基于改进Hashin准则的复合材料低速冲击损伤研究

Low-velocity impact analysis of composite plates based on modified Hashin criterion

针对复合材料力学性能的分散性和传统模型中退化系数选取的随意性问题,将退化系数与复合材料强度的威布尔分布参数相结合,采用改进的三维Hashin准则建立了复合材料低速冲击渐进损伤模型。考虑复合材料非线性剪切行为改进了Hashin准则,将原始准则中的剪切项用应变能替代,并采用最大应变准则判断剪切失效,避免了应力准则导致的变形不连续。采用该模型对三种能量下的T300/3501复合材料层合板低速冲击过程进行了仿真分析,计算得到的冲击响应曲线、层内和层间分层损伤结果与实验结果吻合良好,表明建立的模型适用于复合材料层合板低速冲击损伤预测。

A progressive damage model based on a 3D modified Hashin criterion was proposed to simulate the composite plates subjected to low-velocity impacts. Considering the dispersion of the composite strength,the degradation parameters related to the Weibull distribution of the composite strength were used in this model. Meanwhile,the degradation parameters' arbitrarily chosen problem was avoided. Composite nonlinear shear behavior was considered in a modified Hashin criterion. The shear terms in the original criteria were replaced by a strain energy form; meanwhile,the composite shear failure was predicted by maximum strain criterion. Therefore,the discontinuous deformation caused by the stress criterion could be prevented. Low-velocity impacts of T300 /3501 composite plates under different energies were simulated using this model. The impact response curves and the intra- and inter-laminar damage obtained from the numerical analyses were comparable with test results. It is shown that the proposed model can effectively predict the lowvelocity impact damage of composite plates.