize this material nonlinearity and an analytical modeling method was developed for the hard-coating composite plate. Firstly, to relate the hard-coating material parameters obtained by test and the analytical model, the expression of equivalent strain of composite plate was derived. Then, the analytical model of hard-coating composite plate was created by energy method considering the material nonlinearity of hard coating. Next, using the Newton-Raphson method to solve the vibration response and resonant frequencies of composite plate and a specific calculation procedure was also proposed. Finally, a cantilever plate coated with MgO + Al2O3 hard coating was chosen as study case; the vibration response and resonant frequencies of composite plate were calculated using the proposed method. The calculation results were compared with the experiment and general linear calculation, and the correctness of the created model was verified. The study shows the proposed method can still maintain an acceptable precision when the material nonlinearity of hard coating is stronger.

  13. METAL-CERAMIC INTERFACES PRODUCED BY LASER MELT INJECTION PROCESSING

    NARCIS (Netherlands)

    DEHOSSON, JTM; VANDENBURG, M; Burg, M. van den

    1995-01-01

    This paper concentrates on the mechanical performance of various ceramic coatings of Cr2O3 on steel (SAF2205), as produced by CO2 laser processing. It is concluded that a firmly bonded coating of Cr2O3 on steel could be produced by high power laser processing. The actual interface strength of a

  14. METAL-CERAMIC INTERFACES PRODUCED BY LASER MELT INJECTION PROCESSING

    NARCIS (Netherlands)

    DEHOSSON, JTM; VANDENBURG, M; Burg, M. van den

    1995-01-01

    This paper concentrates on the mechanical performance of various ceramic coatings of Cr2O3 on steel (SAF2205), as produced by CO2 laser processing. It is concluded that a firmly bonded coating of Cr2O3 on steel could be produced by high power laser processing. The actual interface strength of a (Fe,

  15. Development of Bioactive Ceramic Coating on Titanium Alloy substrate for Biomedical Application Using Dip Coating Method

    Science.gov (United States)

    Asmawi, R.; Ibrahim, M. H. I.; Amin, A. M.; Mustafa, N.; Noranai, Z.

    2017-08-01

    Bioactive apatite, such as hydroxyapatite ceramic (HA), [Ca10(PO4)6(OH)2] has been extensively investigated for biomedical applications due to its excellent biocompatibility and tissue bioactivity properties. Its bioactivity provides direct bonding to the bone tissue. Because of its similarity in chemical composition to the inorganic matrix of bone, HA is widely used as implant materials for bone. Unfortunately, because of its poor mechanical properties,. this bioactive material is not suitable for load bearing applications. In this study, by the assistance of dip-coating technique, HA coatings were deposited on titanium alloy substrates by employing hydrothermal derived HA powder. The produced coatings then were oven-dried at 130°C for 1 hour and calcined at various temperature over the range of 200-800°C for 1 hour. XRD measurement showed that HA was the only phase present in the coatings. However coatings calcined at 800°C comprised a mixture of HA and tri-calcium phosphate (TCP). FTIR measurement showed the existence of hydroxyl, phosphate, and carbonate bands. PO4 - band became sharper and narrower with the increased of calcination temperature. FESEM observation showed that the coating is polycrystalline with individual particles of nano to submicron size and has an average particle size of 35 nm. The thickness of the coating are direcly propotional with the viscosity of coating slurry. It was shown that the more viscous coating slurry would produce a thicker ceramic coating. Mechanical properties of the coating were measured in term of adhesion strength using a Micro Materials Nano Test microscratch testing machine. The result revealed that the coating had a good adhesion to the titanium alloy substrate.

  16. Platinum and Iridium Coatings Obtained by Double Glow Plasma Technology

    Institute of Scientific and Technical Information of China (English)

    WU Wangping; CHEN Zhaofeng; CHEN Zhou; CONG Xiangna; QIU Jinlian

    2012-01-01

    Pt and Ir coatings were produced by double glow plasma technology on the surface of Ti alloy substrates.The chemical compositions of the coatings were determined by X-ray diffraction and X-ray photoelectron spectroscopy.The microstructure and morphology of the coatings were observed by scanning electron microscopy.The hardness and elastic modulus of the coatings were estimated by nanoindentation.The measurements of adhesive forces of the coatings were performed with scratch tester.The results indicated that the Pt and Ir coatings displayed the preferred (220) orientation due to the initial nuclei with preferred growth on the surface of the substrates.The interface between the Pt coating and substrate exhibited no evidence of delamination.The Ir coating was composed of irregular columnar grains with many nanovoids at the interface between the coating and substrate.The mean values of hardness for Pt and Ir coatings were 0.9 GPa and 9 GPa,respectively.The elastic modulus of Pt and Ir coatings were 178 GPa and 339 GPa,respectively.The adhesive forces of the Pt and Ir coatings were about 66.4 N and 55 N,respectively.The Pt and Ir coatings adhered well to the Ti alloy substrates.

  17. Alternative HTS coated conductors

    Science.gov (United States)

    Blaugher, R. D.; Bhattacharya, R. N.; Chen, J.; Padmanabhan, R.

    2002-10-01

    The availability of Bi-2223 high-temperature-superconductor (HTS) powder-in-tube (PIT) tape, with acceptable performance for long lengths, has provided the ability to construct a wide range of HTS electric power components. As a result, there are major worldwide projects in developing HTS electric power components for demonstration in a utility environment. Utility acceptance for superconducting power equipment will depend on several key factors: improved system performance, lower life-cycle costs, higher efficiency versus conventional technology, reliability and maintenance comparable to conventional power equipment, and a competitive installed cost. The latter is impacted by the current high cost of HTS conductors, which must be lowered to costs comparable to conventional Nb-Ti wire, i.e., $2-5/kAm. The present performance and cost of state-of-the-art Bi-2223 HTS tape, although acceptable for prototype construction, is viewed as a major deterrent that may compromise eventual commercialization for most of these electric power devices. The so-called second-generation coated conductor development, with emphasis on conductors employing HTS YBCO films, is viewed as the solution to this performance and cost issue. The potential for the Tl, Hg, and Bi-oxide superconductors for producing an HTS tape as alternatives to Bi-2223 PIT (and YBCO) will be discussed with some recent results on Bi-2212 “coated conductor” development.

  18. Next Generation Thermal Barrier Coatings for the Gas Turbine Industry

    Science.gov (United States)

    Curry, Nicholas; Markocsan, Nicolaie; Li, Xin-Hai; Tricoire, Aurélien; Dorfman, Mitch

    2011-01-01

    The aim of this study is to develop the next generation of production ready air plasma sprayed thermal barrier coating with a low conductivity and long lifetime. A number of coating architectures were produced using commercially available plasma spray guns. Modifications were made to powder chemistry, including high purity powders, dysprosia stabilized zirconia powders, and powders containing porosity formers. Agglomerated & sintered and homogenized oven spheroidized powder morphologies were used to attain beneficial microstructures. Dual layer coatings were produced using the two powders. Laser flash technique was used to evaluate the thermal conductivity of the coating systems from room temperature to 1200 °C. Tests were performed on as-sprayed samples and samples were heat treated for 100 h at 1150 °C. Thermal conductivity results were correlated to the coating microstructure using image analysis of porosity and cracks. The results show the influence of beneficial porosity on reducing the thermal conductivity of the produced coatings.

  19. Microstructural investigation of phases and pinning properties in MBa2Cu3O7-x (M = Y and/or Gd) coated conductors produced by scale-up facilitie

    Science.gov (United States)

    Jin, Hye-Jin; Moon, Han-Kyoul; Yoon, Seokhyun; Jo, William; Kim, Kunsu; Kim, Miyoung; Ko, Rock-Kil; Jo, Young-Sik; Ha, Dong-Woo

    2016-03-01

    To expedite the commercialization of coated conductors, a robust stacking architecture of the wires must be developed and the performance of the critical currents improved. More importantly, the manufacturability, or large-scale delivery, and the capability of sustaining production at a high rate must be considered. The products of three companies, American Superconductor, Superpower Inc., and SuNAM Co., Ltd, were selected because these companies have announced commercial-grade production lines and delivered a significant amounts of wires to the open market that meet the standards demanded by power devices. X-ray diffraction patterns were used to verify the structural properties and the phase formation in the wires, and transmission electron microscopy with energy dispersive spectroscopy was used to investigate the microstructure and composition of the conductors. In addition, Raman scattering spectroscopy was used for the analysis of the phase formation and for the elucidation of secondary phases in the superconducting layers. The field dependence of the critical current was also studied to compare the transport characteristics under relatively low and medium magnetic field at 77 K and 60 K. Pinning forces were obtained from the field dependence of transport properties and pinning characteristics were investigated. The theoretical and experimental analyses were combined together using the Dew-Hughes formula to extract the scaling exponents and estimate the irreversibility lines of the fields. The results showed that the three conductors possess pinning mechanisms that originate from core pinning with a surface pinning geometry. It is remarkable that the wires discussed in this paper exhibit very similar pinning characteristics even though they have different characteristics in terms of chemical composition, microstructure, stacking architectures, and distribution of parasitic phases.

  20. Coating of pumps; coating af pumper

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Hans; Moritzen, J.; Thoegersen, Jeanette

    2005-11-15

    Coating of pumps is a quite new activity. For many years pipes and containers have been coated inside in order to avoid corrosion, but the technology has only been used inside pumps for the last ten years. The technology comes from USA and is originally developed in the space technology industry as an exceptionally durable and corrosion constant coating. The project is a further development of results found in a previous R and D project in which measurements were performed before and after coating two different installations. Both installations showed large efficiency improvements. This project supplements the theory behind losses in pumps with measurements on more pumps. (BA)

  1. New sol–gel refractory coatings on chemically-bonded sand cores for foundry applications to improve casting surface quality

    DEFF Research Database (Denmark)

    Nwaogu, Ugochukwu Chibuzoh; Poulsen, T.; Stage, R.K.

    2011-01-01

    Foundry refractory coatings protect bonded sand cores and moulds from producing defective castings during the casting process by providing a barrier between the core and the liquid metal. In this study, new sol–gel refractory coating on phenolic urethane cold box (PUCB) core was examined....... The coating density, viscosity, moisture content and wet and dry weight of the coating were evaluated on cores that had been coated at three different dip-coating times. The coating coverage, surface appearance and depth of penetration into the cores were examined with a Stereomicroscope. Gray iron castings...... were produced with sol-gel coated and uncoated cores and the results were related to the coating properties. The casting results were also compared with castings made with cores coated with commercial alcohol-based and water-based foundry coatings. The analyses show that castings produced with sol...

  2. Novel nanostructured hydroxyapatite coating for dental and orthopedic implants

    Science.gov (United States)

    Liu, Huinan; Jiang, Wenping; Malshe, Ajay

    2009-09-01

    A novel hybrid coating process, combining NanoSpray® (built on electrostatic spray coating) technology with microwave sintering process, was developed for synthesizing hydroxyapatite- (HA-) based nanostructured coating with favorable properties for dental and orthopedic implants. Specifically, HA nanoparticles were deposited on commercially pure titanium substrates using NanoSpray technique to produce the HA coating, which was then sintered in a microwave furnace under controlled conditions. The study showed that the use of NanoSpray followed by microwave sintering results in nanoscale HA coating for dental/orthopedic application.

  3. SYNTHESIS AND COATING OF ORDERED MESOPOROUS SILICA

    Institute of Scientific and Technical Information of China (English)

    Wei Guo; Guangsheng Luo; Yujun Wang

    2003-01-01

    1,3,5-trimethyl benzene (TMB) was used as organic swelling agent in O/W emulsions to template ultra-large mesoporous materials using the hydrothermal method. The silicas with well-defined mesopores and hydrothermally robust framework were characterized by X-ray diffraction, transmission electron microscopy and BET surface area analysis. The influence of the quantity of TMB during preparation was studied. It has been found that the TMB/CTAB ratio must be controlled for producing high pore volume materials. Polysulfone (PSU), as the usual extraction agent, was coated on the silicas with the solvent evaporation method to produce a solid separation medium. The adsorptivity and the surface area of the coated MCM were determined: 10% PSU coated MCM adsorbed twice as much phenol as the uncoated material, reaching 0.5 mg/g silica. It was found that the surface area of the coated material decreased rapidly with an increase of the PSU loading.

  4. Steam generated conversion coating on aluminium alloys

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Jellesen, Morten Stendahl; Ambat, Rajan

    pressure steam produced by an autoclave at a temperature of 107 – 121 °C and pressure of 15 -17 psi for 10 minutes to produce a thin coating of aluminium oxide. The aim of this study is to understand the effect of high pressure steam with and without different chemical additives on surface morphology...

