动态载荷下C/C复合材料的压缩破坏行为  

Compressive mechanical behavior of carbon/carbon composites under dynamic loading

作　　者：袁秦鲁[1] 李玉龙[1] 李贺军[2] 郭领军[2] 李淑萍[2] 

机构地区：[1]西北工业大学航空学院,陕西西安710072 [2]西北工业大学材料科学与工程学院,陕西西安710072

出　　处：《新型炭材料》2010年第2期114-118,共5页New Carbon Materials

基　　金：国家自然科学基金重大计划项目(90405016)~~

摘　　要：利用电子万能试验机以及Split Hopkinson Compressive Bar(SHPB)测试了2DC/C复合材料在准静态、动态载荷下的压缩性能,结合光学显微镜分析了其在不同应变率下的破坏形貌、讨论了应变率对压缩破坏形貌的影响。结果表明:与准静态(10-4/s)相比,动态载荷下(5×102/s)复合材料的压缩强度提高了55%,压缩刚度提高了66%,具有较强的应变率效应;在准静态载荷下,C/C复合材料沿40°角剪切破坏,断口上炭纤维破坏具有溃散及剪切破坏特征,而在动态载荷下,C/C复合材料破坏成大小不一的碎片,其炭纤维破坏具有劈裂特征。C/C复合材料破坏模式的不同可归结为基体及界面强度的应变率效应。Both quasi-static and dynamic compressive properties of 2-D carbon/carbon （C/C） composites in their thickness direction were determined using a universal test machine and Split Hopkinson Pressure Bar with pulse shapers. The compressive failure of the composite was photographed to demonstrate the failure mode at dif- ferent strain rates, and the effects of strain rate on fracture mode are discussed. Results show that the compressive stiffness and strength of the C/C composites increase with strain rate. The compressive stiffness and strength of the C/C composites under dynamic loading with a strain rate of 5 × 10^2/S are increased by about 66% and 55% respectively compared with quasi-static results with a strain rate of 10^-4/s. Under quasi-static conditions, the samples failed by shear with a shear fracture angle of approximately 40°, and carbon fiber bundles were sheared and crushed. Under dynamic conditions, the samples were broken into many fragments with different sizes, and carbon fiber bundles were fractured by splitting. The different failure modes may be related to the strain rate sensitivity of the carbon matrix and the interface strength.

关 键 词：C/C复合材料 动态压缩 应变率效应 破坏模式 

分 类 号：TB332[一般工业技术—材料科学与工程]