Properties and microstructure of Cf/HfC‐SiC composite prepared by combined process

Abstract The C f /HfC‐SiC composite was produced by precursor infiltration and pyrolysis combined with gaseous silicon infiltration and an open porosity as low as 5.4% was achieved. C f /HfC‐SiC composite has a thermal conductivity of 21.4 W·m −1 ·K −1 , in addition, its flexural strength, elastic modulus, and fracture toughness are 328.9 ± 58.4 MPa, 48.9 ± 2.8 GPa, and 10.2 ± 1.2 MPa·m 1/2 , respectively. The compact matrix and the toughing mechanism by fibers account for the good mechanical properties. The C f /HfC‐SiC composite survives the oxyacetylene torch test and the formation of a protective oxide scale by joint action of SiO 2 and HfO 2 contributes to good ablation performance of the composite.