  5. "m=1" coatings for neutron guides

    OpenAIRE

    Cooper-Jensen, C.P.; Vorobiev, A.; Klinkby, Esben Bryndt; Kapaklis, V.; Wilkens, H.; Rats, D.; Hjörvarsson, B.; Kirstein, O.; Bentley, Philip

    2014-01-01

    A substantial part of the price for a neutron guide is the shielding needed because of the gamma ray produced when neutrons are absorbed. This absorption occurs in the coating and the substrate of the neutron guides. Traditional m=1 coatings have been made of Ni and if reflectivity over the critical angle of Ni is needed one has used Ni58 or Ni/Ti multilayer coatings. Ni has one of the highest neutron scattering density but it also has a fairly high absorption cross section for cold and therm...

  6. Hydrotreating Pyrolytic Lignin to Produce a Refinery Feedstock (Poster)

    Energy Technology Data Exchange (ETDEWEB)

    French, R. J.

    2013-09-01

    Fast pyrolysis of biomass followed by water separation to produce pyrolytic lignin and hydrotreating of the lignin could be used to produce a stable volatile low-oxygen intermediate liquid. Such a liquid could be converted into a finished motor-fuel in a refinery, taking advantage of the existing infrastructure and economies of scale of refineries. Hydrotreating just the lignin would consume less hydrogen while preserving about half of the energy of the original oil. The aqueous by-products could be reformed to produce the needed hydrogen and would contain much of the unwanted acids and unstable oxygenates. To assess such intermediate liquids, several pyrolytic lignins were prepared by mixing pyrolysis oil with water at 1:1 and 3:1 ratios. The carboxylic acidity in the pyrolytic lignin was reduced to 24 and 10 mg-KOH/g-lignin compared to 81 in the whole oil. These lignins were hydrotreated using Ni-Mo(S)/alumina, Pt/char, or Pd/C(activated) in a semi-batch 1 L stirred autoclave. The oil was stabilized under hydrogen at 150-280 degrees C, then water and light organics were removed by partial depressurization. Hydrodeoxygenation was then performed at 340-400 degrees C. Total pressure was controlled at 70 or 170 bar with hydrogen gas. Organic liquid yields of 39-56% were obtained. For many experiments the organic oxygen content was <7%, acidity was < 7 mg-KOH/g-oil, the volatility was greater than or equal to 94% and, on a carbon basis, the total yield of organic products miscible in hydrocarbons at a 1:10 ratio was over 50%. These properties are probably acceptable to a refinery.The residual liquids left in the reactor at the end of the experiment comprised 60-85% of the organic-phase product while the rest was condensate. 13C-NMR of the residual liquids showed that they were 50-80% aliphatic. 13C-NMR coupled with GC-MS identified phenolic compounds as the main oxygenates in most residual liquids.

  7. Novel ormocers and nanomers for coatings

    OpenAIRE

    Oliveira, Peter William de; Schmidt, Helmut K.; Sepeur, Stefan

    1999-01-01

    Nanoparticles produced by a microemulsion for a controlled growth precipitation technique (ZrO2, AlOOH) have been surface modified and incorporated into inorganic/organic composite matrices made from epoxy or methacryloxy silanes. For this reason, the nanopowders have been surface modified with carboxylic acids in order to obtain full dispersibility necessary for high optical quality coatings. ZrO2 was used for obtaining high refractive index coatings. By adjusting an appropriate zeta-potenti...

  8. Enhanced photothermal effect of plasmonic nanoparticles coated with reduced graphene oxide.

    Science.gov (United States)

    Lim, Dong-Kwon; Barhoumi, Aoune; Wylie, Ryan G; Reznor, Gally; Langer, Robert S; Kohane, Daniel S

    2013-09-11

    We report plasmonic gold nanoshells and nanorods coated with reduced graphene oxide that produce an enhanced photothermal effect when stimulated by near-infrared (NIR) light. Electrostatic interactions between nanosized graphene oxide and gold nanoparticles followed by in situ chemical reduction generated reduced graphene oxide-coated nanoparticles; the coating was demonstrated using Raman and HR-TEM. Reduced graphene oxide-coated gold nanoparticles showed enhanced photothermal effect compared to noncoated or nonreduced graphene oxide-coated gold nanoparticles. Reduced graphene oxide-coated gold nanoparticles killed cells more rapidly than did noncoated or nonreduced graphene oxide-coated gold nanoparticles.

  9. Surfaces, Coatings and Protection

    Science.gov (United States)

    Ferguson, I. F.

    1982-08-01

    Plasma sprayed ceramics, sputter ion plating, and sol-gel ceramic protective coatings for nuclear reactors are discussed. The influence of such coatings on the behavior of reactor fuel elements is noted. The investigation of such coatings by diffraction methods is described. Laser and nuclear microprobes, scanning transmission electron microscopes, neutron scattering, and image analysis are summarized.

  10. Commercial Fastener Coatings Doerken

    Science.gov (United States)

    2010-06-01

    Phosphating* *partly recommended Dip Spinning Dipping Spraying Spin coating Conveyor oven box oven Inductive drying Pretreatment Coating Preheating...Curing Cooling Application Techniques - Dip Spin Coating Gurtbnd Cross BarTranspo" Band beiCifteiE Vo12one Vent llated Pre .Zone Cros~ Bar T ransrt

  11. PIT Coating Requirements Analysis

    Energy Technology Data Exchange (ETDEWEB)

    MINTEER, D.J.

    2000-10-20

    This study identifies the applicable requirements for procurement and installation of a coating intended for tank farm valve and pump pit interior surfaces. These requirements are intended to be incorporated into project specification documents and design media. This study also evaluates previously recommended coatings and identifies requirement-compliant coating products.

  12. Nanocrystalline hydroxyapatite/titania coatings on titanium improves osteoblast adhesion.

    Science.gov (United States)

    Sato, Michiko; Aslani, Arash; Sambito, Marisa A; Kalkhoran, Nader M; Slamovich, Elliott B; Webster, Thomas J

    2008-01-01

    Bulk hydroxyapatite (HA) and titania have been used to improve the osseointegration of orthopedic implants. For this reason, composites of HA and titania have been receiving increased attention in orthopedics as novel coating materials. The objective of this in vitro study was to produce nanophase (i.e., materials with grain size less than 100 nm) HA/titania coatings on titanium. The adhesion of bone forming cells (osteoblasts) on the composite coatings were also assessed and compared with single-phase nanotitania and nano-HA titanium coatings. Nanocrystalline HA powders were synthesized through wet chemistry and hydrothermal treatments at 200 degrees C. Nanocrystalline titania powders obtained commercially were mixed with the nanocrystalline HA powders at various weight ratios. The mixed powders were then deposited on titanium utilizing a room-temperature coating process called IonTite. The results of the present study showed that such coatings maintained the chemistry and crystallite size of the original HA and titania powders. Moreover, osteoblasts adherent on single-phase nanotitania coatings were well-spread whereas they became more round and extended distinct filopodia on the composite and single-phase HA coatings. Interestingly, the number of osteoblasts adherent on the nanotitania/HA composite coatings at weight ratios of 2/1 and 1/2 were significantly greater compared with single-phase nanotitania coatings, currently-used plasma-sprayed HA coatings, and uncoated titanium. These findings suggest that nanotitania/HA coatings on titanium should be further studied for improved orthopedic applications.

  13. Characterization of titanium–hydroxyapatite biocomposites processed by dip coating

    Indian Academy of Sciences (India)

    R Baptista; D Gadelha; M Bandeira; D Arteiro; M I Delgado; A C Ferro; M Guedes

    2016-02-01

    Ti orthopaedic implants are commonly coated with hydroxyapatite (HA) to achieve increased biocompatibility and osseointegration with natural bone. In this work the dip-coating technique was used to apply HA films on Ti foil. A gel was used as the support vehicle for commercial HA particles. The experimental parameters like surface roughness of the metallic substrate and immersion time were studied. All coated substrates were heat treated and sintered under vacuum atmosphere. The produced coatings were characterized by field-emission gun scanning electron microscopy coupled with energy-dispersive spectroscopy, X-ray diffraction, Raman spectroscopy, microhardness, scratch test and profilometry. Additionally, the apatite-forming ability of the produced material was tested by exposure to a simulated body fluid. Higher substrate surface roughness and longer immersion time produce thicker, denser films, with higher surface roughness. Lower film porosity is accompanied by higher hardness values. However, thicker coating promotes differential shrinkage and crack formation during sintering. Both coating thickness and coating roughness increase with coating time. HA films $\\sim$30–40 $\\mu$m thick with 45–50% HA theoretical density produced on Ti substrates with surface roughness of $R_z\\sim 1.0–1.7$ $\\mu$m, display an attractive combination of high hardness and resistance to spallation. Attained results are encouraging regarding the possibility of straightforward production of biocompatible and bioactive prosthetic coatings for orthopaedic applications using commercial HA.

  14. Hard and superhard nanocomposite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Musil, J. [Univ. of West Bohemia, Plzen (Czech Republic). Dept. of Phys.

    2000-03-01

    This article reviews the development of hard coatings from a titanium nitride film through superlattice coatings to nanocomposite coatings. Significant attention is devoted to hard and superhard single layer nanocomposite coatings. A strong correlation between the hardness and structure of nanocomposite coatings is discussed in detail. Trends in development of hard nanocomposite coatings are also outlined. (orig.)

  15. Nanosilica coating for bonding improvements to zirconia

    Directory of Open Access Journals (Sweden)

    Chen C

    2013-10-01

    Full Text Available Chen Chen, Gang Chen, Haifeng Xie, Wenyong Dai, Feimin Zhang Institute of Stomatology, Nanjing Medical University, Nanjing, Jiangsu Province, People's Republic of China Abstract: Resin bonding to zirconia cannot be established from standard methods that are currently utilized in conventional silica-based dental ceramics. The solution–gelatin (sol–gel process is a well developed silica-coating technique used to modify the surface of nonsilica-based ceramics. Here, we use this technique to improve resin bonding to zirconia, which we compared to zirconia surfaces treated with alumina sandblasting and tribochemical silica coating. We used the shear bond strength test to examine the effect of the various coatings on the short-term resin bonding of zirconia. Furthermore, we employed field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, atomic force microscopy, and Fourier transform infrared spectroscopy to characterize the zirconia surfaces. Water–mist spraying was used to evaluate the durability of the coatings. To evaluate the biological safety of the experimental sol–gel silica coating, we conducted an in vitro Salmonella typhimurium reverse mutation assay (Ames mutagenicity test, cytotoxicity tests, and in vivo oral mucous membrane irritation tests. When compared to the conventional tribochemical silica coating, the experimental sol–gel silica coating provided the same shear bond strength, higher silicon contents, and better durability. Moreover, we observed no apparent mutagenicity, cytotoxicity, or irritation in this study. Therefore, the sol–gel technique represents a promising method for producing silica coatings on zirconia. Keywords: zirconia, bond, silica coating, tribochemical silica coating, biocompatibility

  16. Wrinkling of solidifying polymeric coatings

    Science.gov (United States)

    Basu, Soumendra Kumar

    2005-07-01

    In coatings, wrinkles are viewed as defects or as desired features for low gloss, and texture. In either case, discovering the origin of wrinkles and the conditions that lead to their formation is important. This research examines what wrinkling requires and proposes a mechanism to explain the observations. All curing wrinkling coatings contain multi-functional reactants. Upon curing, all develop a depth-wise gradient in solidification that result in a cross-linked elastic skin atop a viscous bottom layer. It is hypothesized that compressive stress develops in the skin when liquid below diffuses up into the skin. High enough compressive stress buckles the skin to produce wrinkles. The hypothesis is substantiated by experimental and theoretical evidences. Effects of various application and compositional parameters on wrinkle size in a liquid-applied acrylic coating and a powder-applied epoxy coating were examined. All three components, namely resin, cross-linker and catalyst blocked with at least equimolar volatile blocker, proved to be required for wrinkling. The wrinkling phenomenon was modeled with a theory that accounts for gradient generation, cross-linking reaction and skinning; predictions compared well with observations. Two-layer non-curing coatings that have a stiff elastic layer atop a complaint elastic bottom layer wrinkled when the top layer is compressed. The top layer was compressed by either moisture absorption or differential thermal expansion. Experimental observations compared well with predictions from a theory based on force balance in multilayer systems subjected to differential contraction or expansion. A model based on the Flory-Rehner free energy of a constrained cross-linked gel was constructed that predicts the compressive stress generated in a coating when it absorbs solvent. Linear stability analysis predicts that when a compressed elastic layer is attached atop a viscous layer, it is always unstable to buckles whose wavelength exceeds a

  17. Synthesis of Superhydrophobic Nanocomposite Coatings Using Electrodeposition

    Science.gov (United States)

    Iacovetta, Daniel John

    The focus of the current research is to produce a metal matrix composite material that possesses a superhydrophobic surface using electrodeposition. The objective is to create a multifunctional coating that is able to provide high strength as well as high water repellency using nanocrystalline nickel and polytetrafluoroethylene (PTFE) particles. The co-deposition process was first studied. It was determined that the amount of PTFE co-deposited is highly dependent on the concentration of PTFE particles in the electroplating bath. The wetting angle of the surface greatly increased when the PTFE content increases. Next the electroplating procedure of pure nickel is altered to produce a nanocrystalline material, resulting in a large increase in the hardness of the nickel coatings. The two techniques are combined to produce a nanocrystalline Nickel-PTFE composite. Under optimum conditions, the composite coating displayed a highly water repellent surface and improved mechanical properties.

