LAUSR

Abstract Micro-diamond modified C/C composites (C/C-D composites) were fabricated using pressureless infiltration (PI) and chemical vapor infiltration (CVI) methods. And the influence of diamond graphitization on the microstructure and performance of C/C-D composites were investigated. During further graphitization process of diamond particles (1600 °C), thicker graphite layer formed on diamond surface accompanied by volume expansion, which induced stress graphitization to surrounding PyC. Meanwhile, the graphite/PyC interface bonding strength improved significantly after diamond graphitization. Compared with the low strength retention rate of C/C composites (46.8%) after heat treated at 1600 °C, a high strength retention rate was achieved for C/C-D composites (87.1%) benefiting from the enhanced graphite/PyC interface bonding strength after diamond graphitization. And the thermal conductivity of the as-prepared C/C-D composites increased by 32.5% with the addition of diamond particles (9.97 wt%). It could be expected that C/C composites with optimal microstructure and excellent performances can be obtained by adjusting the content and graphitization degree of diamond particles in future work.