XIE Weijie, CHEN Mingwei, QIU Haipeng, ZHANG Bingyu, GUAN Hong, WANG Qiming
(AVIC Composite Corporation Ltd., Beijing 101300, China) 

Abstract: SiC fiber reinforced SiC matrix (SiC/SiC) composites were prepared by polymer impregnation pyrolysis (PIP) process withpolycarbosilane (PCS) as impregnant and SiC fiber as reinforcement. Based on the principle of Iosipescu shear test and the feature of SiC/SiCcomposites, the corresponding test fixture and the specimen were designed and an in-plane shear strength test method at elevated temperatures for SiC/SiC composites was established at the meantime. The influence of the sample shape size, loading rate, high temperature fixturematerials on test results and the life of test fixture was Analyzed. Eventually a more optimal in-plane shear strength test method at elevatedtemperatures for SiC/SiC composites was identified.

Key words: SiC/SiC composites; in-plane shear strength; test method