Tensile and interfacial properties of SiC/SiC minicomposites

Ozawa, Kazumi; Nozawa, Takashi; Tanigawa, Hiroyasu

A silicon carbide (SiC) matrix composite is a promising candidate for nuclear fusion energy applications. In order to design a damage tolerant composite, fiber/matrix interfacial properties with and without irradiation effects should be thoroughly and systematically understood. For this purpose an approach using model composites is considered to be suitable. This study examines the effects of different fibers and interphases on tensile and interfacial properties of non-irradiated SiC/SiC minicomposites which have high crystalline and near stoichiometric SiC fibers. As a result of the tensile unloading-reloading cyclic tests, following analysis of the hysteresis loops, and the single fiber push-out tests, (1) fiber surface roughness can significantly affect interfacial sliding stress and hence each tensile characteristic such as tensile strength/strain and hysteresis loop width, and (2) interphase thickness would also influence the interfacial and tensile properties.