  18. Development of high viscosity coatings for advanced Space Shuttle applications

    Science.gov (United States)

    Garofalini, S. H.; Banas, R.; Creedon, J.

    1979-01-01

    Laboratory studies for increasing the thermal resistance of high viscosity coatings for silica reusable surface insulation are presented. The coatings are intended for the reentry temperature associated with advanced Space Shuttle applications which will involve aerodynamic shear forces during entry from earth orbits. Coating viscosity was increased by (1) reduction in the concentration of the low viscosity additive B2O3; (2) reduction in the particle size of the constituent powders in coatings; and (3) addition of a high viscosity glass former (GeO2). A coating system was produced by combining the three methods which showed apparent higher viscosity than the current coating, while satisfying all the current Shuttle Orbiter coating requirements.

  19. Application of thermal barrier coating in a Diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Buyukkaya, E. [Dept. of Mechanical Engineering, Sakarya Univ., Sakarya (Turkey); Demirkiran, A.S. [Dept. of Metallurgical and Materials Science Engineering, Sakarya Univ., Sakarya (Turkey); Cerit, M.

    2004-07-01

    In this study, an investigation of the effects of ceramic coatings on Diesel engine performance and exhaust emissions was presented. Tests were carried out a range of engine speeds at low, middle and high load conditions for a standard engine and a ceramic-coated engine. Cylinder head and valves of an engine were coated with a 0.35 mm thickness of CaZrO{sub 3} over a 0.15 mm thickness of NiCrAl bond coat. Pistons were also coated with MgZrO{sub 3}. The coatings were produced using atmospheric plasma spray technique. Specific fuel consumption values of insulated engine were lower than standard engine (about 1-6%). Due to the better combustion efficiency in the coated engine, particulate emissions were lower than the standard engine (about 48%). (orig.)

  20. Antibacterial polymer coatings.

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Mollye C.; Allen, Ashley N.; Barnhart, Meghan; Tucker, Mark David; Hibbs, Michael R.

    2009-09-01

    A series of poly(sulfone)s with quaternary ammonium groups and another series with aldehyde groups are synthesized and tested for biocidal activity against vegetative bacteria and spores, respectively. The polymers are sprayed onto substrates as coatings which are then exposed to aqueous suspensions of organisms. The coatings are inherently biocidal and do not release any agents into the environment. The coatings adhere well to both glass and CARC-coated coupons and they exhibit significant biotoxicity. The most effective quaternary ammonium polymers kills 99.9% of both gram negative and gram positive bacteria and the best aldehyde coating kills 81% of the spores on its surface.

  1. ALD Produced B{sub 2}O{sub 3}, Al{sub 2}O{sub 3} and TiO{sub 2} Coatings on Gd{sub 2}O{sub 3} Burnable Poison Nanoparticles and Carbonaceous TRISO Coating Layers

    Energy Technology Data Exchange (ETDEWEB)

    Weimer, Alan

    2012-11-26

    This project will demonstrate the feasibility of using atomic layer deposition (ALD) to apply ultrathin neutron-absorbing, corrosion-resistant layers consisting of ceramics, metals, or combinations thereof, on particles for enhanced nuclear fuel pellets. Current pellet coating technology utilizes chemical vapor deposition (CVD) in a fluidized bed reactor to deposit thick, porous layers of C (or PyC) and SiC. These graphitic/carbide materials degrade over time owing to fission product bombardment, active oxidation, thermal management issues, and long-term irradiation effects. ALD can be used to deposit potential ceramic barrier materials of interest, including ZrO{sub 2}, Y{sub 2}O{sub 3}:ZrO{sub 2} (YSZ), Al{sub 2}O{sub 3}, and TiO{sub 2}, or neutron-absorbing materials, namely B (in BN or B{sub 2}O{sub 3}) and Gd (in Gd{sub 2}O{sub 3}). This project consists of a two-pronged approach to integrate ALD into the next-generation nuclear plant (NGNP) fuel pellet manufacturing process:

  2. Microstructural studies of thermal spray coatings for biomedical applications

    Science.gov (United States)

    Sun, Limin

    2002-01-01

    /EMAA (ethylene methacrylic acid copolymer) coatings were produced using a flame spray system. The coatings exhibited increased Young's modulus compared to pure EMAA coatings and reasonable toughness and dissolution. The mechanical and dissolution behaviors were related to the volume and distribution of the HA in the polymer matrix. This technique provides a new means of preparing HA/polymer coatings for application as implants.

  3. Vacuum plasma spray coating

    Science.gov (United States)

    Holmes, Richard R.; Mckechnie, Timothy N.

    1989-01-01

    Currently, protective plasma spray coatings are applied to space shuttle main engine turbine blades of high-performance nickel alloys by an air plasma spray process. Originally, a ceramic coating of yttria-stabilized zirconia (ZrO2.12Y2O3) was applied for thermal protection, but was removed because of severe spalling. In vacuum plasma spray coating, plasma coatings of nickel-chromium-aluminum-yttrium (NiCrAlY) are applied in a reduced atmosphere of argon/helium. These enhanced coatings showed no spalling after 40 MSFC burner rig thermal shock cycles between 927 C (1700 F) and -253 C (-423 F), while current coatings spalled during 5 to 25 test cycles. Subsequently, a process was developed for applying a durable thermal barrier coating of ZrO2.8Y2O3 to the turbine blades of first-stage high-pressure fuel turbopumps utilizing the enhanced NiCrAlY bond-coating process. NiCrAlY bond coating is applied first, with ZrO2.8Y2O3 added sequentially in increasing amounts until a thermal barrier coating is obtained. The enchanced thermal barrier coating has successfully passed 40 burner rig thermal shock cycles.

  4. Anticorrosive coatings: a review

    DEFF Research Database (Denmark)

    Sørensen, Per Aggerholm; Kiil, Søren; Dam-Johansen, Kim

    2009-01-01

    The main objective of this review is to describe some of the important topics related to the use of marine and protective coatings for anticorrosive purposes. In this context, "protective" refers to coatings for containers, offshore constructions, wind turbines, storage tanks, bridges, rail cars......, and petrochemical plants while "marine" refers to coatings for ballast tanks, cargo holds and cargo tanks, decks, and engine rooms on ships. The review aims at providing a thorough picture of state-of-the-art in anticorrosive coatings systems. International and national legislation aiming at reducing the emission...... of volatile organic compounds (VOCs) have caused significant changes in the anticorrosive coating industry. The requirement for new VOC-compliant coating technologies means that coating manufacturers can no longer rely on the extensive track record of their time-served products to convince consumers...

  5. Evaluation of HVOF coatings

    Directory of Open Access Journals (Sweden)

    Mariana Landová

    2016-07-01

    Full Text Available Attention in this paper is devoted to the evaluation of wear coatings deposited using HVOF technology (high velocity oxy-fuel. There were evaluated three types of coatings based on WC-Co (next only 1343, WC-Co-Cr (next only 1350 and Cr3C2-25NiCr (next only 1375. There was assessed adherence of coatings, micro hardness, porosity and the tribological properties of erosive, abrasive, adhesive and wear resistance of coatings in terms of cyclic thermal load. Thanks to wide variety of suitable materials and their combinations, the area of utilization thermally sprayed coatings is very broad. It is possible to deposit coatings of various materials from pure metals to special alloys. The best results in the evaluated properties were achieved at the coating with the label 1375.

  6. Titanate nanotube coatings on biodegradable photopolymer scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Beke, S., E-mail: szabolcs.beke@iit.it [Department of Nanophysics, Istituto Italiano di Tecnologia, via Morego 30, 16163 Genova (Italy); Kőrösi, L. [Department of Biotechnology, Nanophage Therapy Center, Enviroinvest Corporation, Kertváros u. 2, H-7632, Pécs (Hungary); Scarpellini, A. [Department of Nanochemistry, Istituto Italiano di Tecnologia, via Morego 30, 16163 Genova (Italy); Anjum, F.; Brandi, F. [Department of Nanophysics, Istituto Italiano di Tecnologia, via Morego 30, 16163 Genova (Italy)

    2013-05-01

    Rigid, biodegradable photopolymer scaffolds were coated with titanate nanotubes (TNTs) by using a spin-coating method. TNTs were synthesized by a hydrothermal process at 150 °C under 4.7 bar ambient pressure. The biodegradable photopolymer scaffolds were produced by mask-assisted excimer laser photocuring at 308 nm. For scaffold coating, a stable ethanolic TNT sol was prepared by a simple colloid chemical route without the use of any binding compounds or additives. Scanning electron microscopy along with elemental analysis revealed that the scaffolds were homogenously coated by TNTs. The developed TNT coating can further improve the surface geometry of fabricated scaffolds, and therefore it can further increase the cell adhesion. Highlights: ► Biodegradable scaffolds were produced by mask-assisted UV laser photocuring. ► Titanate nanotube deposition was carried out without binding compounds or additives. ► The titanate nanotube coating can further improve the surface geometry of scaffolds. ► These reproducible platforms will be of high importance for biological applications.

  7. Hydroxyapatite coating on pretreated CoNiCrMo prosthesis

    Institute of Scientific and Technical Information of China (English)

    WANG Tao; A. Dorner-Reisel

    2005-01-01

    In order to improve the quality of the bio-active coating on medical grade CoNiCrMo substrate, hydroxyapatite(HA) coatings were produced via low-temperature dip-coating route on substrates treated using various surface pre-treating methods. The surface and cross-sectional morphologies of HA coatings were observed by SEM, as well as the bonding strength between coatings and substrates after different pre-treatments were characterized according to ASTM C633. The low-temperature HA dip-coating method with the substrate merely oxidized at 600℃ can provide a high quality HA coating for CoNiCrMo, of which the bonding strength reaches (58±5)MPa, higher than that of the clinically used HA coatings on Ti-alloys produced via plasma spray route, as well as a HA coating with full crystallinity and high phase-purity, which is more in-vivo stable than plasma sprayed HA coating.

  8. Using selective withdrawal to coat microparticles.

    Science.gov (United States)

    Cohen, I; Li, H; Hougland, J L; Mrksich, M; Nagel, S R

    2001-04-13

    We report a method that uses the process of selective withdrawal of one fluid through a second immiscible fluid to coat small particles with polymer films. Fluid is withdrawn through a tube with its orifice slightly above a water-oil interface. Upon increasing the flow rate, there is a transition from a state where only oil is withdrawn to a state where the water, containing the particles to be coated and appropriate prepolymer reagents, is entrained in a thin spout along with the oil. The entrained particles eventually cause the spout interface to break, producing a thin coat of controllable thickness around each particle, which can be subsequently polymerized using chemical reagents, light, or heat. This method allows flexibility in the chemical composition and thickness of the conformal coatings.

  9. Examining properties of arc sprayed nanostructured coatings

    Directory of Open Access Journals (Sweden)

    A. Czupryński

    2016-04-01

    Full Text Available The article presents the results of examining properties of arc sprayed coating obtained with nano-alloy on the iron matrix with a high amount of fine carbide precipitates sprayed on non-alloyed steel plates intended for high temperature operation. Powder metal cored wire EnDOtec DO*390N 1,6 mm diameter, was used to produce, dense, very high abrasion and erosion resistant coatings approx. 1,0 mm thick. Nano-material coatings characterization was done to determine abrasion resistance, erosion resistance, adhesion strength, hardness as well as metallographic examinations. Results have proved high properties of arc sprayed nano-material coatings and have shown promising industrial applications.

  10. Coatings Extend Life of Engines and Infrastructure

    Science.gov (United States)

    2010-01-01

    MesoCoat Inc., of Euclid, Ohio, collaborated with Glenn Research Center to provide thermal barrier coating (TBC) technology, developed by Glenn researcher Dongming Zhu, to enhance the lifespan and performance of engines in U.S. Air Force legacy aircraft. The TBC reduces thermal stresses on engine parts, increasing component life by 50 percent. MesoCoat is also producing metal cladding technology that may soon provide similar life-lengthening benefits for the Nation's infrastructure. Through a Space Act Agreement with Glenn, the company employs the Center's high-density infrared arc lamp system to bond its cladding materials for demonstration prototypes; the coating technology can prevent corrosion on metal beams, pipes, and rebar for up to 100 years.

  11. High efficiency turbine blade coatings.

    Energy Technology Data Exchange (ETDEWEB)

    Youchison, Dennis L.; Gallis, Michail A.

