缝合复合材料弹性性能的三维有限元细观分析与试验验证

Finite Element Micromechanical Analysis and Experimental Confirmation of the Elastic Properties of Stitched Composite Materials

建立了缝合复合材料代表单元体的三维有限元模型,模型中考虑了缝线的实际形状,以及缝线与层合板之间的位置关系,并把层合板的每层视为有一定厚度的体,全面考虑缝合层板在3个方向上的性能。模型所取的单元体为全厚度方向,相对实际细观结构简化较少,分析结果与试验数据的比较表明,分析模型所得的结果可信,可以用于工程设计,为缝合复合材料的分析和减少试验件提供了理论分析方法。

The reinforcement of polymer matrix composites by through-the-thickness stitching is a promising technique for raising the damage tolerance of laminar structure. A three-dimensional finite element micromechanical modeling approach is proposed for predicting the macro-elasticity constants of stitched/RTM CFRP composites. The actual shape of stitching yarn and the position between yarns and laminate are taken into account. The unit cell of the model is picked up from entire thickness of stitched laminate. Each lamina is taken as a body but not a panel and the elastic constants are calculated in three directions. As fewer hypotheses are taken, the analytical result is more precise. Comparing the relevant predictions with the experimental results validates the presented model.