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 B₂O₃ 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.

ZrSiO₄ bulk was prepared by pressureless sintering process and ZrSiO₄ coating was deposited on the SiC_f/SiC substrate using air plasma method. The microstructures of ZrSiO₄ bulk and ZrSiO₄ coating are both dense. A preliminary study of a water vapor corrosion test for ZrSiO₄ bulk and ZrSiO₄ coating was performed under the conditions of 1.013×10⁵ Pa, 90%H₂O/10%O₂, 1300°C, and low gas velocity. Results show that some pores appear on the surface of the ZrSiO₄ bulk. The main crystal phase is ZrO₂ and the weight loss of ZrSiO₄ bulk is only 0.236 mg/cm² after corrosion. The ZrSiO₄ coating peels off from the substrate after 10₉ h. The number and intensity of diffraction peaks of ZrO₂ in the coating increase, and the major crystal phase of the coating is still ZrSiO₄. A porous microstructure accompanied with cracks is observed on the surface of ZrSiO₄ coating after corrosion.