    2014-06-01

    The development of advanced thermal barrier coatings (TBCs) of yttria stabilized zirconia (YSZ) that exhibit lower thermal conductivity through better control of electron beam - physical vapor deposition (EB-PVD) processing is of prime interest to both the aerospace and power industries. This report summarizes the work performed under a two-year Lab-Directed Research and Development (LDRD) project (38664) to produce lower thermal conductivity, graded-layer thermal barrier coatings for turbine blades in an effort to increase the efficiency of high temperature gas turbines. This project was sponsored by the Nuclear Fuel Cycle Investment Area. Therefore, particular importance was given to the processing of the large blades required for industrial gas turbines proposed for use in the Brayton cycle of nuclear plants powered by high temperature gas-cooled reactors (HTGRs). During this modest (~1 full-time equivalent (FTE)) project, the processing technology was developed to create graded TBCs by coupling ion beam-assisted deposition (IBAD) with substrate pivoting in the alumina-YSZ system. The Electron Beam - 1200 kW (EB-1200) PVD system was used to deposit a variety of TBC coatings with micron layered microstructures and reduced thermal conductivity below 1.5 W/m.K. The use of IBAD produced fully stoichiometric coatings at a reduced substrate temperature of 600 oC and a reduced oxygen background pressure of 0.1 Pa. IBAD was also used to successfully demonstrate the transitioning of amorphous PVD-deposited alumina to the -phase alumina required as an oxygen diffusion barrier and for good adhesion to the substrate Ni2Al3 bondcoat. This process replaces the time consuming thermally grown oxide formation required before the YSZ deposition. In addition to the process technology, Direct Simulation Monte Carlo plume modeling and spectroscopic characterization of the PVD plumes were performed. The project consisted of five tasks. These included the production of layered

  12. High efficiency turbine blade coatings

    Energy Technology Data Exchange (ETDEWEB)

    Youchison, Dennis L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gallis, Michail A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-06-01

    The development of advanced thermal barrier coatings (TBCs) of yttria stabilized zirconia (YSZ) that exhibit lower thermal conductivity through better control of electron beam - physical vapor deposition (EB-PVD) processing is of prime interest to both the aerospace and power industries. This report summarizes the work performed under a two-year Lab-Directed Research and Development (LDRD) project (38664) to produce lower thermal conductivity, graded-layer thermal barrier coatings for turbine blades in an effort to increase the efficiency of high temperature gas turbines. This project was sponsored by the Nuclear Fuel Cycle Investment Area. Therefore, particular importance was given to the processing of the large blades required for industrial gas turbines proposed for use in the Brayton cycle of nuclear plants powered by high temperature gas-cooled reactors (HTGRs). During this modest (~1 full-time equivalent (FTE)) project, the processing technology was developed to create graded TBCs by coupling ion beam-assisted deposition (IBAD) with substrate pivoting in the alumina-YSZ system. The Electron Beam - 1200 kW (EB-1200) PVD system was used to deposit a variety of TBC coatings with micron layered microstructures and reduced thermal conductivity below 1.5 W/m.K. The use of IBAD produced fully stoichiometric coatings at a reduced substrate temperature of 600°C and a reduced oxygen background pressure of 0.1 Pa. IBAD was also used to successfully demonstrate the transitioning of amorphous PVD-deposited alumina to the -phase alumina required as an oxygen diffusion barrier and for good adhesion to the substrate Ni2Al3 bondcoat. This process replaces the time consuming thermally grown oxide formation required before the YSZ deposition. In addition to the process technology, Direct Simulation Monte Carlo plume modeling and spectroscopic characterization of the PVD plumes were performed. The project consisted of five tasks. These included the

  13. Controllable coating of microneedles for transdermal drug delivery.

    Science.gov (United States)

    Chen, Jianmin; Qiu, Yuqin; Zhang, Suohui; Yang, Guozhong; Gao, Yunhua

    2015-03-01

    Coated microneedles have been paid much attention recently, and several coating strategies have been developed to address the problems during coating process. However, there are still some unresolved issues, such as, precise control requirements, microneedle substrate contamination and high processing temperature. The purpose of this study was to develop a simple and controllable method to make uniform coatings on microneedles at room temperature. This novel method avoids the contamination of microneedle substrate by providing both the adsorption force of thickener and micro-scale coating film produced by a newly design device. Thickeners were screened to enhance the mass of coatings. The parameters that influence the coatings were tested systematically, which made coating process controllable. Finally, three model drugs were coated onto microneedles to prove the method is applicable more broadly. In addition, insertion experiments were carried out to test the drug delivery feasibility of the coated microneedles. In conclusion, this study presents a simple and controllable method to coat microneedles with small molecular chemical drugs or large proteins for rapid skin drug delivery.

  14. Evolution of the Automotive Body Coating Process—A Review

    Directory of Open Access Journals (Sweden)

    Nelson K. Akafuah

    2016-06-01

    Full Text Available Automotive coatings and the processes used to coat automobile surfaces exemplify the avant-garde of technologies that are capable of producing durable surfaces, exceeding customers’ expectations of appearance, maximizing efficiency, and meeting environmental regulations. These accomplishments are rooted in 100 years of experience, trial-and-error approaches, technique and technology advancements, and theoretical assessments. Because of advancements directed at understanding the how, why, when, and where of automobile coatings, the progress in controlling droplets and their deposition attributes, and the development of new technologies and paint chemistries, a comprehensive and up-to-date review of automobile coatings and coating technologies was considered to be of value to industrial practitioners and researchers. Overall, the critical performance factors driving the development and use of advanced automotive coatings and coating technologies are (a aesthetic characteristics; (b corrosion protection; (c mass production; (d cost and environmental requirements; and (e appearance and durability. Although the relative importance of each of these factors is debatable, the perfection of any one at the expense of another would be unacceptable. Hence, new developments in automotive coatings are described and discussed in the following review, and then related to improvements in production technologies and paints. Modern automotive coating procedures are also discussed in detail. Finally, an extrapolation into the future of automotive coating is offered with a view of the developments and technologies needed for an increasingly efficient and more sustainable coatings industry.

  15. Healing particles in self-healing thermal barrier coatings

    NARCIS (Netherlands)

    Derelioglu, Z.; Anusuya Ponnusami, S.; Turteltaub, S.; Van der Zwaag, S.; Sloof, W.G.

    2013-01-01

    Crack healing in ceramic thermal barrier coatings (TBCs) may be realized by embedding Mo-Si based particles in the thermal barrier coating. Upon cracking, these particles are exposed to oxygen that permeates through the top layer and the crack gap is filled with SiO2 which is produced from oxidation

  16. Enhancing thermal barrier coatings performance through reinforcement of ceramic topcoat

    Science.gov (United States)

    Bogdanovich, V. I.; Giorbelidze, M. G.

    2016-11-01

    This paper studies structure of thermal barrier coatings applied to hot gas path components in gas turbine engines and produced in a number of ways, and its impact on performance. Methods of structural reinforcement for ceramic topcoat in thermal barrier coatings are considered.

  17. Cellulose nanofibers use in coated paper

    Science.gov (United States)

    Richmond, Finley

    Cellulose Nanofibers (CNF) are materials that can be obtained by the mechanical breakdown of natural fibers. CNF have the potential to be produced at low cost in a paper mill and may provide novel properties to paper, paper coatings, paints, or other products. However, suspensions have a complex rheology even at low solid contents. To be able to coat, pump, or mix CNF at moderate solids, it is critical to understand the rheology of these suspensions and how they flow in process equipment; current papers only report the rheology up to 6% solids. Few publications are available that describe the coating of CNF onto paper or the use of CNF as an additive into a paper coating. The rheology of CNF suspensions and coatings that contain CNF were characterized with parallel-disk geometry in a controlled stress rheometer. The steady shear viscosity, the complex viscosity, the storage modulus, and the yield stress were determined for the range of solids or concentrations (2.5-10.5%). CNF were coated onto paper with a laboratory rod coater, a size press and a high speed cylindrical laboratory coater (CLC). For each case, the coat weights were measures and the properties of the papers were characterized. CNF water base suspension was found to be a shear thinning with a power law index of around 0.1. Oscillatory tests showed a linear viscoelastic region at low strains and significant storage and loss moduli even at low solids. The Cox Merz rule does not hold for CNF suspensions or coating formulations that contain CNF with complex viscosities that are about 100 times larger than the steady shear viscosities. Paper coating formulations that contain CNF were found to have viscosities and storage and loss moduli that are over ten times larger than coatings that contain starch at similar solids. CNF suspensions were coated on papers with low amount transferred on paper either at high solids or high nip loadings. The amount transferred appears to be controlled by an interaction of

  18. Electrospark deposition coatings

    Science.gov (United States)

    Sheely, W. F.

    1986-11-01

    Hard surfacing for wear resistant and low-friction coatings has been improved by means of advances in the computer controls in electronic circuitry of the electrospark deposition (ESD) process. coatings of nearly any electrically conductive metal alloy or cermet can be deposited on conductive materials. Thickness is usually two mils or less, but can be as high as 10 mils. ESD coatings can quadrupole cutting tool life.

  19. Advanced Multifunctional Coating

    Science.gov (United States)

    2011-08-17

    and UV durability of then current chrome free TT-P-2756 SPTC • Leverage APC technology into SPTC • Coating uses same fluoropolyurethane technology...as APC currently used on C-17 • Leverage recent advances in chrome free corrosion inhibitor technology • State of the art chrome free corrosion...coat exposed metal Aluminum Base Metal Original Finish System Aged APC Topcoat Conversion Coat Chromic Acid Anodize Aluminum Cladding Original Primer

  20. Oxide coating development

    Energy Technology Data Exchange (ETDEWEB)

    Stinton, D.P.

    1995-06-01

    Monolithic SiC heat exchangers and fiber-reinforced SiC-matrix composite heat exchangers and filters are susceptible to corrosion by alkali metals at elevated temperatures. Protective coatings are currently being developed to isolate the SiC materials from the corrodants. Unfortunately, these coatings typically crack and spall when applied to SiC substrates. The purpose of this task is to determine the feasibility of using a compliant material between the protective coating and the substrate. The low-modulus compliant layer could absorb stresses and eliminate cracking and spalling of the protective coatings.

  1. Superhard Nanocomposite Coatings

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The recent development in the field of nanocomposite coatings with good mechanical properties is critically reviewed in this paper. The design principle and materials selection for the nanocomposite coatings are introduced. Different methods for the preparation of superhard nanocomposite coatings are described with emphasis on the magnetron sputtering. Based on recent theoretical and experimental results regarding the appearance of superhardness in nanocomposite coating, lattice parameter changes, crystallite size, microstructure and morphology are reviewed in detail. Also emphasized are the mechanical properties (especially on hardness) and the ways by which the properties are derived.

  2. Final Project Report G-Plus Windshield Coatings

    Energy Technology Data Exchange (ETDEWEB)

    Matson, Dean W.; Koram, Kwaku

    2002-08-01

    Samples of Sungate windshield material provided by PPG were analyzed to ascertain failure mechanisms observed at the interface between a copper busbar and the electrically conductive coating in use. Samples of “failed” windshield material were characterized using optical and electron microscopy, as well as surface analysis methods. These were compared to corresponding samples of “good” coatings. The primary failure mechanism of the coated windshield appears to be related to electrical discharges that originate where air-filled gaps are present between the copper busbar and the conductive coating. Gaps are produced by irregularities or wrinkles in the copper busbar that may result from the installation process.

  3. Self-assembled nanolaminate coatings (SV)

    Energy Technology Data Exchange (ETDEWEB)

    Fan, H.

    2012-03-01

    Sandia National Laboratories (Sandia) and Lockheed Martin Aeronautics (LM Aero) are collaborating to develop affordable, self-assembled, nanocomposite coatings and associated fabrication processes that will be tailored to Lockheed Martin product requirements. The purpose of this project is to develop a family of self-assembled coatings with properties tailored to specific performance requirements, such as antireflective (AR) optics, using Sandia-developed self-assembled techniques. The project met its objectives by development of a simple and economic self-assembly processes to fabricate multifunctional coatings. Specifically, materials, functionalization methods, and associated coating processes for single layer and multiple layers coatings have been developed to accomplish high reflective coatings, hydrophobic coatings, and anti-reflective coatings. Associated modeling and simulations have been developed to guide the coating designs for optimum optical performance. The accomplishments result in significant advantages of reduced costs, increased manufacturing freedom/producibility, improved logistics, and the incorporation of new technology solutions not possible with conventional technologies. These self-assembled coatings with tailored properties will significantly address LMC's needs and give LMC a significant competitive lead in new engineered materials. This work complements SNL's LDRD and BES programs aimed at developing multifunctional nanomaterials for microelectronics and optics as well as structure/property investigations of self-assembled nanomaterials. In addition, this project will provide SNL with new opportunities to develop and apply self-assembled nanocomposite optical coatings for use in the wavelength ranges of 3-5 and 8-12 micrometers, ranges of vital importance to military-based sensors and weapons. The SANC technologies will be applied to multiple programs within the LM Company including the F-35, F-22, ADP (Future Strike Bomber

  4. Ion sequestration particles for naval anticorrosion coatings

    Science.gov (United States)

    Zguris, Zachary Z.

