Mechanical Properties of Unidirectionally Reinforced Carbon-SiC Composite Fabricated by Hot Press Sintering Method (2)

SiC composites (Cf/SiC) reinforced with unidirectionally oriented carbon fibers are fabricated by Hot press sintering method. Five kinds of carbon fibers are used for the reinforcement. Tensile strengths of carbon mono-filaments after filament winding (FW) treatment, press treatment and heat treatment are measured to estimate the damages of them under the Cf/SiC fabrication. The mechanical properties of Cf/SiC composites are classified by two groups. One group shows high fracture toughness (13.4 - 21.4 MPa√m) and high flexural strength (360-540 MPa) and the other group shows low fracture toughness (3.4-6.3 MPa√m) and low flexural strengh (240-290 MPa). From tensile strength measurments of carbon mono-filament, it is turned out that two kinds of carbon fibers are easily deteriorated by (FW treatment)+(Press treatment)+(Heat treatment), and Cf/SiC composites fabricated by the fibers shows low fracture toughness and low flexural strength.