High Temperature, Corrosion-resistant, Antioxidant And Anti-erosion, High Temperature Inorganic Coatings

The component optimization, stable dispersion of CMX98-1 nanocoating as well as the oxide behave of coating/matrix (alloy) system and the optimization of flow coating technics at the sect of elevated-temperature turbine pump wall were investigated. From above mentioned experiment, it can be concluded that:1. Addition of sodium citrate and sodium carboxymethyl cellulose to CMX98-1 nanocoating can effective increase the stability and dispersion of super-micrometer in the coating. Whilst addition of 0.1% sodium citrate at PH=7~8 can obtain ideal stability and dispersion for the CMX98-1 nanocoating.2. CMX98-1 coating material showed good resistance to thermal shock and heat oxide at high temperature. From the comparison of the elevated-temperature oxide behave of alloy surface between the GH202 alloy with coating and none-coat alloy, it shows that CMX98-1 coating with nanometer ceramics can effective inhibit oxygen to diffuse to matrix which resulted in the improved inoxidizability.But the oxygen also can diffuse to matrix through coating or metal surface whether it has coating or not. The difference between them lies in the magnitude of diffusion rate and diffusion flux.3. The element Chromium and Aluminium of the matrix diffused to surface of coating/matrix by upgrade diffusion whilst the oxygen atom in the surroundings diffused to matrix through coating. A layer of C^Oa anear coating and intercrystal oxide anear matrix were formed during annealing at 1000"C. Those kinds of oxide layers become thicker and thicker with the increase of annealing time.4. The viscosity, dope and flow coating process were optimized by means of theoretical analysis on flow coating technics at the sect of elevated-temperature of the turbine pump wall and a flow coating technics satisfied to quality requirements were obtained.