基于微观力学失效理论的CFRP多向层合板低速冲击行为预测

基于微观力学失效(MMF)理论对碳纤维增强复合材料(CFRP)多向层合板在低速冲击载荷下失效机制及损伤过程进行分析和预测。建立基于MMF理论的层合板结构冲击损伤行为分析方法。首先, 使用MMF理论对冲击过程中组分的失效类别进行判别; 然后, 根据组分失效的类别制定出相应的材料性能退化方案来实现对复合材料在低速冲击下的逐步失效分析;在ABAQUS平台上开发了基于显示分析的用户材料子程序(VUMAT), 即基于MMF理论的层合板冲击损伤分析程序;最后, 利用MMF理论冲击损伤行为分析方法, 对UTS50/E51碳纤维增强复合材料多向层合板在小能量低速冲击情况下的失效机制和损伤形貌进行预测, 并将预测结果与试验结果进行对比, 分析了利用MMF理论预测冲击损伤这一方法的准确性。结果表明理论预测的凹坑直径与试验测试的凹坑直径误差为4.8%, 预测的失效机制和损伤形貌与实际观察的一致。 

Prediction of low-velocity impact behavior of multi-dircetional CFRP laminates based on micro-mechanics failure theory

We deal with analysis and prediction of the failure mechanism and the damage procedure of the multi-di-rectional carbon fiber reinforced plastics (CFRP)laminates under the condition of low velocity impact with small en-ergy based on the micro-mechanics of failure (MMF)theory.The impact damage behavior analysis method for the laminated structure was established based on MMF theory.During the process of impact loading,the constituent failure categories can be identified first by the MMF theory,then the comesponding material properties degradation scheme was applied to analyze the progressive failure of composites based on the constituent failure categories.De-veloped the user-defined material subroutine based on explicit analysis (VUMAT )on the ABAQUS,it is a impact damage analysis program of laminate based on MMF theory.Finally,under the condition of low velocity impact with small energy,the failure mechanism and damage appearance of the multi-directional CFRP laminates was predicted based on impact damage behavior analysis method of MMF theory.The failure mechanisms and damage appearance obtained from both predicted results and test were compared,then the accuracy of the impact damage prediction method based on MMF theory were analyzed.The results show that the error between predicted pit diameter and test pit diameter is 4.8%,the predicted failure mechanism and damage appearance are consistent with the actual analysis.