High temperature corrosion of (Er_(0.25)Tm_(0.25)Yb_(0.25)Lu_(0.25))_2Si_2O_7 environmental barrier coating material subjected to water vapor and molten calcium-magnesium-aluminosilicate (CMAS)

摘要

Environmental barrier coatings (EBCs) are being developed to improve the durability of SiCf/SiC CMC components against harsh combustion environment. Among the most promising EBC candidates, rare-earth (RE) disilicates attract attentions for the good thermal and chemical compatibility with SiC CMCs. We herein investigate the high temperature corrosion resistances of a new multicomponent beta-(Er0.25Tm0.25Yb0.25Lu0.25)(2)Si2O7 disilicate subjected to hot water vapor and molten CMAS. Multicomponent (Er0.25Tm0.25Yb0.25Lu0.25)(2)Si2O7 shows superior water vapor corrosion resistance at 1400 degrees C and significantly enhanced CMAS resistance at 1500 degrees C compared with single principal RE disilicates. The present results highlight the merit of multiple RE engineering in advanced EBCs for the improvement of crucial high temperature corrosion resistances in engine applications.