开孔碳纤维复合材料层合板的拉伸失效有限元分析

基于ABAQUS有限元软件中的二维壳单元和三维实体单元，对铺层角度为［0°/(±45°)₃/(90°)₃］_s的开孔T300/1034-C碳纤维复合材料层合板在拉伸载荷作用下的失效过程进行研究.首先，在ABAQUS有限元软件中建立壳单元和连续壳单元碳纤维复合材料模型，利用自带的2D Hashin准则与退化模型模拟了层内失效.但二维模型没有考虑各层失效间的相互影响，进而通过编写材料子程序VUMAT，引入3D Hashin准则和基于断裂能的等效应力-应变双线性退化方式，采用实体单元模拟碳纤维复合材料的失效行为.通过对三种单元模型进行模拟，结果表明:开孔造成的应力集中会使层合板在拉伸过程中纤维与基体更易失效，成为裂纹源;在层合板失效过程中，都呈现“X形”向“沙漏形”失效发展趋势，最终沿宽度方向断裂;实体模型模拟精度相比于传统壳单元、连续壳单元的偏高更接近实验数值，三种单元模拟极限失效载荷与实验数据相差分别为26.1%，31.1%，8.64%.

Finite Element Analysis of Tensile Failure of Open-Pored Carbon Fiber Composite Laminates

The failure process of the open-pored T300/1034-C carbon fiber composite laminate with a ply angle of ［0°/(±45°)₃/(90°)₃］_s under tensile load was studied by using 2-D shell elements and 3-D solid elements in the ABAQUS finite element software. First， the shell element and continuous shell element carbon fiber composite material models were established with the ABAQUS finite element software， and the internal failure of the layer was simulated using the built-in 2-D Hashin criterion and degradation model. However， the 2-D model did not consider the interaction between the failures of each layer， and by writing the material subroutine VUMAT， the 3-D Hashin criterion and the equivalent stress-strain bilinear degradation method based on the fracture energy were introduced， and the solid element was used to simulate the carbon fiber composite material failure behavior. Through the simulation of three element models， the results showed that the stress concentration caused by the opening will make the fiber and matrix of the laminate more likely to fail during the stretching process and become the source of cracks; during the failure process of laminates， they all show a failure development trend from "X-shape" to "hourglass-shape"， and eventually break in the width direction; compared with the traditional shell element and continuous shell element， the simulation accuracy of the solid model is closer to the experimental value. The simulation limit failure loads of the three elements differ from the literature data by 26.1%， 31.1%， and 8.64%， respectively.