复合材料层板低速冲击损伤有限元模拟

Dynamic Simulation for Composite Laminates Damage Process due to Low Velocity Impact

利用三维动态有限元模拟计算复合材料层板的低速冲击损伤的过程．采用了基体开裂判据和分层扩展判据，分类考虑不同的损伤形式．通过修正损伤铺层材料的常数来模拟层板损伤所造成的局部刚度下降对冲击过程的影响，讨论了接触定律在冲击损伤问题中的适用性，并结合实验结果给出适于严重冲击损伤层板的卸载定理．模拟计算结果得到的低速冲击后各界面的分层损伤面积与实验结果吻合较好．

A transient dynamic three dimensional 20 point finite element analysis was presented for the simulation of the damage process of composite laminates due to low velocity impact.Two damage criterion were adopted here to computer different impact damage modes.They were damage initiation criterion for matrix cracking and delamination propagation criterion for the laminate interfaces. The influence of local stiffness degression resulted from damage on impact process was simulated through modifying the material constants of damaged layers. The contact laws were discussed, and a new general unloading law for low velocity impacted plates was developed.The delamination area of each interface was calculated. The results of the analysis were compared with the existing test data, and a good agreement was found.