Ablation resistant C/C-HfC-ZrC-TaC-SiC composites prepared by reactive melt infiltration

Ultra-high temperature ceramics (UHTCs) modified C/C composites for extreme high-temperature environments are fascinating, the rapid introduction of UHTCs and structural temperature resistance are essential for the long-term service. Herein, C/C-HfC-ZrC-TaC-SiC composites with continuous ceramic-rich layers were designed and prepared to improve the ablation resistance. HZT441 (HfC:ZrC:TaC = 4:4:1) sample exhibited pseudo-plastic fracture with a flexural strength of 195.27 +/- 11.11 MPa. After 80 s of oxyacetylene ablation (4.2 MW/m(2)), the mass and linear growth rates were 0.10 mg/s and 1.02 mu m/s. This is attributed to the dense oxide layer, including (Hf,Zr)(6)Ta2O17, (Hf,Zr)O-2 and SiO2, which effectively inhibits oxygen intrusion and carbon fiber damage. In addition, the thermal response behavior and stress distribution of ceramic-rich layers to C/C composites were investigated, which is contributed to provide a theoretical basis for the material design of thermal protection systems in extreme high-temperature environments.