三维编织复合材料面内刚度和强度性能研究

A STUDY ON IN PLANE STIFFNESS AND STRENGTH OF THREE DIMENSIONALLY BRAIDED COMPOSITES

以修正的经典层合板理论为基础，分析三维编织复合材料的力学性能。在单胞的长度方向积分和平均，预测编织结构复合材料的有效弹性模量；采用蔡－胡多项式失效准则，得到三维编织复合材料的强度性能。另外，进行编织结构复合材料的力学性能实验，探讨纺织工艺参数，如纤维编织角、横向编织角、轴向纱数与编织纱数之比、纤维体积含量等对力学性能的影响，理论预报和试验结果进行对比，发现该力学模型能较好地预报三维编织复合材料的刚度和强度性能。

Based on modified classical laminated theory, the mechanical properties of three dimensionally braided composite materials were analyzed in this paper. Carrying out the integration and averaging of compliances yields, the effective elastic modulus of braided structural composites was predicted. Tsai Wu polynomial criterion was adopted and the strengths of 3 D braided composites were obtained. In addition, the mechanical experiments of braided structural composite materials were carried out. The effects of textile process parameters, such as braider angle, transverse angle, ratio of axial yarns number to braider yarns number and fiber volume fraction on mechanical properties were investigated. A comparison between theoretical and experimental results shows that the mechanical model can reasonably predict the stiffness and strength of 3 D braided composite materials.