拉-拉循环荷载作用下的界面脱粘研究

Investigation of Interfacial Debonding Under Tension-Tension Cyclic Loading

应用弹性力学和断裂力学基本理论 ,基于剪滞模型 ,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疲劳脱粘特性。建立了描述疲劳裂纹扩展的等效Paris公式 ,得到了界面疲劳脱粘扩展速率、脱粘应力以及脱粘界面的摩擦系数与循环加载次数的关系式。通过数值模拟计算 ,进一步分析了界面疲劳脱粘的力学机理。本文分析 ,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 ,同时还考虑了材料泊松比的影响。

According to elastic mechanics and fracture mechanics, based on the shear-lag model, an interfacial fatigue debonding property of fiber-reinforced composites under tension-tension cyclic loading is studied. An equivalent Paris formula is established to describe the crack growth. A relationship among the rate of the interfacial fatigue crack growth, the debonding stress, the interfacial coefficient of friction and the number of cyclic loading is obtained. By numerical simulating computing, mechanical mechanism for interfacial fatigue debonding is analyzed further. In this paper, the degradation of the debonded interface and the non-uniformity of the degradation caused by fatigue loading are considered, and the effect of the Poisson's contraction is considered too.