    Corrosion is the electrochemical process of a metal returning to its lower energy state, the metal oxide. The cost of corrosion is difficult to estimate. One area particularly susceptible to corrosion problems with high maintenance costs is that of the 20,000 tanks existent in the US Naval Fleet. The Navy is sponsoring the development of novel coatings and additives that can be used to decrease the rising corrosion related costs. This dissertation describes in detail the synthesis of Ion Sequestration Particles (ISP) that when added to the standard MIL-DTL-24441 or potentially another coating system act to enhance the anticorrosion properties of the coating. A solid ion sequestration core material (SISCM) is first produced. The core is then encapsulated in a second stage forming a shell that protects the SISCM sufficiently from the harmful interactions with uncured epoxy based coatings. ISPs were designed to sequester harmful ions while releasing passivating ions in their place. The passivating ions then migrate to defect sites at the coating interface where they act to inhibit corrosion. The anticorrosion performance of ISPs in epoxy coatings has been demonstrated by both 500 hrs of hot deionized water immersion and 1000 hrs of salt spray exposure (ASTM B117). The best improvements in coating performance are attained with ISP content ranging from 5-10 wt % loading in a coating. ISPs were designed to limit the transport of harmful ions through the coating. However this work has determined high diffusion coefficients for ions (CI- and PO42-) through the epoxy matrix. Without ISPs, the diffusion coefficient through the MIL-DTL-24441 coating was determined for phosphate to be 1.16x10-7 cm2/s and for chloride to be in the range of 2.7x10-9 to 5.6x10-10 cm2/s. The addition of 5 wt % ISPs to the coating had the effect of decreasing the diffusion coefficient by an average of 25.5%. These results yield the conclusion that the enhanced anticorrosion properties of coatings

  5. Fabrication of nanogradient coatings for laser devices using the method of magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Abramov, N F; Volpyan, O D; Obod, Yu A [Open Joint-Stock Company M.F. Stel' makh Polyus Research Institute, Moscow (Russian Federation); Dronskii, R V [' Fotron-Auto' Scientific Manufacture Enterprise, Moscow (Russian Federation)

    2013-09-30

    Significant advantages of the magnetron sputtering method for producing complex high-quality optical coatings for laser devices are shown. Technology aspects of efficient fabrication of such coatings are considered. The capabilities of the developed automated technological and control equipment are described. (nanogradient dielectric coatings and metamaterials)

  6. Material-Process-Performance Relationships for Roll-to-Roll Coated PEM Electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Mauger, Scott; Neyerlin, K.C.; Stickel, Jonathan; Ulsh, Michael; More, Karren; Wood, David

    2017-04-26

    Roll-to-roll (R2R) coating is the most economical and highest throughput method for producing fuel cell electrodes. R2R coating encompasses many different methodologies to create uniform films on a moving web substrate. Here we explore two coating methods, gravure and slot die, to understand the impacts of each on film uniformity and performance.

  7. CrCuAgN PVD nanocomposite coatings: Effects of annealing on coating morphology and nanostructure

    Science.gov (United States)

    Liu, Xingguang; Iamvasant, Chanon; Liu, Chang; Matthews, Allan; Leyland, Adrian

    2017-01-01

    CrCuAgN PVD nanocomposite coatings were produced using pulsed DC unbalanced magnetron sputtering. This investigation focuses on the effects of post-coat annealing on the surface morphology, phase composition and nanostructure of such coatings. In coatings with nitrogen contents up to 16 at.%, chromium exists as metallic Cr with N in supersaturated solid solution, even after 300 °C and 500 °C post-coat annealing. Annealing at 300 °C did not obviously change the phase composition of both nitrogen-free and nitrogen-containing coatings; however, 500 °C annealing resulted in significant transformation of the nitrogen-containing coatings. The formation of Ag aggregates relates to the (Cu + Ag)/Cr atomic ratio (threshold around 0.2), whereas the formation of Cu aggregates relates to the (Cu + Ag + N)/Cr atomic ratio (threshold around 0.5). The primary annealing-induced changes were reduced solubility of Cu, Ag and N in Cr, and the composition altering from a mixed ultra-fine nanocrystalline and partly amorphous phase constitution to a coarser, but still largely nanocrystalline structure. It was also found that, with sufficient Cu content (>12 at.%), annealing at a moderately high temperature (e.g. 500 °C) leads to transportation of both Cu and Ag (even at relatively low concentrations of Ag, ≤3 at.%) from inside the coating to the coating surface, which resulted in significant reductions in friction coefficient, by over 50% compared to that of the substrate (from 0.31 to 0.14 with a hemispherical diamond indenter, and from 0.83 to 0.40 with an alumina ball counterface, respectively). Results indicate that the addition of both Cu and Ag (in appropriate concentrations) to nitrogen-containing chromium is a viable strategy for the development of 'self-replenishing' silver-containing thin film architectures for temperature-dependent solid lubrication requirements or antimicrobial coating applications.

  8. Survey of coatings for solar collectors

    Science.gov (United States)

    Mcdonald, G. E.

    1975-01-01

    Optimum solar selective properties of black chrome require some tailoring of current and time for plating solution being used. Black zinc is produced from high zinc electroplate by subsequent conversion with chromate dip. Measurements have also been made of reflectance of previously known solar selective coatings of black copper and electroplated black nickel.

  9. Corrosion protective coating for metallic materials

    Science.gov (United States)

    Buchheit, Rudolph G.; Martinez, Michael A.

    1998-01-01

    Corrosion protective coatings for metallic materials, particularly aluminum and aluminum alloys, produced with simple, low-cost equipment and materials other than toxic metals or metal salts, or metal cyanides. The metallic material is cleaned, degreased, and deoxidized, the surface is converted to a substantially alkaline condition, and the surface is chemically sealed with inorganic metal compounds.

  10. Computational homogenisation for thermoviscoplasticity: application to thermally sprayed coatings

    Science.gov (United States)

    Berthelsen, Rolf; Denzer, Ralf; Oppermann, Philip; Menzel, Andreas

    2017-07-01

    Metal forming processes require wear-resistant tool surfaces in order to ensure a long life cycle of the expensive tools together with a constant high quality of the produced components. Thermal spraying is a relatively widely applied coating technique for the deposit of wear protection coatings. During these coating processes, heterogeneous coatings are deployed at high temperatures followed by quenching where residual stresses occur which strongly influence the performance of the coated tools. The objective of this article is to discuss and apply a thermo-mechanically coupled simulation framework which captures the heterogeneity of the deposited coating material. Therefore, a two-scale finite element framework for the solution of nonlinear thermo-mechanically coupled problems is elaborated and applied to the simulation of thermoviscoplastic material behaviour including nonlinear thermal softening in a geometrically linearised setting. The finite element framework and material model is demonstrated by means of numerical examples.

  11. Optically transparent, scratch-resistant, diamond-like carbon coatings

    Science.gov (United States)

    He, Xiao-Ming; Lee, Deok-Hyung; Nastasi, Michael A.; Walter, Kevin C.; Tuszewski, Michel G.

    2003-06-03

    A plasma-based method for the deposition of diamond-like carbon (DLC) coatings is described. The process uses a radio-frequency inductively coupled discharge to generate a plasma at relatively low gas pressures. The deposition process is environmentally friendly and scaleable to large areas, and components that have geometrically complicated surfaces can be processed. The method has been used to deposit adherent 100-400 nm thick DLC coatings on metals, glass, and polymers. These coatings are between three and four times harder than steel and are therefore scratch resistant, and transparent to visible light. Boron and silicon doping of the DLC coatings have produced coatings having improved optical properties and lower coating stress levels, but with slightly lower hardness.

  12. Porous Structure Characterization in Titanium Coating for Surgical Implants

    Directory of Open Access Journals (Sweden)

    M.V. Oliveira

    2002-09-01

    Full Text Available Powder metallurgy techniques have been used to produce controlled porous structures, such as the porous coatings applied for dental and orthopedic surgical implants, which allow bony tissue ingrowth within the implant surface improving fixation. This work presents the processing and characterization of titanium porous coatings of different porosity levels, processed through powder metallurgy techniques. Pure titanium sponge powders were used for coating and Ti-6Al7Nb powder metallurgy rods were used as substrates. Characterization was made through quantitative metallographic image analysis using optical light microscope for coating porosity data and SEM analysis for evaluation of the coating/substrate interface integrity. The results allowed optimization of the processing parameters in order to obtain porous coatings that meet the requirements for use as implants.

  13. Carbon nanotube and graphene nanoribbon-coated conductive Kevlar fibers.

    Science.gov (United States)

    Xiang, Changsheng; Lu, Wei; Zhu, Yu; Sun, Zhengzong; Yan, Zheng; Hwang, Chi-Chau; Tour, James M

    2012-01-01

    Conductive carbon material-coated Kevlar fibers were fabricated through layer-by-layer spray coating. Polyurethane was used as the interlayer between the Kevlar fiber and carbon materials to bind the carbon materials to the Kevlar fiber. Strongly adhering single-walled carbon nanotube coatings yielded a durable conductivity of 65 S/cm without significant mechanical degradation. In addition, the properties remained stable after bending or water washing cycles. The coated fibers were analyzed using scanning electron microcopy and a knot test. The as-produced fiber had a knot efficiency of 23%, which is more than four times higher than that of carbon fibers. The spray-coating of graphene nanoribbons onto Kevlar fibers was also investigated. These flexible coated-Kevlar fibers have the potential to be used for conductive wires in wearable electronics and battery-heated armors.

  14. Stronger multilayer acrylic dielectric elastomer actuators with silicone gel coatings

    Science.gov (United States)

    Lau, Gih-Keong; La, Thanh-Giang; Sheng-Wei Foong, Ervin; Shrestha, Milan

    2016-12-01

    Multilayer dielectric elastomer actuators (DEA) perform worst off than single-layer DEAs due to higher susceptibility to electro-thermal breakdown. This paper presents a hot-spot model to predict the electro-thermal breakdown field of DEAs and its dependence on thermal insulation. To inhibit the electrothermal breakdown, silicone gel coating was applied as barrier coating to multilayer acrylic DEA. The gel coating helps suppress the electro-thermally induced puncturing of DEA membrane at the hot spot. As a result, the gel-coated DEAs, in either a single layer or a multilayer stack, can produce 30% more isometric stress change as compared to those none-coated. These gel-coated acrylic DEAs show great potential to make stronger artificial muscles.

  15. Measurement of Thermal Noise in Multilayer Coatings with Optimized Layer Thickness

    CERN Document Server

    Villar, Akira E; DeSalvo, Riccardo; Libbrecht, Kenneth G; Michel, Christophe; Morgado, Nazario; Pinard, Laurent; Pinto, Innocenzo M; Pierro, Vincenzo; Galdi, Vincenzo; Principe, Maria; Taurasi, Ilaria

    2010-01-01

    A standard quarter-wavelength multilayer optical coating will produce the highest reflectivity for a given number of coating layers, but in general it will not yield the lowest thermal noise for a prescribed reflectivity. Coatings with the layer thicknesses optimized to minimize thermal noise could be useful in future generation interferometric gravitational wave detectors where coating thermal noise is expected to limit the sensitivity of the instrument. We present the results of direct measurements of the thermal noise of a standard quarter-wavelength coating and a low noise optimized coating. The measurements indicate a reduction in thermal noise in line with modeling predictions.

