Abstract：SiCf/SiC composites combustor liner which consists of inner liner, outer liner, left and right plate prepared by chemical vapour infiltration process (CVI), was exposed to simulated aero-engine service environment by sector combustor rig. A three-layer BSAS/Mullite/Si environmental barrier coating (EBC) was deposited on the flow surface of the combustor liner by atmospheric plasma spraying. The evolution of the defect, mechanical property, microstructure and surface phase composition of the composite liner subjected to combustion environment were evaluated by mechanical test, scanning electron microscope and X-ray diffraction, respectively. The results indicate that the as-sprayed coating is mainly composed of monoclinic celsian BSAS phase and BaAl2O4 phase; After the sector combustor test, the core ablation area is mainly composed of orthorhombic mullite phase Al2（Al2.8Si1.2）O9.6 , cubic Si, and BaAl2O4 phases. Meanwhile, silicon droplets and holes can also be observed on the surface. In addition, the results of mechanical properties after the burner rig test show that the tensile strength of SiCf/SiC composites in the coating integrity area is not affected, while that of the core ablation area decreased significantly. The high-temperature ablation mechanism of the coating was discussed at final.
2022, 
