Mechanical properties and microstructures of 2D Cf/ZrC–SiC composites using ZrC precursor and polycarbosilane

Two-dimensional Cf/ZrC–SiC composites were fabricated through mold-pressing and polymer infiltration and pyrolysis (PIP) using T700SC plain weave fiber fabrics as reinforcements with ZrC precursor and polycarbosilane. The mechanical properties and microstructures of the composites with 34, 45, and 56% fiber fraction were investigated. All composites showed a typical non-brittle fracture behavior and a large amount of pulled-out fibers were observed on the fracture surface. The bending strength and elastic modulus of the composite with 56 vol% fiber fraction increased up to 582 ± 80 MPa and 167 ± 25 GPa, with increasing fiber fraction. The mass loss and linear recession rate of the composites during the oxy-propane torch test were 0.008 g/s and −0.003 mm/s, respectively. The formation of a ZrSiO4 melt on the surface of the composite significantly contributed to the excellent ablative property of the 2D Cf/ZrC–SiC composites.