Mechanical Properties of Unidirectionally Reinforced Carbon-SiC Composite Fabricated by Hot Press Sintering Method

SiC composites (Cf/SiC) reinforced with unidirectionally oriented carbon fibers are fabricated by hot press sintering method. Five kinds of C fibers are used for the reinforcement. Tensile strengths of C mono-filaments after filament winding (FW) treatment, press treatment, press treatment and heat treatment are measured to estimate the damage to them under the Cf/SiC fabrication. The mechanical properties of Cf/SiC composites are classified into two groups. One group shows high fracture toughness (13.4-21.4 MPa root m) and low flexural strength (240-290 MPa). From tensile strength measurements of C mono-filament, it is shown that two kinds of C fibers are easily deteriorated by (FW treatment) + (press treatment) + (heat treatment), and Cf/SiC composites fabricated by the fibers show low fracture toughness and low flexural strength.