三维四向编织复合材料等效热特性数值分析和试验研究

 采用“米”字型枝状胞体有限元模型和试验方法对三维四向编织复合材料的整体等效热膨胀系数和等效热传导系数进行了分析并将计算结果和试验值进行了比较。研究表明枝状胞体模型能较为真实的反映三维四向编织复合材料的结构构形;有限元方法在分析热膨胀、热传导方面具有较好的精度;三维四向编织复合材料编织方向的热膨胀系数随着纤维体积比的增加而减小,随着编织角的增加而减小;热传导系数随着纤维体积比的增加而增大,随着编织角的增大而增大。

THERMAL PROPERTY OF 3-D BRAIDED FIBER COMPOSITES: EXPERIMENTAL AND NUMERICAL RESULTS

By using Fiber Hexprismyarn Diagonal Brick Cell(FHDBC) and experimental methods, the thermal expansion and conductivity of 3 D braided fiber composites were investigated and the results were compared with those from tests. The investigation shows that FHDBC can reflect the real structure of 3 D braided fiber composites. The geometric models and boundary conditions of the unit cell can be conveniently simulated by FEM. The effective thermal expansion in the braided cross sectional area decreases as fiber volume fractions and braided angle increase; the effective thermal conductivity in the braided cross sectional area increase as fiber volume fractions and braided angle increase.