缎纹编织复合材料紧固件拉拔试验及数值模拟

缎纹编织复合材料紧固件中螺牙细节尺寸已达到细观尺度量级,若在数值模拟过程中对于螺牙采用统一的材料属性,则不能准确地模拟其真实失效模式。针对此问题,建立的紧固件螺牙有限元模型是由若干层简化缎纹编织复合材料细观结构代表体积单元堆叠而成,如此模型可包含必要的纤维分区和基体分区。对螺牙模型进行拉拔试验模拟,并基于各组分材料的失效判据,实现对紧固件破坏载荷的预报。完成了缎纹编织碳/碳复合材料单螺牙紧固件拉拔试验。模拟失效模式与真实失效模式吻合良好,二者破坏载荷误差为5.17%,验证了有限元模型的合理性。

Tensile test and numerical simulation for satin weave composite fastener

Detailed sizes of threads in the satin weave composite fastener have reached the meso scale. It is not accurate to simulate the real failure mode if the uniform material is applied to the thread in the process of numerical simulation. For this problem, the finite element model of the fastener thread is established by stacking several layers of simplified satin weave composite meso-structure representative volume elements, which results in that the model includes essential fiber region and matrix region. Numerical simulation for the tensile test of thread model is carried out. Based on the failure criterion of each component material, prediction on the damage force of fastener is achieved. Tensile test for the satin weave carbon/carbon composite single thread fastener are accomplished. Good agreement between simulated failure mode and real damage mode is observed and the error of damage forces between the both methods is 5.17%, which verifies the rationality of the finite element model.