A novel Hf[sbnd]Si[sbnd]O wire drawing phenomenon after ablation of SiC_nws/HfC[sbnd]SiC coating on C/C composites

A SiC_nws/HfC[sbnd]SiC coating was fabricated by a two-step chemical vapor deposition. After introducing SiC nanowires, the fracture toughness of HfC[sbnd]SiC coating increases by 228%. After ablation under oxyacetylene torch for 60s, a bone-like HfO₂ reticular structure was formed in the central ablation area. Interestingly, a novel Hf[sbnd]Si[sbnd]O wire-drawing phenomenon was happened in the transition area of ablated SiC_nws/HfC[sbnd]SiC coating, providing a new toughness mechanism under ablation environment. Moreover, HfO₂ precipitated from Hf[sbnd]Si[sbnd]O glass wires to generate nanocrystalline grains during ablation, which explains the formation of bone-like HfO₂ reticular structure observed from central ablation area.