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A combinatorial process has been developed for the high throughput production and evaluation of surface coatings. The workflow designed for the production of arrays of liquid coatings involves the robotic transfer of aliquots of solutions of raw materials to an array of glass vials and mixing of the coatings using an unconventional magnetic stirring process. An investigation of the capability of the workflow to accurately and repeatedly prepare coating arrays was conducted as a function of solution viscosity and aliquot size. In addition, mixing capability was evaluated as a function of solution viscosity, total solution volume, and mechanism of stirring. Overall, the results of the study indicated that adequate accuracy and repeatability of the coating preparation process can be achieved as long as raw material solutions are designed such that viscosity is below about 250 cP and aliquot sizes are above about 75 μl. With regard to mixing capability, total solution volume was found to have a profound affect as did the stirring mechanism. 相似文献
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Study on corrosion resistance and roughness of micro-plasma oxidation ceramic coatings on Ti alloy by EIS technique 总被引:2,自引:0,他引:2
Micro-plasma oxidation (MPO) technique has been developed quickly in recent years. The produced ceramic coatings are reported to possess fine properties and promising application prospects in many fields. The aim of this work is to study the corrosion resistance and the roughness of the micro-plasma oxidation ceramic coatings on Ti alloy by electrochemical impedance spectroscopy (EIS) technique. Compound ceramic coatings were prepared on Ti-6Al-4V alloy by pulsed bi-polar micro-plasma oxidation in NaAlO2 solution. The phase composition and element distribution in the coating were investigated by X-ray diffractometry and electron probe micro-analyzer. EIS of the coatings was measured through CHI604 electrochemical analyzer in 3.5% NaCl solution. The ceramic coating is composed of a large amount of Al2TiO5 and a little α-Al2O3 and rutile TiO2. The coating is of double-layer structure with the loose outer layer and the dense inner layer. The thickness of the coatings is reduced when the working frequency or the cathode pulse current density is increased, while the thickness is increased when the frequency or the anode current density is increased. The established “equivalent circuit” of the coatings is consistent with the double-layer structure. The electric charge transfer resistance (Rt) in the equivalent circuit can be used to assess the corrosion resistance of the coatings, which is consistent with the result of the polarizing curves test. And the empirical exponent (n1) of the constant phase element (Q1) in the equivalent circuit can be used to assess the surface roughness of the coatings, which is consistent with the surface SEM analysis of the coatings. 相似文献
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Ambient‐cured polyesteramide (APEA) coating resin synthesized from dihydroxy fatty amide obtained from linseed oil, a sustainable resource, and poly(styrene‐co‐maleic anhydride), a bifunctional acid component, was found to exhibit improved physicomechanical and anticorrosive properties. The structural elucidation of APEA resin has been carried out by FTIR, 1H‐NMR, and 13C‐NMR spectroscopies. The physicomechanical and chemical resistance properties were investigated by standard methods. The corrosion resistance performance was evaluated in acid, alkali, and organic solvent. The thermal behavior was studied by TGA technique. A comparative study of these properties of APEA with reported baked polyesteramide (PEA) coatings was carried out. A remarkable improvement in the drying property of APEA was observed. The APEA coatings also showed improved physicomechanical and anticorrosive properties as compared to the baked PEA coatings. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1818–1824, 2005 相似文献
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In this paper we describe an apparatus for reproducibly measuring thermal shock resistance of thick polymer layers bonded to metals. The thermal shock behavior is discussed in terms of epoxy samples bonded to an aluminum substrate. It was found that both high resin toughness and low resin thermal expansion coefficient improved thermal shock resistance of thick coatings, but only a sample containing 60wt. % glass beads did not develop a failure crack. Effects of sample thickness, temperature gradient, and resin composition on thermal shock behavior are discussed. 相似文献
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Michael Kmetz Steven L. Suib Francis S. Galasso 《Journal of the American Ceramic Society》1989,72(8):1523-1524
The strength and toughness of fibrous composites depend on the interface properties which control the bonding between the fibers and matrices. One method of controlling the interface involves coating the fiber with an appropriate material. In a previous study, it was found that there is a definite advantage in using low coating temperatures to prevent fibers from degrading. We therefore were interested in a report that Mo2 C could be deposited from Mo(CO)6 at temperatures as low as 300° to 475°C. Our studies indicated that the material was not Mo2 C, but an oxycarbide, which, with an analogous tungsten oxycarbide coating, was applied to SiC yarns. Both oxycarbides could be converted to the metals by heat-treating in N2 . 相似文献