  16. Novel surface coating materials for endodontic dental implant

    Energy Technology Data Exchange (ETDEWEB)

    Fathi, M.H. [Isfahan Univ. of Technology, Materials Engineering Dept., Isfahan (Iran, Islamic Republic of); Mortazavi, V.; Moosavi, S.B. [Isfahan Univ. of Medical Sciences, Faculty of Dentistry, Isfahan (Iran, Islamic Republic of)

    2003-07-01

    The aim of this study was to design and produce novel coating materials in order to obtain two goals including; improvement of the corrosion behavior of metallic dental endodontic implant and the bone osteointegration simultaneously. Stainless steel 316L (SS) was used as a metallic substrate and a novel Hydroxyapatite/Titanium (HA/Ti) composite coating was prepared on it. Structural characterization techniques including XRD, SEM and EDX were utilized to investigate the microstructure and morphology of the coating. Electrochemical tests were performed in physiological solutions in order to determine and compare the corrosion behavior of the coated and uncoated specimens as an indication of biocompatibility. Two types of endodontic implants including; SS with and without (HA/Ti) composite coating were prepared and subsequently implanted in the mandibular canine of 20 cats after completion of root canal treatment and osseous preparation. After a healing period of 4 months, osteointegration evaluation and histopathological interpretation was carried out using SEM and optical microscopy. Results indicate that the novel HA/Ti composite coating improves the corrosion behavior and biocompatibility of SS endodontic dental implant. The clinical evaluation (in vivo test) results showed that there was significant difference in osteointegration between coated and uncoated endodontic dental implants and average bone osteointegration of coated implants were more than uncoated implants. The histopathological results and bone tissue response to the coated implants was acceptable and it was concluded that HA/Ti composite coated SS could be used as well as an endodontic dental implant. (author)

  17. A coated electrode carrier for cochlear implantation reduces insertion forces.

    Science.gov (United States)

    Radeloff, Andreas; Unkelbach, Marc H; Mack, Martin G; Settevendemie, Claudia; Helbig, Silke; Mueller, Joachim; Hagen, Rudolf; Mlynski, Robert

    2009-05-01

    To assess the insertion forces and feasibility of insertion of a prototype electrode carrier coated with a flexible and biodegradable coating developed for lubrication and drug delivery. Experimental study. Eight coated and eight uncoated electrode carriers were inserted into a scala tympani model by means of an insertion device, and forces produced during insertion were determined in near real time. The maximum insertion depths and insertion angle were determined. To test the handling and operability, five coated electrode carriers were implanted into human temporal bones. Additionally, the bones were processed undecalcified and the distribution of the coating material within the cochlea evaluated. Insertion forces were markedly reduced in the group of coated electrode carriers for insertion depths above 15 mm. The insertions were less fitful and led to a higher maximum insertion angle. The insertion of the coated electrode carrier was feasible, and the coating material was evident up to the apical parts of the cochlea postimplantation. Coating of a cochlear implant electrode carrier may reduce insertion forces responsible for the surgical trauma. Loaded with active substances, the coating may help to deliver drugs to the apical parts of the cochlear where hair cells reside in patients with residual hearing.

  18. MECHANICAL PERFORMANCE OF METAL-CERAMIC INTERFACES PRODUCED BY LASER PROCESSING

    NARCIS (Netherlands)

    van den Burg, M.; de Hosson, J.T.M.

    1995-01-01

    This paper concentrates on the mechanical performance of various ceramic coatings of Cr2O3 on Steel (SAF2205), as produced by CO2 laser processing. The thickness of the coating that can be applied by laser coating is limited to about 200 mu m setting a limit to the maximum strain energy release rate

  19. MECHANICAL PERFORMANCE OF METAL-CERAMIC INTERFACES PRODUCED BY LASER PROCESSING

    NARCIS (Netherlands)

    van den Burg, M.; de Hosson, J.T.M.

    1995-01-01

    This paper concentrates on the mechanical performance of various ceramic coatings of Cr2O3 on Steel (SAF2205), as produced by CO2 laser processing. The thickness of the coating that can be applied by laser coating is limited to about 200 mu m setting a limit to the maximum strain energy release rate

  20. Wear behavior of gas tunnel type plasma sprayed Zr-based metallic glass composite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Yugeswaran, S., E-mail: yugeswaran@gmail.com [Joining and Welding Research Institute, Osaka University, 11-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Kobayashi, A., E-mail: kobayasi@jwri.osaka-u.ac.jp [Joining and Welding Research Institute, Osaka University, 11-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Suresh, K., E-mail: ksureshphy@gmail.com [Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region (China); Rao, K.P., E-mail: mekprao@cityu.edu.hk [Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region (China); Subramanian, B., E-mail: subramanianb3@gmail.com [CSIR - Central Electrochemical Research Institute, Karaikudi 630 006 (India)

    2012-09-01

    Highlights: Black-Right-Pointing-Pointer Zr-based metallic glass composite coatings are prepared by gas tunnel plasma torch. Black-Right-Pointing-Pointer Increasing plasma current increases crystallinity amount and hardness of coatings. Black-Right-Pointing-Pointer Coating produced at 300 A plasma current gives minimum sliding wear rate. Black-Right-Pointing-Pointer Coating produced at higher plasma current gives lower erosive wear rate. - Abstract: Gas tunnel type plasma spraying is a prospective method to produce metallic glass composite coatings with high quality due to its noteworthy feature of process controllability. In this study, Zr{sub 55}Cu{sub 30}Al{sub 10}Ni{sub 5} metallic glass composite coatings were produced by gas tunnel type plasma spraying torch under optimum spraying conditions with selected plasma currents. The formation mechanism, sliding, and erosive wear behaviors of the coatings with respect to plasma current was examined. The phase and thermal analyses as well as microstructure of the plasma sprayed coatings produced at different plasma currents were characterized using X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX) techniques. The sliding and erosive wear behaviors of the coatings were studied using a pin-on-disc and a specially designed erosive wear tester, respectively. The results showed that an increase in plasma current increased the crystalline content in the metallic glass composite coatings, which enhanced the hardness and wear resistance of the coatings.

  1. UNBALANCED MAGNETRON SPUTTERING SYSTEM FOR PRODUCING CORROSION RESISTANCE MULTILAYER COATINGS

    Directory of Open Access Journals (Sweden)

    DIANA MARULANDA

    2012-01-01

    Full Text Available En este trabajo se describe un sistema de sputtering con magnetrón desbalanceado que permite producir recubrimientos en multicapa resistentes a la corrosión. La principal ventaja de este sistema es que combina características tales como una disposición multi-cátodo, control de temperatura, control sobre la rotación del portamuestras y capacidad de intercambiar muestras sin romper el vacío. El desempeño del sistema se verificó a través de la producción de multicapas nanométricas de Cr/CrN sobre acero inoxidable 304 y silicio (100 y la evaluación de su resistencia a la corrosión. Se utilizó difracción de rayos X (DRX pare estudiar la microestructura cristalina, y microscopía electrónica de barrido (MEB para caracterizar la formación de la multicapa. Los resultados de DRX muestran las orientaciones (111 y (200 para las multicapas de CrN y los resultados de MEB muestran claramente la formación de una estructura en multicapa. La resistencia a la corrosión se evaluó a través de estudios electroquímicos y los resultados muestran que la multicapa de Cr/CrN presenta menor corriente de corrosión y un potencial de corrosión más alto en comparación al sustrato de acero inoxidable 304.

  2. Monitoring the electrochemical potential noise produced by coated metal electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Metikos-Hukovic, M. (Zagreb Univ. (Yugoslavia). Inst. of Electrochemistry); Loncar, M. (Institute of Metallurgy, Sisak (Yugoslavia)); Zevnik, C. (Iskra-Kibernetika, Kranj (Yugoslavia))

    1989-08-01

    The protective properties of paints with polyvinyl phenol formaldehyde and cumar resin bases were tested on mild steel using electrochemical noise measurements. Amplitude spectra of low frequency electrochemical potential noise demonstrated a correlation between the rate and form of the corrosion potential. Such results suggest a practical nondestructive electrochemical corrosion monitoring technique for detecting general corrosion and pitting. The corrosion products were subjected to X-ray diffraction analysis and electron-probe microanalysis. (orig.).

  3. Durability of hydrophobic coatings for superhydrophobic aluminum oxide

    Science.gov (United States)

    Jenner, Elliot; Barbier, Charlotte; D'Urso, Brian

    2013-10-01

    Robust and easily produced superhydrophobic surfaces are of great interest for mechanical applications, including drag reduction and MEMS. We produce novel superhydrophobic surfaces with several different coatings and tested the durability of each of these coatings with respect to long term immersion in water in order to determine the most long-lasting surface preparation. A pair of combinations of spin on polymers, surface features, and adhesion promoters was found that provide long term durability.

  4. Mechanically Invisible Polymer Coatings

    DEFF Research Database (Denmark)

    2014-01-01

    phase comprises particles, said particles comprising a filler material and an encapsulating coating of a second polymeric material, wherein the backbones of the first and second polymeric materials are the same. The composition may be used in electroactive polymers (EAPs) in order to obtain mechanically...... invisible polymer coatings....

  5. Chinese Decorative Coatings Market

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Growth prospects The Chinese market for decorative coatings, excluding non-architectural products such as industrial varnishes,marine paint and other industrially applied coatings, has been growing byaround 10% annually and was estimated to be worth Eurol.3 billion a year, with an annual per capita consumption of just less than 1 liter ofpaint.

  6. Rock-hard coatings

    NARCIS (Netherlands)

    Muller, M.

    2007-01-01

    Aircraft jet engines have to be able to withstand infernal conditions. Extreme heat and bitter cold tax coatings to the limit. Materials expert Dr Ir. Wim Sloof fits atoms together to develop rock-hard coatings. The latest invention in this field is known as ceramic matrix composites. Sloof has sign

  7. Coating of graphene

    NARCIS (Netherlands)

    Schneider, G.F.; Dekker, C.

    2014-01-01

    The present invention is in the field of highly crystalline graphene and coating said graphene with a layer. Said graphene may have further structures, such as nanopores, nanogaps, and nanoribbons. The coated graphene can be used for biomolecular analysis and modification, such as DNA-sequencing, as

  8. Unobtrusive graphene coatings

    NARCIS (Netherlands)

    Mugele, Friedrich Gunther

    2012-01-01

    The contact angle of water drops on substrates for which the wettability is dominated by van der Waals forces remains unchanged when the substrates are coated with a monolayer of graphene. Such 'wetting transparency' could lead to superior conducting and hydrophobic graphene-coated surfaces with tun

  9. Coated electroactive materials

    Energy Technology Data Exchange (ETDEWEB)

    Amine, Khalil; Abouimrane, Ali

    2016-08-30

    A process includes suspending an electroactive material in a solvent, suspending or dissolving a carbon precursor in the solvent; and depositing the carbon precursor on the electroactive material to form a carbon-coated electroactive material. Compositions include a graphene-coated electroactive material prepared from a solution phase mixture or suspension of an electroactive material and graphene, graphene oxide, or a mixture thereof.

  10. Coating of graphene

    NARCIS (Netherlands)

    Schneider, G.F.; Dekker, C.

    2014-01-01

    The present invention is in the field of highly crystalline graphene and coating said graphene with a layer. Said graphene may have further structures, such as nanopores, nanogaps, and nanoribbons. The coated graphene can be used for biomolecular analysis and modification, such as DNA-sequencing, as

  11. Nanostructured Protective Coatings

    Science.gov (United States)

    2006-01-01

    stresses induce strain fatigue with subsequent formation of cracks. Cracking in coatings leads to materials failure observed physically as spallation or...elevated temperatures. In this test a hole is drilled into the substrate before coating it. This allows a fixed amount of air to be trapped at the

  12. Deposition of wear-resistant steel surfaces by the plasma rotating electrode coating process

    Science.gov (United States)

    Kim, Michael Robert

    A high-deposition rate thermal spray method was investigated for the purpose of coating aluminum cylinder bores with a wear resistant surface. This method, the plasma rotating electrode coating system (PROTEC) utilized transferred-arc melting of a rapidly rotating consumable electrode to create a droplet stream via centrifugal atomization. A cylindrical substrate was placed around the rotating rod, in the flight path of the droplets, to deposit a coating onto the internal surface of the cylinder. Selected coatings of 1045 steel deposited by the PROTEC coating method exhibited lower wear loss in lubricated sliding than wire-arc sprayed carbon steel coatings and gray cast iron. Splat cohesion was shown to be a significant factor in the wear resistance of PROTEC coatings. The relationship between deposition enthalpy and cooling rate of the coating was found to have the greatest effect on coating microstructure, and the coating cohesion. The most rapidly solidified coatings showed inferior splat cohesion in comparison to coatings that cooled more slowly. The increase in splat cohesion with decreased cooling rate was accompanied by the formation of a directionally oriented coating microstructure, likely formed during cellular solidification of the coating. A model describing the thermal state of the deposition process was used to predict the deposition conditions that would result in a cellular structure, and the level of splat cohesion required to produce a wear resistant coating.

  13. Functionally graded materials produced by laser cladding

    NARCIS (Netherlands)

    Pei, Y.T.; Hosson, J.Th.M. De

    2000-01-01

    AlSi40 functionally graded materials (FGMs) were produced by a one-step laser cladding process on cast Al-alloy substrate as a possible solution for interfacial problems often present in laser coatings. The microstructure of the FGMs consists of a large amount of silicon primary particles surrounded

  14. Functionally graded materials produced by laser cladding

    NARCIS (Netherlands)

    Pei, Y.T.; Hosson, J.Th.M. De

    2000-01-01

    AlSi40 functionally graded materials (FGMs) were produced by a one-step laser cladding process on cast Al-alloy substrate as a possible solution for interfacial problems often present in laser coatings. The microstructure of the FGMs consists of a large amount of silicon primary particles surrounded

  15. Functionally Graded Materials Produced by Laser Cladding

    NARCIS (Netherlands)

    Pei, Y.T.; Hosson, J.Th.M. De

    2000-01-01

    AlSi40 functionally graded materials (FGMs) were produced by a one-step laser cladding process on cast Al-alloy substrate as a possible solution for interfacial problems often present in laser coatings. The microstructure of the FGMs consists of a large amount of silicon primary particles surrounded

  16. Methods of producing continuous boron carbide fibers

    Energy Technology Data Exchange (ETDEWEB)

    Garnier, John E.; Griffith, George W.

