三维机织陶瓷基复合材料的面内剪切性能及损伤研究

Mechanical Properties and Damage Process of a Three-dimensional Woven Ceramic Composite under In-plane Shear Loading

采用IOSIPESCU纯剪切试件,考虑纤维的编织结构和失效机理,研究了三维机织碳／碳化硅(C／SiC)复合材料在面内剪切载荷作用下的力学性能和损伤过程．材料具有明显的非线性应力-应变行为和残余变形等特性．材料主要的损伤机制为基体微裂纹开裂,界面脱粘和纤维断裂,其中界面裂纹是材料应力-应变等力学行为的主要影响因素．基于连续介质损伤力学分析方法,提出了简单的损伤演化模型并对损伤演化过程进行了描述．

The mechanical behavior and damage process of a three-dimensional woven carbon/silicon carbide （C/SiC） composite under inoplane shear loading were investigated With IOSIPESCU specimens in relation with the failure mechanisms and the fiber architecture. The C/SiC composite exhibited several interesting features including an essentially non-linear stress-strain behavior and permanent deformations. The results show that the major damage mechanisms are matrix microcracks cracking, interface debonding and fiber breaking. The delamination cracks affect mainly the stress-strain behavior and the mechanical properties. A damage model is proposed based upon continuum damage mechanics to describe the damage evolution.