环境障涂层的发展瓶颈及应对措施

Silicon-based ceramic has broad application prospect as high temperature structure materials in aero engines due to low density and excellent mechanical properties. In high-temperature steam environment, silicon-based ceramic will react with high temperature steam to form volatile Si(OH)₄. Si(OH)₄ can be brushed away by high velocity steam, leading inner silicon-based ceramic exposing in high temperature steam environment. So we need to prepare environmental barrier coating (EBC) on the surface of silicon based ceramic to protect it from high temperature steam. The limiting factors of the development of first and second generations EBC are clearly pointed out in this review. We highlight the problems the third generation EBC facing from the perspectives of rare earth silicate top layer and silicon bonding layer. The corresponding solutions of the problems the third generation EBC facing are also elaborated. This review is of great significance in the selection of materials of up-to-date EBC.