三维四向编织复合材料弯曲性能的预测

Prediction of the bending properties of three-dimensional four-directional braided composites

基于经典层合板理论和叠层板模型,提出了一种预测三维四向编织复合材料弯曲性能的方法.在叠层板模型中,代表性体积单元的厚度为编织复合材料的整体厚度,宽度为一个编织花节宽度,长度为一个编织花节长度,并简化为具有不同材料主方向的单向层板的叠合结构.不同层板间的交叉重叠按各层板性能的体积平均进行简化,同时假设代表性体积单元具有均匀的中面应变和曲率.此外,模型中考虑了编织纱线的排列方式以及表面纱线的影响.理论分析结果与实验值吻合较好.

This paper describes a methodology for predicting the bending properties of threedimensional fourdirectional braided composites based upon the classical laminated plate theory and the laminated plate model. In this model, a representative volume element is defined by the total thickness of composites, the braiding wide and the braiding pitch are simplified as an assemblage of inclined unidirectional laminae with differential local axis coordinate system. The intercrossing influence between the laminae is simplified by the volume averaged properties of each lamina. And the strain and curvature of the volume element geometrical midplane is assumed to be uniform. In addition, the influence of the braiding yarn pattern and the surface yarn is also included in the analysis. Finally, comparisons between predictions and experimental data are also presented.