Ultra-high temperature ceramic coating for carbon/carbon composites against ablation above 2000 K

Abstract

To improve the ablation resistance of carbon/carbon composites at the temperature above 2000K, a ZrB2-SiC-ZrC ultra-high temperature ceramic coating was prepared by combination of supersonic atmosphere plasma spray (SAPS) and reaction melt infiltration. The micro-holes in ZrB2-Si-ZrC coating prepared by SAPS were effectively filled and the compactness and interface compatibility between the coating and C/C composites was improved through the reaction melt infiltration process. The ultra-high temperature ceramic coating exhibited good ablation resistance under oxyacetylene torch ablation above 2000K. After ablation for 120s, the mass and linear ablation rates of the ZrB2-SiC-ZrC coated C/C samples were only −0.016 × 10−3g/s and 1.30µm/s, respectively. Good ablation resistance of the ultra-high temperature ceramic coating is mainly attributed to the dense coating structure and the improvement of interface compatibility between the coating and C/C composites.