| With the development of modern science and technology, high performance materials are called for by industry. For the increasing harsh working conditions, materials used are needed to have good properties, such as corrosion-resistance that the pure metallic materials can not satisfy the requirements. Ceramic materials have good corrosion-resistance and wear-resistance, therefore, Metal matrix ceramic coatings (MMCs) obtained by coating the ceramic evenly on the surface of metal through certain technologies has both metal's good physical mechanical property and ceramic's advantages. As a result, the research of MMCs gets many scientists' attention and becomes a new hot spot.The preparation methods of MMCs and its wear-resistance,corrosion-resistance were investigated. The electrophoretic deposition and the enamel technology were used, the parameters of the preparation were analyzed and the optimal conditions were summarized. The primary works of this paper are summarized as follows:1. The Al2O3 sol was prepared by hydrolyzation using the inorganic salt water solution as the raw materials. Electrophoretic deposition was used to deposit Al2O3 colloid particles which has electrophoresis characteristic on the stainless steel, Al2O3 ceramic coating was obtained after the low temperature sintering. Results indicated that the dispersant and the density of the sol, the electrophoretic deposition time and the sintering schedule would affect the corrosion-resistance performance of the samples. The appropriate preparation condition is that the stainless steel was put into Al2O3 sol in which ethanol was used as the dispersant and deposited for 180s under 60V electric potential, then sintered in the muffle furnace at 800℃for 5min. The Al2O3 ceramic coating as-obtained has good corrosion-resistance performance which the corrosion rate of the sample in 2mol/L hydrochloric acid is 0.27g/(cm2·h). But, due to the different thermal-expansion coefficient between the Al2O3 coating and the stainless steel, the sample was easy to crack during calcination.2. The enamel technology was a good method to prepare the ideal ceramic coating. The composition of bottom-glaze and surface-glaze were studied. The bottom-glaze can combine with the stainless steel effectively and alleviate the thermal-expansion coefficient differences between them, while the surface-glaze can achieve the requirement of wear-resistance and corrosion-resistance. The composition and sintering schedule of the crystallite surface-glaze (the MgO-Al2O3-SiO2 system) were studied in detail. Results showed that, B2O3 in the composition can be both the network organizator and strong flux which may reduce the firing temperature of the surface-glaze.3. The samples as-prepared has good corrosion-resistance which the corrosion rate in 2mol/L hydrochloric acid was only 0.15g/(cm2·h) and the surface would emerge scratches as long as the load reached 360g. These properties of the samples as-prepared have great enhancement than both the stainless steel and the samples prepared before. At the same time, results showed that the sintering schedule has great influence on the crystallization performance of the surface-glaze. The optimal sintering schedule of the surface-glaze is that: sintering temperature is 800℃, sintering time is 5minutes and then cooling down immediately in air atmosphere.
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