低速冲击后复合材料层合板的压缩破坏行为
COMPRESSIVE FAILURE BEHAVIOR OF COMPOSITE LAMINATES AFTER LOW VELOCITY IMPACT
-
摘要: 对缝纫层合板和无缝纫层合板进行低速冲击后压缩破坏实验,以研究低速冲击后层合板的压缩破坏机理。采用C扫描、X射线、热揭层等技术对层合板内的损伤进行测量和对比。结果表明,界面不是很强的碳纤维增强复合材料层合板低速冲击后受压时,层合板非冲击面的子层屈曲及其扩展是导致层合板冲击后压缩强度下降的重要因素,而且子层屈曲主要是沿垂直载荷的方向(90°)扩展;对于准各向同性板,屈曲子层中与母层相邻的铺层的方向一般为90°。层合板的剩余压缩强度与板的冲击损伤面积无直接关系。Abstract: Compressive failure tests were carried out on composite laminates and stitched laminates after low velocity impact to study compressive failure mechanisms of laminates after low velocity impact. Methods of X-ray, C-scan, deply, etc were used to measure and to record the internal and external damage of the laminates. The implications of this study were that sub-laminate buckling and the delamination expending were the important factors causing large reductions in strength while CFRP laminates were compressed after low velocity impact if the interface properties were not very fine. And the buckling area expended mainly in the direction perpendicular to the compressive load. For quasi-isotropic composite laminates, the orientation of the ply in buckled sub-laminate next to parent medium was generally 90°. There was no direct relation between residual compressive strength and impact damage area.