Microstructural characteristics of short carbon fiber reinforced pitch-based carbon/carbon composites

Short carbon fiber reinforced pitch-based carbon/carbon composites (SCFRC) with high density and low cost were fabricated under atmospheric conditions by a new and efficient mould pressing and semi-carbonization shaping technology. Microstructures and fracture morphologies of the SCFRC materials were observed using optical microscopy and SEM. The damage formation mechanism of short carbon fibers in mould pressing SCFRC materials was investigated, and an interface structural model between reinforcements (such as short carbon fiber and granular cokes) and carbon matrix in SCFRC materials was also proposed. Moreover, the findings indicate that both a matrix phase and a particle phase exist in SCFRC materials, and the particle phase is enwrapped by the matrix phase which has a layered structure like multiple orange peels. The orange-peel structure is similar to the parallel-oriented graphite structure on the surface of some carbon fibers.