短纤维增强橡胶密封复合材料界面疲劳损伤行为

依据广义自洽方法,建立了包含芳纶纤维、界面相、橡胶基体和等效介质的代表性体积单元(RVE)模型。采用自定义材料子程序对内聚力疲劳累积损伤模型进行编译,分别在基体/界面相的界面和纤维/界面相的界面设置内聚力单元,研究界面相性能参数对纤维增强橡胶密封复合材料(SFRC)界面疲劳损伤行为的影响。探讨了界面相厚度和模量的确定方法,获得了不同界面相厚度和模量下SFRC界面脱粘起始位置以及脱粘起始疲劳次数。结果表明,较低的界面相模量能够抑制界面脱粘的产生;随着界面相厚度的增加,界面脱粘的起始疲劳次数增加,SFRC抗疲劳损伤能力得到提高。

Interfacial Fatigue Damage Behavior of Short Fiber Reinforced Rubber Sealing Composites

The representative volume element(RVE)model composed of aramid fibers,interphase,rubber matrix and equivalent medium was established based on generalized self-consistent method.The self-defined material subroutine(UMAT)was used to compile the cohesive fatigue cumulative damage model.The cohesive elements were set respectively at matrix/interphase(MI)interface and fiber/interphase(FI)interface.The influence of interphase performance parameters on the interfacial fatigue damage behavior of SFRC was studied.The method to determine the thickness and modulus of interphase was investigated.The initial position of the interfacial debonding and the corresponding fatigue number of SFRC were obtained with different interfacial thickness and modulus.The results show that the interfacial debonding of SFRC will be restrained with lower interphase modulus,and the initial fatigue numbers of interfacial debonding of SFRC increase with the increase of interphase thickness.Therefore,the ability to resist the fatigue damage of SFRC can also be improved by increasing the interphase thickness.