Csf/SiBCN–ZrB2 composites prepared by in-situ reaction: Plasma ablation behavior at different durations

Short-cut carbon fiber reinforced SiBCN ceramic matrix composites were prepared using in-situ carbothermal reduction and reactive hot-press sintering, and their properties were investigated. The addition of silica fume modified the matrix phase ratio, promoting densification and increasing the composite density from 2.43 to 2.67 g/cm 3 . The mechanical properties of the composites were significantly improved with the addition of silica; flexural strength and fracture toughness increased by 54.3 and 39.4 %, respectively. Pronounced crack deflection was observed during fracture. The ablation performance of the composites was evaluated using plasma flame ablation at different durations. The addition of silica fume significantly reduced ablation loss across all the tested durations, with the linear ablation rate decreasing by 34.7 % after 300 s of ablation. This work provides a promising fabrication route for the synthesis of SiBCN composites.