Monotonic tensile behavior analysis of three-dimensional needle-punched woven C/SiC composites by acoustic emission

作     者：Peng Fang Laifei Cheng Litong Zhang Jingjiang Nie 

作者机构：National Key Laboratory of Thcrmostrucmre Composite Materials Northwestern Polytechnical University Xi＇an Shaanxi 710072 China 

出 版 物：《Journal of University of Science and Technology Beijing》 (北京科技大学学报（英文版）)

年 卷 期：2008年第15卷第3期

页      面：302-306页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：the National Natural Science Foundation of China(No.90405015) the National Young Elitist Foundation of China(No.50425208) the Doctorate Foundation of Northwestern Polytechnical University(No.CX200406) 

主　　题：C/SiC composites tensile behavior damage damage mechanism acoustic emission 

摘      要：High toughness and reliable three-dimensional needled C/SiC composites were fabricated by chemical vapor infiltration （CVI）. An approach to analyze the tensile behaviors at room temperature and the damage accumulation of the composites by means of acoustic emission was researched. Also the fracture morphology was examined by S-4700 SEM after tensile tests to prove the damage mechanism. The results indicate that the cumulative energy of acoustic emission （AE） signals can be used to monitor and evaluate the damage evolution in ceramic-matrix composites. The initiation of room-temperature tensile damage in C/SiC composites occurred with the growth of micro-cracks in the matrix at the stress level about 40% of the ultimate fracture stress. The level 70% of the fracture stress could be defined as the critical damage strength.