单向纤维增强陶瓷基复合材料界面滑移规律

Interface slip distribution of unidirectional fiber-reinforced ceramic matrix composites

建立了分析单向纤维增强陶瓷基复合材料力学特性的界面摩擦模型。采用基体应变能准则对基体损伤状态进行预测;由Weibull分布模型拟合出纤维断裂分数;将界面磨损处理为纤维/基体相对滑移历程的函数τi=τi(Δδ),很好地表征了不同位置纤维/基体相对滑移历程不同所引起的界面磨损程度的区别。运用该模型分析了准静态加载和拉-拉循环载荷下的应力-应变特性,预测结果与实验数据吻合较好。最后采用此模型研究了任意载荷历程下界面的滑移规律。

An interfacial friction model has been presented to analysis the mechanical behavior of unidirectional fiber reinforced ceramic matrix composites. The matrix crack spacing was determined by means of the critical matrix strain energy criterion; the percentage of fractured fibers was determined via a unique Weibull failure distribution; the extent of interface wear has been estimated as a function of the relative displacement between fiber and matrix, Ti=Ti（△δ）. The stress- strain responses under quasi-static and cyclic loading obtained from the present analytical model are in a good agreement with their experimental counterparts. The interface slip distribution under a random load course has been discussed.