Microstructures and mechanical properties of 3D 4-directional, Cf/ZrC–SiC composites using ZrC precursor and polycarbosilane

•Three-dimensional 4-directional Cf/ZrC–SiC composites fabricated by polymer infiltration and pyrolysis.•The microstructure and mechanical properties of the composites were studied.•High-temperature oxidation resistance and anti-ablation properties were evaluated.•Results show the composites have good mechanical and excellent ablative properties.

Three-dimensional 4-directional Cf/ZrC–SiC composites were successfully fabricated by polymer infiltration and pyrolysis combined with ZrC precursor impregnation. The microstructure and mechanical properties of the composites were studied. The composite with PyC/SiC interphase had a bulk density of 2.14 g/cm3, an open porosity of 10%, and a bending stress of 474 MPa, and exhibited a non-brittle failure behavior due to propagation and deflection of cracks, and fracture and pullout of fibers. Their high-temperature oxidation resistance and anti-ablation properties were evaluated using a muffle furnace and plasma wind tunnel test. Results show that the composites have good mechanical and excellent ablative properties.