| In order to improve wear and corrosion resistance of Q235 steel, preparation of ceramic coating on the surface of Q235 steel by solid-state reaction method. With SiO2 and Al2O3 as the aggregate, MgO as the curing agent, Na2O as the flux, aluminum phosphate as adhesive, obtained SiO2-Al2O3 ceramic coating (micron ceramic coating and nanometer ceramic coating), their wear and corrosion resistance improve small than the matrix, nanometer coating performance better than the micron coating slightly. Analysis of solid-state reaction mechanism of SiO2 and Al, from 298K to 2000K,ΔGTθis larger negative, show that SiO2-Al reaction is spontaneous,ΔHTθis also larger negative, show that the reaction emit a lot of heat, SiO2 and Al composite powder treatmented by the mechanical alloying, can reduction the temperature of solid-state reaction significantly, by calculating the activation energy, show that the SiO2-Al reaction kinetics mechanisms are reaction-diffusion model. Introduction the SiO2-Al and its mechanical alloying technology into preparation ceramic coating by solid-state reaction, in order to strengthen the solid-state reaction of ceramic coating, get excellent performance of ceramic coating. The results show that, with SiO2 and Al as the aggregate, MgO as the curing agent, CrO3 as a defoamer, aluminum phosphate as adhesive, obtained aluminum phosphate SiO2-Al system ceramic coating, their wear and corrosion resistance have been improved greatly than the matrix, and the performance of coating curing at 800℃is superior to curing at 400℃. With SiO2 and Al as the aggregate, MgO as the curing agent, water glass as the adhesive, obtained water glass SiO2-Al system ceramic coating, compared with the aluminum phosphate SiO2-Al system ceramic coating, analysis of the impact of two kinds of adhesive on the properties of ceramic coating, the results showed that, in the environment with corrosive medium or rapid change temperature, use the aluminum phosphate ceramic coatings is better, in the wear occasions should choose to water glass ceramic coating.
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