Preparation of SiC coated graphite composite powders by nitriding combustion synthesis

Ceramics-coated graphite powders are considered an effective raw material to fabricate the three-dimensional continuous ceramics skeleton reinforced matrix composites which can overcome their inherent poor densification, mechanical and antioxidation properties. However, morphology thickness regulation of ceramic coatings on particles still a great challenge. Herein, SiC-coated (graphite@SiC) were prepared by nitriding combustion synthesis using Si graphited mesocarbon microbead (MCMB) as with polytetrafluoroethylene (PTFE) promoter. The effects PTFE content Si/MCMB molar ratio phase composition coating investigated. transition microstructure evolution CS process revealed gas-released quenching experiment. When was 1:3 10 wt.%, SiC synthesized under 2 MPa N2 reached 1.14 μm. corresponding sintered graphite@SiC composite had relative density 99.2% flexural strength 231 MPa, accompanied significant improvement in high temperature as-synthesized good sinterability properties show promise for application nuclear industry other extreme fields.