A novel Cr-doped Al2O3-SiC-ZrC composite coating for ablative protection of C/C-ZrC-SiC composites

A novel Cr-doped Al2O3-SiC-ZrC coating systemis proposed to further improve the ablation resistance of C/CZrC-SiC composites. Our approach combines low pressure plasma spray method with slurry impregnation of ZrCr-Si-C to achieve a specially tailored oxide-carbide structure. Results show that the as-prepared coating was dense and crack-free, which effectively promoted the ablation resistance of C/C-ZrC-SiC with the mass and linear ablation rates decreased by 66% and 76% respectively, involving a highly dense protective structure of AlxCr2-xO3-SiO2-ZrO2 formed during ablation. The compact and continuous multi-oxide scale with ZrO2-rosette skeleton intricated with A1(1.96)Cr(0.04)O(3) was evidenced in the ablation center.