纤维增强复合材料界面疲劳裂纹扩展的模拟研究

SIMULATION OF FATIGUE CRACK GROWTH ON THE INTERFACE OF FIBER-REINFORCED COMPOSITES

脱粘是纤维增强复合材料界面裂纹扩展的主要表现形式。基于剪切筒模型和常用的实验加载方式,研究了纤维增强复合材料中纤维与基体界面在拉-拉循环荷载作用下的裂纹扩展。借助描述疲劳裂纹扩展的Paris公式,得到了疲劳裂纹扩展速率、扩展长度以及界面上摩擦系数与加载次数的关系。在分析中,考虑了疲劳加载引起的脱粘界面的损伤及损伤分布的不均匀性,同时还考虑了材料的泊松效应。

Debonding is a main form of interfacial crack growth of fiber-reinforced composites. Based on the shear-lag model and the usual loading way, the crack growth on the interface of fiber-reinforced composites under tension-tension cyclic loading is studied. According to the Paris law, the relationship between the rate of the interfacial fatigue crack growth and the number of loading cycles, the relationship between the interfacial fatigue crack growth length and the number of loading cycles, and the relationship between the interfacial coefficient of friction and the number of loading cycles are obtained. The degradation of the debonded interface and the non-uniformity of the degradation caused by fatigue loading as well as the effect of the Poisson抯 contraction are considered in the present analysis.