Fabrication of short C fiber-reinforced SiC composites by spark plasma sintering

Short carbon fiber reinforced SiC matrix composites were fabricated by spark plasma sintering. Density and mechanical properties of the composites increased continuously at increasing sintering temperature and constant pressure. Cracks in the composite matrix resulted from high thermal residual stresses generated during the cooling process from the sintering temperature due to the thermal expansion coefficient mismatch between fiber and matrix. The properties of the composites were lower than those of monolithic SiC ceramics obtained with the same processing technique as the composites. Fibers provided noncatastrophic fracture behavior of the composites as evidenced by the stress-displacement curves and fracture surface of the composites.