硅橡胶基电流变弹性体的动态粘弹性及非线性本构模型

摘要

对电流变弹性体(electrorheological elastomers,EREs)的动态粘弹性及本构模型进行研究.以硅橡胶为基体,TiO2/尿素核壳颗粒为功能分散相,在1 kV/mm取向电场条件下固化,制备颗粒体积含量为30％的各同异性ERE.在不同电场强度、剪切频率、应变幅值下测试ERE的应力-应变滞回曲线,并分析各工况下ERE的动态粘弹性,得到电场强度、应变幅值、剪切频率等因素对ERE动态粘弹性的影响规律.在实验基础上,建立了基于修正Bouc-Wen模型的ERE非线性本构模型,并识别出模型参数.结果表明,该本构模型模拟结果与试验数据吻合较好,说明该模型能够准确表征材料的动态粘弹性和非线性特征.%The viscoelastic properties and the modeling of electrorheological elastomers (EREs)under harmonic loadings were presented in this paper.With a 30％ volume fraction of TiO2/urea core-shell particles dispersed in silicone rubber matrix,the anisotropic ERE samples were fabricated by curing under a constant electric field of 1 kV/mm.The samples were tested under different levels of electric field with variable shear frequencies and strain amplitudes.Then the influences of loading conditions to viscoelastic properties of ERE were analyzed.Af-ter that a revised non-linear Bouc-Wen model was used to portray the behaviors of ERE and the parameters in this model were identified based on the experimental data.The simulations agreed well with the test data,indi-cating that the revised Bouc-Wen model can effectively reproduce the viscoelastic properties and nonlinearity of EREs.