Preparation and property of C_f/HfC composites by liquid impregnation combined reactive melt infiltration

The C_f/HfC composite was prepared by liquid impregnation combined reactive melt infiltration technique. The impregnation efficiency, anti-oxidant and anti-ablation particles distribution morphology, infiltration efficiency and infiltration organization were studied, the antioxidant ablation property and mechanical properties of C_f/HfC composites were also assessed. Results show that the modified C/C preform which contains 13wt% ZrB₂+HfO₂+TaSi₂ particles was obtained after five cycles of impregnation-carbonization and one high-temperature treatment process, the density and open porosity of which are 1.41 g/cm³ and 24.84%, respectively. Particles are mainly distributed in matrix carbon between fiber bundles, and the distribution is uniform. The C_f/HfC composites whose density and open porosity are 2.98 g/cm³ and 12.95%, was prepared after Hf35Zr10Si5Ta alloy reactively melt infiltrated modified C/C perform. The linear ablation rate is 0.017 1 mm/s, the flexural strength is 173.76 MPa, and the fracture mechanism is pseudo-ductile fracture.