Microstructure and Mechanical Properties of SiC and Carbon Hybrid Fiber Reinforced SiC Matrix Composite

Silicon carbide (SiC) matrix composite reinforced by both SiC and carbon fibers ([SiC–C]/pyrolytic carbon [PyC]/SiC) was fabricated by chemical vapor infiltration for reducing matrix microcracks. Microstructure, mechanical properties, and oxidation resistance of the composite were compared with those of C/PyC/SiC and C/PyC HT /SiC composites in which PyC interphase was untreated and heat‐treated at 1800°C in argon, respectively. Compared with the C/PyC/SiC composite, (SiC–C)/PyC/SiC composite shows considerable improvements in flexural strength, fracture toughness, and oxidation resistance. The different mechanical behaviors of the three composites were analyzed based on the He and Hutchinson's model.