Preparation of carbon fiber-reinforced SiC ceramics by stereolithography and secondary silicon infiltration

Stereolithography is an extremely effective three-dimensional (3D) printing technology for the rapid fabrication of high-precision, complex-shaped, and large-scale SiC-based ceramic composites. The combination of photopolymerization-based additive manufacturing and liquid silicon infiltration (LSI) process has been widely used for fabricating lightweight and high-strength carbon fiber-reinforced SiC (C-f/SiC) ceramic matrix composites. However, the fracture toughness of C-f/SiC ceramics prepared by LSI is generally low due to the erosion of carbon fibers by liquid silicon. In this study, we propose a novel fabrication route for C-f/SiC composites by introducing SiC-protected carbon fibers in the photosensitive SiC slurry to prevent the erosion of carbon fibers during the LSI. The fracture toughness of the composites is significantly improved due to the addition of carbon fibers, and it is also much better than the previously reported value for C-f/SiC ceramics. Overall, this study provides an effective strategy for the refined and mass production of ceramic matrix composites.