Analysis and testing of C/C-SiC composites prepared by CVI+PIP process

This paper uses the CVI + PIP process to prepare C/C-SiC composites and thoroughly investigated the effects of the combined process on the microstructure and mechanical properties of ceramic matrix composites, and conducted structural observation and ablation characteristics tests on the prepared specimens. The structural observation results indicated that the combined processing, through densification and co-deposition, significantly improved the density and uniformity of composite. Ablation characteristics tests showed that the oxidation of SiC formed a SiO₂ protective layer, greatly enhancing the composite’s oxidation resistance. Based on the observation results, a microstructural model encompassing fibers, interphase (including zero-thickness interfaces), cross-link bonds, and pores was constructed and analyzed using finite element methods. The analysis results demonstrated that moderate cross-link and bonding between fibers, optimized crack propagation and deflection between the matrix and interface, enhancing the strength and toughness of C/C-SiC composites, and had a positive effect on improving their mechanical properties.