中文摘要：

为了研究三维四步法编织复合材料的力学性能,利用ANSYS有限元软件对材料的细观体胞模型进行数值模拟,计算三维编织复合材料的宏观弹性常数,讨论了纤维编织角和体积比对弹性常数的影响。采用不同的强度准则分别对纤维束和基体材料进行强度校核,从而得到材料发生破坏时失效单元的体积百分比。根据失效单元的分布情况分析材料的破坏机理,进而预报材料的拉伸强度。模拟计算结果与实验值吻合较好。

英文摘要：

To study the mechanical properties of four-step 3D braided composites,a basic cell model of braided composites was simulated by FEA software ANSYS.Macroscopic elastic constants of 3D braided composites were calculated,and the effects of the braiding angle and the fiber volume ratio on the elastic constants of the materials were discussed.Different criteria for the strength of yarns and the matrix were used to get the ratio of damaged element volume to the whole volume when the material failure occurs.According to the distribution of the damaged elements,the failure mechanism of braided composites was analyzed,and the tensile strength of the materials was predicted.The simulation results agree quite well with the experimental results.