Ablation behaviour and mechanical performance of ZrB2-ZrC-SiC modified carbon/carbon composites prepared by vacuum infiltration combined with reactive melt infiltration

• A novel vacuum infiltration combined with reactive melt infiltration (RMI) method successfully produced C/C-ZrB2-ZrC-SiC composites with higher ceramic content and more uniform distribution compared to traditional RMI. • The C/C-ZrB2-ZrC-SiC composites exhibited significantly improved ablation resistance, with mass and linear ablation rates reduced by 68.9% and 29.7%, respectively, relative to C/C-ZrC-SiC composites. • The enhanced ablation performance is attributed to the volatilization of B2O3 (heat dissipation) and the formation of a continuous ZrO2-SiO2 protective layer that hinders oxygen infiltration. • This work provides a promising, efficient route for fabricating high-performance thermal-structural materials for advanced aerospace applications.