Effect of SiCnws@BN core shell upon impact-ablation performance of HfC coating on C/C composites

To improve the thermal protection performance of HfC coating subject to impact, SiCnws@BN core-shell nano -wire reinforced HfC coating was fabricated by chemical vapor deposition and compared to the SiCnws@PyC/HfC coating. The experiments showed that the ablation resistance of SiCnws@PyC/HfC coating decreased signifi-cantly. In comparison, the ablation resistance of SiCnws@BN/HfC coating was barely affected by impact. A dense oxide layer was formed on the surface of SiCnws@BN/HfC coating after impact and ablation. The shrinking and self-healing effect of SiCnws@BN during oxidation process was investigated, which explained the formation process of dense oxide layer.