高体积含量非线性黏弹复合材料有效性质

提出了一个细观力学模型,可用于预测高体积含量非线性黏弹复合材料有效性质.该模型基于广义割线模量法、双球法以及Laplace-Carson变换技术.所提出的模型对玻璃微珠填充高密度聚乙烯(GB/HDPE)复合材料的应力应变关系进行了预测,结果与文献实验结果吻合;计算结果还表明在高体积百分比下文中所提出的方法比基于MT方法预测的粘性效应明显减弱;最后还将所提方法与线黏弹框架下的均质化模型做了比较,结果表明GB/HDPE表现出明显的非线性,线黏弹本构无法描述应变率对其力学行为的影响.

NONLINEAR VISCOELASTIC EFFECTIVE BEHAVIOR FOR COMPOSITES AT FINITE PARTICLE CONCENTRATION

A micromechanical model was proposed to estimate overall nonlinear viscoelastic behavior for particulate polymer composites at finite particle concentration. The method was based on the generalized secant method, Laplace-Carson transformation technique and double-inclusions method. The stress and strain curves for glass-beads/HDPE composite were predicted, and they agree well with the experimental ones. The results also show that the proposed model predicts a significant stiffer response than the one based on Mori-Tanaka model at finite particle concentration. The proposed method was also compared with the homogenization model in a linear viscoelastic framework,the results show that GB/HDPE presents an important nonlinear viscoelastic behavior,the linear viscoelastic model fails to characterize its rate-dependent behavior.