Self-densification behavior, interfacial bonding and cyclic ablation resistance of HfSi2-ZrSi2 modified SiC/ZrB2-SiC/SiC coating for Cf/SiC composite

A slurry method has good prospects in preparing coatings, yet great challenge to apply dense coatings due to the volatilization of slurry and the inert and pressureless sintering. Here we develop aHfSi(2)-ZrSi2 modified SiC/ZrB2-SiC/SiC triple-layer coating by an improved slurry method combined with CVD on C-f/SiC composites. The ZrSi2 and HfSi2 are preferentially oxidized in a novel oxygen-containing sintering process so that their generated SiO2 glass can heal defects to achieve self-densification of the coating. Resultantly, the coating presents outstanding interfacial bonding strength of 14.7 MPa and excellent cyclic ablation resistance at 1800 ? for 600 s

Automated summary

We have developed a aHfSi(2)-ZrSi2 modified SiC/ZrB2-SiC/SiC triple-layer coating with excellent interfacial bonding strength and cyclic ablation resistance. This is achieved through an improved slurry method and chemical vapor deposition on C-f/SiC composites.