Enhanced thermal shock resistance of SiCf/SiC composites with Y-Al-Si-O glass ceramic environmental barrier coatings in water-oxygen conditions at 1350 °C

In this study, Y-Al-Si-O(YAS) glass-ceramic environmental barrier coatings were prepared after modifying CVISiCf/SiC composites with microcrystalline glass. The resistance of both SiCf/SiC and SiCf/SiC with YAS-EBC to thermal shock was systematically examined using a water quenching method. The findings demonstrate that the SiCf/SiC composites with YAS-EBC exhibits outstanding thermal shock resistance. The coefficient of thermal expansion (CTE) of the YAS coating exhibits minimal deviation from that of SiCf/SiC and possesses a low modulus of elasticity. Upon experiencing thermal shock, the YAS coating is subjected to tensile stress, with an average thermal stress of merely similar to 4.4 MPa. After undergoing 100 cycles, there was no evidence of debonding between the coating and the substrate, nor was a thermally grown oxide (TGO) layer observed at the interface. This research provides a credible method and theoretical foundation for enhancing the thermal shock resistance behavior of CVI-SiCf/SiC composites.