纤维增强聚合物基复合材料的疲劳损伤模型

从微观离散分子力学出发,考虑力学化学的交互作用和材料微观组织的影响,建立了纤维增强聚合物基复合材料的力学化学分子链疲劳损伤模型在模型中引入表示基体树脂和界面分子链断裂数占材料分子链总数的比例Am和Al来描述基体断裂主导和界面断裂主导的损伤,给出剩余强度与疲劳过程中微观断裂机理、结构参数、物理化学参数和力学性能变化之间的关系与短玻璃纤维增强树脂基复合材料(SMC)的恒载荷疲劳实验结果比较,本模型预测的疲劳剩余强度与实验值吻合得比较好,

Mechano-chemical molecular chains model of fatigue damage for fibre-reinforced polymeric matrix composites

Under the cyclic loading, the important damage characteristic of fibre-reinforced polymeric matrix composites is the damage behaviour depending on both the material microstructure and the chemical effect. Focusing on this characteristic, mechano-chemical molecular chains model for studying fatigue damage was established. The fractions of broken molecular chains in matrix and on interface were introduced respectively to describe the matrix-dominated damage or interface-dominated damage mechamism. The mechano-chemical effect was included in molecular scale and the influence of microstructure on fatigue process was considered. The relations between residual strength and mechanical properties, microstructure parameters, physical chemistry parameters were analyzed as well. Load-constant fatigue tests for composite material (SMC) were carried out, and the experimental results appeared good agreement with predicted values based on the proposed model.