细观结构对复合材料热膨胀系数的影响研究

基于应力为未知量的通用单胞模型改进算法在保证计算精度的前提下，可以提高计算效率，本文利用该方法计算了纤维细观结构对纤维增强复合材料热膨胀系数的影响。计算结果表明，热膨胀系数随体积比的增加而减小，纵向热膨胀系数受纤维的形状和排列方式的影响不大，而横向热膨胀系数受纤维形状以及排列方式的影响较为明显。复合材料的纵向热膨胀系数并不是随温度上升而上升的．它与各组分的弹性模量和热膨胀系数等有关．

Influence of Micro-Structual Geometry on Thermal Expansion Coefficient of Composites

An efficient implementation of the GMC micromechanics model is used to predict thermal expansion coefficients in this paper. The efficient implementation, which can be used to analyze repeating unit cells containing thousands of subcells, is more efficient than original formulation of GMC. The results indicate that the macro-thermal expansion coefficients increase with volume ratio decreasing. The influence of fiber shape and packing arrangement on transverse macro-thermal expansion coefficient is obvious, but its influence on longitudinal macro-thermal expansion coefficient is a little. The longitudinal macro-thermal expansion coefficient doesn't increase with the temperature's rising. The longitudinal macro-thermal expansion coefficient relates to each composition of composite.