    2015-12-01

    Methods of producing continuous boron carbide fibers. The method comprises reacting a continuous carbon fiber material and a boron oxide gas within a temperature range of from approximately 1400.degree. C. to approximately 2200.degree. C. Continuous boron carbide fibers, continuous fibers comprising boron carbide, and articles including at least a boron carbide coating are also disclosed.

  17. Anti-friction Coating for Drilling of Green Austempered Ductile Iron (ADI) grade

    Science.gov (United States)

    Meena, A.; El Mansori, M.; Ghidossi, P.; Mkaddem, A.

    2011-05-01

    In this paper the anti-friction performance of two types of coating, post-coated coating and PVD-TiAlN coating were investigated when drilling green austempered ductile iron (ADI) grade. The green ADI grade is produced by a new processing technology known as continuous casting-heat treatment process. The effect of coatings on tool wear and surface finish of the holes when drilling using coolant were reported. Results showed that the tool with post-coated coating has higher anti-friction properties as compared to PVD-TiAlN coating in terms of tool wear and surface roughness. Results also showed that there is a formation of preventive aluminum oxide layer during machining for both types of coating.

  18. CORROSION BEHAVIOR OF A CONVERSION COATING BASED ON ZIRCONIUM AND COLORANTS ON GALVANIZED STEEL BY ELECTRODEPOSITION

    Directory of Open Access Journals (Sweden)

    Josiane Soares Costa

    2015-06-01

    Full Text Available Corrosion performance of Zr-based coating on substrates obtained by zinc electrodeposition in an alkaline bath is compared to chromate coatings (Cr III and Cr VI. The “nano Zr” is a conversion coating formed by immersion in a hexafluorozirconic acid solution. Since the “nano Zr” coating is transparent, the addiction of a colorant provides color to the surface. In this case, the colorant, when applied after the conversion coating, conferred the yellow color to the surface. The coating produced improves the corrosion protection of the substrate. For this study the samples were analyzed by electrochemical impedance spectroscopy (EIS and accelerated corrosion test in a humidity chamber. The results showed similar behaviors between the “nano Zr”, colorant and the chromate (Cr III coating. Therefore this kind of conversion coating is a promising substitute for chromate coatings.

  19. Maximum shields: the assembly and function of the bacterial spore coat.

    Science.gov (United States)

    Driks, Adam

    2002-06-01

    Spores produced by bacilli and clostridia are surrounded by a multilayered protein shell called the coat. As the armor-like appearance of the coat suggests, this structure, along with others within the spore, confers the remarkable resistance properties that make Bacillus anthracis spores such potent biological weapons. Here, I review recent studies of coat assembly in the model organism Bacillus subtilis, and explore the implications of these findings for coat assembly in B. anthracis and for defense against biological weapons.

  20. Influence of Nano-Al Concentrates on the Corrosion Resistance of Epoxy Coatings

    Institute of Scientific and Technical Information of China (English)

    Yongchun Liang; Fu-Chun Liu; Ming Nie; Shuyan Zhao; Jiedong Lin; En-Hou Han

    2013-01-01

    A two-stage process was used to produce nano-composite epoxy coatings.The first step involved preparing nano-Al concentrates with high concentration and low viscosity,and the second step produced nanocomposite epoxy coatings by mixing the nano-Al concentrates and epoxy resin.Later,the coating was examined with immersion and salt spray tests.The coatings were characterized by electrochemical impedance spectroscopy (EIS),scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS).The results showed that the 5% nano-Al significantly improves the corrosion resistance of the coatings.There are two effects of nano-Al on the coating.Nano-Al is corroded initially to protect the substrate from corrosion,and then the aluminum oxide and aluminum hydroxide were produced after corrosion of nano-Al,which hindered the transmission of corrosion fluid into the coatings.

  1. Photonometers for coating and sputtering machines

    Directory of Open Access Journals (Sweden)

    Václavík J.

    2013-05-01

    Full Text Available The concept of photonometers (alternative name of optical monitor of a vacuum deposition process for coating and sputtering machines is based on photonometers produced by companies like SATIS or HV Dresden. Photometers were developed in the TOPTEC centre and its predecessor VOD (Optical Development Workshop of Institut of Plasma Physics AS CR for more than 10 years. The article describes current status of the technology and ideas which will be incorporated in next development steps. Hardware and software used on coating machines B63D, VNA600 and sputtering machine UPM810 is presented.

  2. Thermal Mechanical Fatigue of Coated Blade Materials

    Science.gov (United States)

    1989-06-01

    Severe Bulk Substrate Damage Following Coating Spallation in PWA 275 Coated PWA 1480 (Quadrilateral Cycle, As = 0.7%, AT = 427-1093-C (800-2000 ’F...90.130 0.329 0.955 0.080 0.765 0.120 View "A" Notes 1. All dimensions in inches Drill and C’sk 2 Holes 180 deg Apart 2. All diameters concentric within...go through an alternating series of first surface oxidation and subsequent spallation . Oxidation was severe enough to produce a substantial loss of

  3. Fluorine Based Superhydrophobic Coatings

    Directory of Open Access Journals (Sweden)

    Jean-Denis Brassard

    2012-05-01

    Full Text Available Superhydrophobic coatings, inspired by nature, are an emerging technology. These water repellent coatings can be used as solutions for corrosion, biofouling and even water and air drag reduction applications. In this work, synthesis of monodispersive silica nanoparticles of ~120 nm diameter has been realized via Stöber process and further functionalized using fluoroalkylsilane (FAS-17 molecules to incorporate the fluorinated groups with the silica nanoparticles in an ethanolic solution. The synthesized fluorinated silica nanoparticles have been spin coated on flat aluminum alloy, silicon and glass substrates. Functionalization of silica nanoparticles with fluorinated groups has been confirmed by Fourier Transform Infrared spectroscopy (FTIR by showing the presence of C-F and Si-O-Si bonds. The water contact angles and surface roughness increase with the number of spin-coated thin films layers. The critical size of ~119 nm renders aluminum surface superhydrophobic with three layers of coating using as-prepared nanoparticle suspended solution. On the other hand, seven layers are required for a 50 vol.% diluted solution to achieve superhydrophobicity. In both the cases, water contact angles were more than 150°, contact angle hysteresis was less than 2° having a critical roughness value of ~0.700 µm. The fluorinated silica nanoparticle coated surfaces are also transparent and can be used as paint additives to obtain transparent coatings.

  4. Phenol-formaldehyde intumescent coating composition and coating prepared therefrom

    Science.gov (United States)

    Salyer, Ival O. (Inventor); Fox, Bernard L. (Inventor)

    1986-01-01

    Intumescent coatings which form a thick, uniform, fine celled, low density foam upon exposure to a high intensity heat flux or flame are disclosed, the invention coatings comprise phenolic resin prepolymer containing a blowing agent and a nucleating agent; in the preferred embodiments the coatings also contains a silicone surfactant, the coatings are useful in thermal and fire protection systems.

  5. Coatings to prevent frost

    DEFF Research Database (Denmark)

    Lusada, Ricardo; Holberg, Stefan; Bennedsen, Jeanette Marianne Dalgaard

    2016-01-01

    The ability of hydrophobic, organic–inorganic hybrid coatings to decelerate frost propagation was investigated. Compared to a bare aluminum surface, the coatings do not significantly reduce the freezing probability of supercooled water drops. On both surfaces, the probability for ice nucleation...... at temperatures just below 0°C, for example at −4°C, is low. Freezing of a single drop on aluminum leads, however, to instant freezing of the complete surface. On hydrophobic coatings, such a freezing drop is isolated; the frozen area grows slowly. At −4°C surface temperature in a +12°C/90% relative humidity...

  6. Determination of parameters for successful spray coating of silicon microneedle arrays.

    Science.gov (United States)

    McGrath, Marie G; Vrdoljak, Anto; O'Mahony, Conor; Oliveira, Jorge C; Moore, Anne C; Crean, Abina M

    2011-08-30

    Coated microneedle patches have demonstrated potential for effective, minimally invasive, drug and vaccine delivery. To facilitate cost-effective, industrial-scale production of coated microneedle patches, a continuous coating method which utilises conventional pharmaceutical processes is an attractive prospect. Here, the potential of spray-coating silicon microneedle patches using a conventional film-coating process was evaluated and the key process parameters which impact on coating coalescence and weight were identified by employing a fractional factorial design to coat flat silicon patches. Processing parameters analysed included concentration of coating material, liquid input rate, duration of spraying, atomisation air pressure, gun-to-surface distance and air cap setting. Two film-coating materials were investigated; hydroxypropylmethylcellulose (HPMC) and carboxymethylcellulose (CMC). HPMC readily formed a film-coat on silicon when suitable spray coating parameter settings were determined. CMC films required the inclusion of a surfactant (1%, w/w Tween 80) to facilitate coalescence of the sprayed droplets on the silicon surface. Spray coating parameters identified by experimental design, successfully coated 280μm silicon microneedle arrays, producing an intact film-coat, which follows the contours of the microneedle array without occlusion of the microneedle shape. This study demonstrates a novel method of coating microneedle arrays with biocompatible polymers using a conventional film-coating process. It is the first study to indicate the thickness and roughness of coatings applied to microneedle arrays. The study also highlights the importance of identifying suitable processing parameters when film coating substrates of micron dimensions. The ability of a fractional factorial design to identify these critical parameters is also demonstrated. The polymer coatings applied in this study can potentially be drug loaded for intradermal drug and vaccine delivery

  7. Polymer coatings as separator layers for microbial fuel cell cathodes

    KAUST Repository

    Watson, Valerie J.

    2011-03-01

    Membrane separators reduce oxygen flux from the cathode into the anolyte in microbial fuel cells (MFCs), but water accumulation and pH gradients between the separator and cathode reduces performance. Air cathodes were spray-coated (water-facing side) with anion exchange, cation exchange, and neutral polymer coatings of different thicknesses to incorporate the separator into the cathode. The anion exchange polymer coating resulted in greater power density (1167 ± 135 mW m-2) than a cation exchange coating (439 ± 2 mW m-2). This power output was similar to that produced by a Nafion-coated cathode (1114 ± 174 mW m-2), and slightly lower than the uncoated cathode (1384 ± 82 mW m-2). Thicker coatings reduced oxygen diffusion into the electrolyte and increased coulombic efficiency (CE = 56-64%) relative to an uncoated cathode (29 ± 8%), but decreased power production (255-574 mW m-2). Electrochemical characterization of the cathodes ex situ to the MFC showed that the cathodes with the lowest charge transfer resistance and the highest oxygen reduction activity produced the most power in MFC tests. The results on hydrophilic cathode separator layers revealed a trade off between power and CE. Cathodes coated with a thin coating of anion exchange polymer show promise for controlling oxygen transfer while minimally affecting power production. © 2010 Elsevier B.V. All rights reserved.

  8. Making silica rock coatings in the lab: synthetic desert varnish

    Science.gov (United States)

    Perry, Randall S.; Kolb, Vera M.; Philip, Ajish I.; Lynne, Bridget Y.; McLoughlin, Nicola; Sephton, Mark; Wacey, David; Green, Owen R.

    2005-09-01

    Desert varnish and silica rock coatings have perplexed investigators since Humboldt and Darwin. They are found in arid regions and deserts on Earth but the mechanism of their formation remains challenging (see Perry et al. this volume). One method of researching this is to investigate natural coatings, but another way is to attempt to produce coatings in vitro. Sugars, amino acids, and silicic acid, as well as other organic and (bio)organic compounds add to the complexity of naturally forming rock coatings. In the lab we reduced the complexity of the natural components and produced hard, silica coatings on basaltic chips obtained from the Mojave Desert. Sodium silicate solution was poured over the rocks and continuously exposed to heat and/or UV light. Upon evaporation the solutions were replenished. Experiments were performed at various pH's. The micro-deposits formed were analyzed using optical, SEM-EDAX, and electron microprobe. The coatings formed are similar in hardness and composition to silica glazes found on basalts in Hawaii as well as natural desert varnish found in US southwest deserts. Thermodynamic mechanisms are presented showing the theoretical mechanisms for overcoming energy barriers that allow amorphous silica to condense into hard coatings. This is the first time synthetic silica glazes that resemble natural coatings in hardness and chemical composition have been successfully reproduced in the laboratory, and helps to support an inorganic mechanism of formation of desert varnish as well as manganese-deficient silica glazes.

