Experimental investigation on interlaminar and in-plane shear damage evolution of 2D C/SiC composites using acoustic emission and X-ray computed microtomography

Abstract

Carbon fiber-reinforced silicon carbide composites (C/SiC) are widely used in lightweight aerospace structures for thermal protection due to its excellent mechanical properties. The low interfacial shear strength of the composites decreases its performance and limits its application. To investigate the shearing performance of C/SiC composite, interlaminar shear and in-plane shear tests were conducted. Real-time X-ray micro-computed tomography (XCT) non-destructive testing technology is an effective method for damage analysis of composite materials. The damage mechanisms of 2D plain weave C/SiC composites prepared by chemical vapor infiltration process under interlaminar shear loading are investigated using the combination of XCT and acoustic emission detection system. The in-situ XCT results reveal the damage visualization mechanisms of the composites and the damage evolution process including matrix damage, interfacial debonding and fiber fracture. The failure mechanisms and morphology of the shear effect for 2D plain weave C/SiC were analysed.