基于均匀化方法的三维编织复合材料等效弹性性能预测

由于三维编织复合材料具有复杂的空间拓扑结构,其力学性能分析通过宏观有限元方法往往因为占用大量的计算机内存而难以实现。从细观结构入手,计算材料的等效弹性模量可大大降低计算量。现建立了等效弹性模量的均匀化列式及有限元求解方法,运用该方法对三维编织复合材料的等效弹性性能进行了预测,并提出了三种单胞模型的周期性边界条件的施加方法。通过该方法得到等效弹性模量与实验结果较为吻合,从而有利于进行下一步的细观应力场计算。

Homogenization-Based Method for Predicting Effective Elastic Properties of Three-Dimensional Braided Composites

Due to the spatial complexity of three-dimensional structure, it is difficult to analyze the mechanical performance of three-dimensional braided composites by macro finite element method which may cost large amounts of computer memories . Studying the microstructure and calculating the effective elastic modulus of the structure can effectively solve this problem. In this paper, the homogenization formulation of the effective elastic modulus, and the schemes to solve the problem using finite element method were given. The effective elastic modulus of three-dimensional braided composites were predicted by this method. Proper periodic boundary conditions were applied for three kinds of unit cells. The calculation results of effective modulus which agree quite well with some experiment results were obtained by this method. Then the micro-stress will be expediently analyzed.