二维C/SiC复合材料在冲击拉伸下的损伤过程

Fracture damage of two dimensional C/SiC composites under dynamic loading

利用分离式霍普金森拉杆实验装置(SHTB)和超高速照相机,对二维C/SiC复合材料进行了冲击拉伸力学性能实验研究,同时结合其宏观力学行为,分析了在冲击拉伸载荷作用下的损伤破坏过程。结果表明:材料的应力-应变曲线呈明显的非线性特征,其内部损伤破坏和裂纹扩展过程分为四个阶段:损伤积累于第一阶段,裂纹起源于第二阶段,屈服失效于第三个阶段,快速扩展于第四个阶段。

The dynamic tensile properties of 2D C/SiC composites were investigated by means of Split Hopkinson Tensile Bar（SHTB）and ultra high-speed camera.Based on its macro mechanic behavior,the failure process of the specimen under dynamic tensile loading was analyzed.The experimental results indicate that the stress-strain curve is obviously non-linear,and examination of the failure process of the specimen helps define the four phases of crack propagation,namely,the damage accumulation phase,crack initiation phase,yield failure phase and crack fast spreading phase.