Ablation behavior of a carbon fabric reinforced phenolic composite modified by surface-decorated ZrB₂/SiC

Carbon fabric reinforced phenolic composites were widely used as TPSs (thermal protection system) material in the aerospace industry. However, their limited oxidative ablation resistance restricted their further utility in more serious service conditions. In this study, the surface-decorated ZrB₂/SiC and its modified carbon fabric reinforced phenolic composites have been successfully prepared. The self-modification mechanism of the surface-decorated ZrB₂/SiC particles were characterized. The mechanical performance and ablation behavior of the composites were investigated. Results showed that the ZrB₂/SiC particles possessed a good surface-decorated effect, which achieved good compatibility with the phenolic resin. The mechanical performance of the modified phenolic composite was effectively improved. The anti-oxidative ablation performance of the composite was improved. The mass ablation rate of the surface-decorated ZrB₂-SiC-modified carbon fabric reinforced phenolic composites was 25% lower than that of the unmodified composites. The formed ZrO₂ ceramic layer attached to the surface of the residual chars prevented the heat energy and oxygen from the inner material. Meanwhile, the volatilization of SiO₂ and B₂O₂ effectively increased the heat dissipation. All these results confirmed that the ZrB₂-SiC particles can effectively improve the ablation resistance of the composite, which provided a basis for the application of the composites to more serious service environments.