Microstructures and mechanical properties of a low-cost three-dimensional needled carbon/silicon carbide composite

Unidirectional air-pressure impregnation combined with hot-pressing curing is a low-cost and short-time fabrication of a three-dimensional needled carbon/carbon (C/C) composite. Its density of 1.26 g/cm³ was achieved via one phenolic resin impregnation-pyrolysis cycle. The increase in volume content of carbon fibers by 67% was achieved. The C/C composite was transformed into a carbon/silicon carbide (C/SiC) composite with a density of 2.00 g/cm³ by liquid silicon infiltration. The microstructures at every stage of preparation process and the mechanical properties of the final C/SiC composite were investigated. The results indicated that the C/SiC composite which contained dense C/C substructures was composed of 53 wt% C, 44 wt% SiC and 3 wt% Si. The C/SiC composite showed a flexural strength of 82 MPa and non-brittle fracture behavior.