冲头几何形态对复合材料层合板低速冲击损伤特性的影响
The Influence of Punch Geometry on the Low-Velocity Impact Damage Characteristics of Composite Laminates

本文通过ABAQUS软件对不同结构形状的冲头对T300/PA6复合材料层合板的冲击损伤进行了仿真研究。在全方位考虑层合板中基体失效、纤维失效、层间失效及其混合失效等多种失效模式的基础上，运用VUMAT子程序构建三维Hashin失效判据，并采用内聚力单元模型深入分析了层合板层间损伤的逐步演变过程。研究结果显示，圆柱形冲头接触时长最短，为3.9 ms，分层面积最大，为1841.34 mm²；圆锥形冲头接触时长最长，为6.6 ms，分层面积为553.11 mm²，其表明设计较钝的冲头会带来更大的冲击力和更短的接触时长，会进一步导致分层损伤的产生；与此相对，更尖锐的冲头会带来更小的冲击并延长其接触时长，对于基体损伤的产生更为有利。在冲击能量保持恒定的前提下，使用较钝的冲头设计对层合板造成的损害相对较轻。
In this study, the impact damage of T300/PA6 composite laminates subjected to punches with different structural shapes was investigated through numerical simulations using the ABAQUS software. On the basis of all-round consideration of various failure modes in the laminates, including matrix failure, fiber failure, interlaminar failure, and failure of their combinations, a three-dimensional Hashin failure criterion was established using the VUMAT subroutine. Cohesive zone elements were employed to thoroughly analyze the progressive evolution of interlaminar damage in the laminates. The results show that the cylindrical punch has the shortest contact duration of 3.9 ms and the largest delamination area of 1841.34 mm². In contrast, the conical punch has the longest contact duration of 6.6 ms and a delamination area of 553.11 mm². This indicates that a more blunt punch design leads to higher impact forces and shorter contact durations, which in turn promotes delamination damage. Conversely, a sharper punch results in lower impact forces and extended contact durations, which is more conducive to matrix damage. When the impact energy is kept constant, a blunter punch design causes relatively less damage to the composite laminates.