Mechanical Properties of SiCf/SiC Composites with Ti3SiC2 Interphase Formed by Electrophoretic Deposition Method

In this study, Ti3SiC2, a nanolayered ternary carbide, which shows superior oxidation resistance than carbon and hexagonal-boron nitride (h-BN), was selected as the interphase for SiCf/SiC composites, and Ti3SiC2 coating was formed on SiC fibers by the electrophoretic deposition (EPD) method. The SiCf/SiC composites with the Ti3SiC2 interphase with the different thickness were prepared, and the effect of the Ti3SiC2 interphase on their mechanical properties was discussed. Whereas the SiCf/SiC composites using uncoated SiC fibers showed brittle fracture behavior without fiber pullout and interfacial debonding, the SiCf/SiC composites with Ti3SiC2 interphase exhibited pseudo-ductile fracture behavior with the large amount of fiber pullout and interfacial debonding. Bending strength and fracture energy of the SiCf/SiC composites with Ti3SiC2 interphase were much higher than those of the SiCf/SiC composites without Ti3SiC2 interphase. From the results of mechanical properties of the SiCf/SiC composites with Ti3SiC2 interphase varying the thickness, it was suggested that the Ti3SiC2 interphase thickness affected their bending strength and fracture energy. It was demonstrated that Ti3SiC2 interphase was successfully formed on SiC fibers by EPD method, the SiCf/SiC composites with excellent mechanical properties were achieved by controlling the Ti3SiC2 interphase thickness, and Ti3SiC2 was effective as the interphase for SiCf/SiC composites.