Optimizing PyC matrix interface to improve mechanical properties of carbon/carbon composites by rod-like SiOC ceramic

Rod-like SiOC ceramic in-situ reinforced carbon/carbon (C/C) composites have been synthesized in this work. The rod-like SiOC ceramic growth mechanism was investigated. By optimizing the interfaces, simultaneously, mechanical strength of C/Cs could be improved. Firstly, in order to protect and strengthen carbon fibers (CFs), about 200 nm carbon layer was deposited on the surface of CFs. Then SiOC ceramic were in-situ grown in the C/Cs preform. After the densification through TGCVI, the bending and ILSS test revealed that these optimal designs including the carbon buffer layer and SiOC reinforcements between the fiber/matrix (F/M) and matrix/matrix (M/M) interfaces endowed C/Cs with improved bending strength by 118.85% and ILSS by 92.2%, respectively. Raman results also demonstrated that the defects in C/C composites could be significantly reduced by introducing SiOC ceramic and optimizing carbon layer.