Improvement of the strength and toughness of carbon fiber/SiC composites via chemical vapor infiltration-grown SiC nanowire interphases

Abstract SiC nanowires (SiC nws ) were used to modify the interphase of carbon fiber/pyrocarbon/SiC(C f /PyC/SiC) composites. These SiC nws were grown in the carbon fiber preform via chemical vapor infiltration(CVI). The effects of these SiC nw interphases on the microstructure and mechanical properties of C f /PyC/SiC composites were investigated. According to the obtained results, the composites containing SiC nw interphases(i.e., C f /SiC nw /PyC/SiC and C f /SiC nw /SiC) showed higher strength and toughness than C f /PyC/SiC composites at both room and high temperatures. The superior pull-out and bridging crack characteristics of SiC nws can account for the toughening of C f /SiC and C f /PyC/SiC upon growth of SiC nw interphases, which resulted in composites with higher crack propagation resistances and superior load with standing capabilities.