基于临界平面法的复合材料多轴疲劳损伤参量研究

Multiaxial Fatigue Damage Parameter for Fibre-Reinforced Composites Based on a Critical Plane Approach

基于临界平面方法,提出一种用于纤维增强复合材料的多轴疲劳损伤参量,研究了复合材料多轴疲劳损伤特征.同时设计出一种缠绕复合材料管状试样,进行了拉扭双轴疲劳实验研究.根据双轴载荷条件下管状试样的应力-应变分析及双轴疲劳实验结果,绘制出了基于临界平面的多轴损伤参量与疲劳寿命关系图,可对不同缠绕角的复合材料疲劳寿命进行预测.结果表明:与传统的应力-寿命预测曲线相比较,新的疲劳损伤参量更适合于复合材料的多轴疲劳研究,计算结果与实验结果吻合较好.

A multiaxial fatigue damage parameter for fibre-reinforced composite was presented based on critical plane approach and the multiaxial fatigue damage characteristics of composite were investigated. Using newly developed filament-wound composite tubular specimens, the tension-torsion biaxial loading fatigue tests were performed. The damage parameter versus fatigue life figures, which were plotted based on the stress-strain analysis and test results, could be used to predict the fatigue lives of the composite with different winding angles. It shows that the damage parameter is more suitable for composite multiaxial fatigue investigation than the traditional strain versus life curve and the predicted fatigue lives have a good agreement with the tested values.