复合材料层合板低速冲击损伤的有限元模拟
Finite element simulation of low velocity impact damage on composite laminates
-
摘要: 建立了用于预测复合材料层合板在低速冲击作用下损伤的3D有限元模型。采用应变描述的失效判据来判断铺层层内的各类损伤, 如纤维断裂、 纤维挤压、 基体开裂、 基体挤裂, 并结合相应的刚度折减方案对失效单元进行刚度折减。使用界面元模拟层间区域, 结合传统的应力失效判据和断裂力学中的能量释放率准则来定义分层损伤的起始和演化规律, 提出了一种界面元损伤起始强度沿厚度方向的分布函数。通过对数值仿真结果和实验结果的比较, 验证了模型的合理性和准确性。Abstract: A 3D finite element model with cohesive was established for simulating composite laminated under transversely low velocity impact. The strain-based failure criterion of composite including fiber tensile failure, fiber compress failure, matrix crushing and matrix cracking with corresponding stiffness degradation technology, were adopted to model the in-plate damage. Cohesive elements were used for modeling the regions between two laminas. The initial and evolution of interlaminar damage was decided by a bilinear cohesive law which combines stress-based and facture-mechanics-based failure criterion. And a cohesive element initial damage strength function was introduced. A good agreement was obtained between numerical analysis and experimental results.