Water and oxygen corrosion resistance of SiC_f/SiC–SiYBC composites prepared by reactive melt infiltration at 1300°C –1500°C

In this work, the static water and oxygen corrosion behavior of SiC_f/SiC–SiYBC composites was systematically studied at 1 300°C to 1 500°C. With the increase in corrosion temperature from 1 300°C to 1 500°C, both the residual strength and strength retention rate of SiC_f/SiC–SiYBC composites initially increased and then decreased. The highest strength retention rate achieved was 132%, which was 35% higher than that of SiC_f/SiC composites. During water and oxygen corrosion of composites, self-healing boron silicate glass and the Y₂Si₂O₇ phase with excellent resistance to water and oxygen were generated in situ. The oxidation products are fluid at high temperatures and can fill internal pores and microcracks, thus improving the residual strength of the SiC_f/SiC–SiYBC composite. The water corrosion resistance of SiC_f/SiC–SiYBC materials has been confirmed to be superior to that of SiC_f/SiC composites.