A novel approach for preparing a SiC coating on a C/C-SiC composite by slurry painting and chemical vapor reaction

In order to improve the oxidation resistance of C/C-SiC composites, a SiC coating was prepared on a C/C-SiC composite by slurry painting combined with a chemical vapor reaction process. The oxidation resistance and microstructural evolution of the coated samples were investigated. The results show that the as-prepared SiC coating contained a large amount of residual silicon, and the presence of these Si promoted the formation of a complete SiO2 glass layer in the initial stage of oxidation. However, the evaporation of the residual Si also accelerated the failure of the SiC coating, which caused the weight loss of the sample to be about 2.2% after oxidation in static air at 1500 degrees C for 300 h. Attributed to a large number of SiC ceramics in the C/C-SiC composite, the oxidation weight loss rate of the coating sample after coating failure was reduced.

Automated summary

In this study, a SiC coating was successfully prepared on a C/C-SiC composite using slurry painting combined with a chemical vapor reaction process to enhance its oxidation resistance. The presence of residual silicon in the coating promoted the formation of a complete SiO2 glass layer in the initial oxidation stage, but also accelerated the failure of the coating. However, due to the presence of a large number of SiC ceramics in the composite, the oxidation weight loss rate of the coating sample after coating failure was reduced.