【摘要】 从真实反映制造工艺对2.5维机织复合材料厚度方向上纱线束截面尺寸的影响出发，在传统二元分胞模型基础上提出了一种新的胞体—过渡胞，进而在细观尺度上建立了2.5维机织复合材料三胞体模型（TCM）。该模型反映了不同厚度位置经纱几何参数的差异，弥补了传统分胞方法的不足。基于TCM和刚度体积平均方法预测了几种典型2.5维机织复合材料包括弹性模量在内的力学性能，并与实验结果进行了对比。分析结果表明，基于TCM的预测结果相比传统模型预测精度更高；另外，经向弹性模量在厚度方向上呈现“马鞍”形分布；对10-6w材料，过渡单胞和内层单胞的经向弹性模量相差约6%，而传统分胞方法无法准确反映材料表层/次外层和内层材料结构及力学性能的差异。更多还原

【Abstract】 For the purpose of taking the impact of manufacturing procedure on the cross-section of fiber bundles along thickness direction into account,a Ternary-Cell microscopic model(TCM)for 2.5 dimensional(2.5-D)woven composites was proposed by introducing a new type of RVE(transition cell)into traditional cell partition method.Compared with conventional models,the ternary cell model is capable of capturing the differences of geometrical parameters of surficial,sub-surficial,and internal fiber yarns.Moreover,mechanical parameters including Moduli of several types of typical 2.5-D woven composites were predicted based on TCM as well as stiffness matrix average method.The results showed that the predictions agreed well with experimental data;in addition,a characteristic“saddle-shape”curve was observed for longitudinal tensile modulus along thickness direction;and for 10-6w,the comparative error of longitudinal tensile stiffness between surface cell,transition cell,and inner cell was around 6%,which indicated the deficiency of traditional cell partition method.更多还原