波形碳纳米管增强复合材料的有效刚度和局部应力的宏微观均质化数值模拟

NUMERICAL SIMULATION OF EFFECTIVE STIFFNESS AND LOCAL STRESSES FOR WAVY NANO-TUBE REINFORCED COMPOSITES BY THE MACRO-MICROSCOPICHOMOGENIZATION METHOD

采用分子动力学方法简化的碳纳米管等效纤维模型,利用具有精确周期性边界条件的均质化理论和宏微观均质化法分析正弦波形非连续碳纳米管的有效刚度和局部应力分布规律。结果表明,纳米增强复合材料的有效刚度和局部应力对碳纳米管的波形非常敏感,碳纳米管稍有弯曲就会导致复合材料有效刚度降低和应力传递能力的下降,为揭示复合材料中碳纳米管的增强机制和改善增强效果提供理论依据。

The effective elastic properties and local stress of non-continuous wavy Carbon nano-tubes （ CNTs）/polymer composites were analyzed by using the homogenization method with exact periodic boundary conditions. The effective fiber model with transversely isotropic constitutive relationships was utilized to simplify the CNT and the surrounding polymer in this study. The results show that the elastic properties and local stress are sensitive to CNTs arrays and CNTs＇ s waviness within the selected representative volume element （RVE）, and even slight change in nano-tube curvature significantly reduces the effective stiffness and the ablity of stress transfer for nano-tube reinforced composites compared with the straight nano-tubes reinforced composites, which helps to disclose the strengthening mechanism of wavy nano-tube composites and to improve the strengthening effect.