  9. Thermal Imaging Processes of Polymer Nanocomposite Coatings

    Science.gov (United States)

    Meth, Jeffrey

    2015-03-01

    Laser induced thermal imaging (LITI) is a process whereby infrared radiation impinging on a coating on a donor film transfers that coating to a receiving film to produce a pattern. This talk describes how LITI patterning can print color filters for liquid crystal displays, and details the physical processes that are responsible for transferring the nanocomposite coating in a coherent manner that does not degrade its optical properties. Unique features of this process involve heating rates of 107 K/s, and cooling rates of 104 K/s, which implies that not all of the relaxation modes of the polymer are accessed during the imaging process. On the microsecond time scale, the polymer flow is forced by devolatilization of solvents, followed by deformation akin to the constrained blister test, and then fracture caused by differential thermal expansion. The unique combination of disparate physical processes demonstrates the gamut of physics that contribute to advanced material processing in an industrial setting.

  10. Hydrodynamically driven colloidal assembly in dip coating.

    Science.gov (United States)

    Colosqui, Carlos E; Morris, Jeffrey F; Stone, Howard A

    2013-05-01

    We study the hydrodynamics of dip coating from a suspension and report a mechanism for colloidal assembly and pattern formation on smooth substrates. Below a critical withdrawal speed where the coating film is thinner than the particle diameter, capillary forces induced by deformation of the free surface prevent the convective transport of single particles through the meniscus beneath the film. Capillary-induced forces are balanced by hydrodynamic drag only after a minimum number of particles assemble within the meniscus. The particle assembly can thus enter the thin film where it moves at nearly the withdrawal speed and rapidly separates from the next assembly. The interplay between hydrodynamic and capillary forces produces periodic and regular structures below a critical ratio Ca(2/3)/sqrt[Bo] particles in suspension. The hydrodynamically driven assembly documented here is consistent with stripe pattern formations observed experimentally in dip coating.

  11. Hard implant coatings with antimicrobial properties.

    Science.gov (United States)

    Moseke, Claus; Gbureck, Uwe; Elter, Patrick; Drechsler, Peter; Zoll, Andreas; Thull, Roger; Ewald, Andrea

    2011-12-01

    Infection of orthopaedic implants often leads to inflammation immediately after surgery and increases patient morbidity due to repetitive operations. Silver ions have been shown to combine good biocompatibility with a low risk of inducing bacterial resistance. In this study a physical vapour deposition system using both arc deposition and magnetron sputtering has been utilized to produce silver ion doped TiN coatings on Ti substrates. This biphasic system combines the advantages of silver induced bactericidity with the good mechanical properties of TiN. Crystallographic analysis by X-ray diffraction showed that silver was deposited as well in its elementary form as it was incorporated into the crystal lattice of TiN, which resulted in increasing hardness of the TiN-coatings. Elution experiments revealed a continuous release of Ag ions in phosphate buffered saline. The coatings showed significant inhibitory effects on the growth of Staphylococcus epidermidis and Staphylococcus aureus and practically no cell-toxicity in cytocompatibility tests.

  12. "m=1" coatings for neutron guides

    DEFF Research Database (Denmark)

    Cooper-Jensen, C.P.; Vorobiev, A.; Klinkby, Esben Bryndt

    2014-01-01

    A substantial part of the price for a neutron guide is the shielding needed because of the gamma ray produced when neutrons are absorbed. This absorption occurs in the coating and the substrate of the neutron guides. Traditional m=1 coatings have been made of Ni and if reflectivity over...... the critical angle of Ni is needed one has used Ni58 or Ni/Ti multilayer coatings. Ni has one of the highest neutron scattering density but it also has a fairly high absorption cross section for cold and thermal neutrons and when a neutron is absorbed it emits a lot of gamma rays, some with energies above 9 Me......V. Materials like diamond and Be have higher neutron scattering density than Ni, have smaller absorption cross section and when a neutron is absorbed they emit much less gamma ray and at lower energies. We present results, both theoretically and experimentally, comparing Ni with Be and preliminary results...

  13. Figure correction of multilayer coated optics

    Science.gov (United States)

    Chapman; Henry N. , Taylor; John S.

    2010-02-16

    A process is provided for producing near-perfect optical surfaces, for EUV and soft-x-ray optics. The method involves polishing or otherwise figuring the multilayer coating that has been deposited on an optical substrate, in order to correct for errors in the figure of the substrate and coating. A method such as ion-beam milling is used to remove material from the multilayer coating by an amount that varies in a specified way across the substrate. The phase of the EUV light that is reflected from the multilayer will be affected by the amount of multilayer material removed, but this effect will be reduced by a factor of 1-n as compared with height variations of the substrate, where n is the average refractive index of the multilayer.

  14. Condensing Heat Exchanger with Hydrophilic Antimicrobial Coating

    Science.gov (United States)

    Thomas, Christopher M. (Inventor); Ma, Yonghui (Inventor)

    2014-01-01

    A multi-layer antimicrobial hydrophilic coating is applied to a substrate of anodized aluminum, although other materials may form the substrate. A silver layer is sputtered onto a thoroughly clean anodized surface of the aluminum to about 400 nm thickness. A layer of crosslinked, silicon-based macromolecular structure about 10 nm thickness overlies the silver layer, and the outermost surface of the layer of crosslinked, silicon-based macromolecular structure is hydroxide terminated to produce a hydrophilic surface with a water drop contact angle of less than 10.degree.. The coated substrate may be one of multiple fins in a condensing heat exchanger for use in the microgravity of space, which has narrow channels defined between angled fins such that the surface tension of condensed water moves water by capillary flow to a central location where it is pumped to storage. The antimicrobial coating prevents obstruction of the capillary passages.

  15. Hybrid calcium phosphate coatings for implants

    Science.gov (United States)

    Malchikhina, Alena I.; Shesterikov, Evgeny V.; Bolbasov, Evgeny N.; Ignatov, Viktor P.; Tverdokhlebov, Sergei I.

    2016-08-01

    Monophasic biomaterials cannot provide all the necessary functions of bones or other calcined tissues. It is necessary to create for cancer patients the multiphase materials with the structure and composition simulating the natural bone. Such materials are classified as hybrid, obtained by a combination of chemically different components. The paper presents the physical, chemical and biological studies of coatings produced by hybrid technologies (HT), which combine primer layer and calcium phosphate (CaP) coating. The first HT type combines the method of vacuum arc titanium primer layer deposition on a stainless steel substrate with the following micro-arc oxidation (MAO) in phosphoric acid solution with addition of calcium compounds to achieve high supersaturated state. MAO CaP coatings feature high porosity (2-8%, pore size 5-7 µm) and surface morphology with the thickness greater than 5 µm. The thickness of Ti primer layer is 5-40 µm. Amorphous MAO CaP coating micro-hardness was measured at maximum normal load Fmax = 300 mN. It was 3.1 ± 0.8 GPa, surface layer elasticity modulus E = 110 ± 20 GPa, roughness Ra = 0.9 ± 0.1 µm, Rz = 7.5 ± 0.2 µm, which is less than the titanium primer layer roughness. Hybrid MAO CaP coating is biocompatible, able to form calcium phosphates from supersaturated body fluid (SBF) solution and also stimulates osteoinduction processes. The second HT type includes the oxide layer formation by thermal oxidation and then CaP target radio frequency magnetron sputtering (RFMS). Oxide-RFMS CaP coating is a thin dense coating with good adhesion to the substrate material, which can be used for metal implants. The RFMS CaP coating has thickness 1.6 ± 0.1 µm and consists of main target elements calcium and phosphorus and Ca/P ratio 2.4. The second HT type can form calcium phosphates from SBF solution. In vivo study shows that hybrid RFMS CaP coating is biocompatible and produces fibrointegration processes.

  16. Advanced thermal barrier coating systems

    Science.gov (United States)

    Dorfman, M. R.; Reardon, J. D.

    1985-01-01

    Current state-of-the-art thermal barrier coating (TBC) systems consist of partially stabilized zirconia coatings plasma sprayed over a MCrAlY bond coat. Although these systems have excellent thermal shock properties, they have shown themselves to be deficient for a number of diesel and aircraft applications. Two ternary ceramic plasma coatings are discussed with respect to their possible use in TBC systems. Zirconia-ceria-yttria (ZCY) coatings were developed with low thermal conductivities, good thermal shock resistance and improved resistance to vanadium containing environments, when compared to the baseline yttria stabilized zirconia (YSZ) coatings. In addition, dense zirconia-titania-yttria (ZTY) coatings were developed with particle erosion resistance exceeding conventional stabilized zirconia coatings. Both coatings were evaluated in conjunction with a NiCr-Al-Co-Y2O3 bond coat. Also, multilayer or hybrid coatings consisting of the bond coat with subsequent coatings of zirconia-ceria-yttria and zirconia-titania-yttria were evaluated. These coatings combine the enhanced performance characteristics of ZCY with the improved erosion resistance of ZTY coatings. Improvement in the erosion resistance of the TBC system should result in a more consistent delta T gradient during service. Economically, this may also translate into increased component life simply because the coating lasts longer.

  17. Polymer coating, germination and vigor of broccoli seeds

    Directory of Open Access Journals (Sweden)

    Almeida Celina de

    2005-01-01

    Full Text Available Brassica oleracea var italica occupies a special place in the internal and external market of vegetables seeds. Vegetables producers demand seeds with high degree of purity, germination and vigor, since seeds' quality is the basis for the success of the production. In this work, broccoli seeds were coated in a spouted bed, by an aqueous suspension of hidroxy-ethyl-cellulose. Effects of the operating variables: spouting air temperature, atomizing air pressure and coating suspension flow rate over the dependent variables: seeds germination, seeds accelerated aging and the speed of seeds germination in soil, were investigated in a factorial scheme trial. The maximum processing time was 120 min. A totally randomized experiment evaluated and compared seeds germination and vigor of the coated and non-coated seeds. There was no identifiable, pronounced difference on germination of coated and non-coated seeds, accelerated aging of seeds, and speed of seeds germination in the soil. Coating with hidroxy-ethyl-cellulose in the spouted bed did not alter broccoli seeds physiologic quality. The surface of coated seeds presented satisfactory distribution and spreading of the polymer film, uniform and individual coating and homogeneous aspect.

  18. Microstructure and properties of sputtered thermal barrier coatings

    Institute of Scientific and Technical Information of China (English)

    Yang Gao; Lun Xie; Feng Pan; Mengcheng Chen

    2004-01-01

    A 3 kW radio frequency (RF) magnetron-sputtering unit was used to produce zirconia ceramic coatings on hollow turbine blades and vanes, which had been deposited a NiCrAlY bond coat layer by cathodic arc deposition. The NiCrAlY coating surface was shot-peened, and the residual stress in the bond coat layer and the effects of heat treatment on the residual stress are presented.After shot peening porosities and microgaps disappear in the NiCrAlY bond coat, the whole depth profile is residual compressive stress. Coarseness tests show that the roughness value (Rz) decreases from 16.4 to 3.3 μm. The microstructure and phase composition of the coatings were investigated using electron probe microanalysis (EPMA) and X-ray diffraction (XRD). The results show that the NiCrAlY bond coat is composed of γ' and Cr phases, and the Al2O3 scales are formed near the interface between the ZrO2 ceramic layer and the NiCrAlY bond coat. No degradation occurred to RF sputtered ceramic coatings after oxidating at 1150℃ for 100 h,heating at 1150℃ for 5 min and then air-cooling for 500 thermal cycles.

  19. Microstructural and Tribological Characterization of Duplex Coatings with Additional Ion Bombardment

    Institute of Scientific and Technical Information of China (English)

    B.(S)kori(c); D.Kaka(s); M.Rakita

    2004-01-01

    A duplex surface treatment involves the sequential application of two surface technologies to produce a surface composition with combined properties. A typical duplex process involves plasma nitriding and the PVD coating treatment of steels. In the paper are presented characteristics of hard coatings, type TiN, produced by classic technology PVD (physical vapour deposition) and IBAD (ion beam assisted deposition). Subsequent ion implantation was provided with N5+ions. The dependence of friction coefficient was investigated by means of tribometer (pin-on-ring). The sliding pair was TiN thin coating on steel pin combined with steel ring without coating. The ring was produced from hardenable steel.

  20. Microstructural and Tribological Characterization of Duplex Coatings with Additional Ion Bombardment

    Institute of Scientific and Technical Information of China (English)

    B.Skorie; D.Kakas; M.akita

    2004-01-01

    A duplex surface treatment involves the sequential application of two surface technologies to produce a surface composition with combined properties. A typical duplex process involves plasma nitriding and the PVD coating treatment of steels. In the paper are presented characteristics of hard coatings, type TiN, produced by classic technology PVD (physical vapour deposition) and IBAD (ion beam assisted deposition). Subsequent ion implantation was provided with N5+ ions. The dependence of friction coefficient was investigated by means of tribometer (pin-on-ring). The sliding pair was TiN thin coating on steel pin combined with steel ring without coating. The ring was produced from hardenable steel.