A Nonlinear Magneto-Mechanical Coupled Constitutive Model for the Magnetostrictive Material Galfenol  

作　　者：Ying Xiao Haomiao Zhou Xiaofan Gou 

机构地区：[1]College of Information Engineering,China Jiliang University,Hangzhou,310018,P.R.China [2]College of Mechanics and Materials,Hohai University,Nanjing,210098,P.R.China

出　　处：《Computers, Materials & Continua》2018年第3期209-228,共20页计算机、材料和连续体（英文）

基　　金：supported by a grant of the Fund of the NationalNatural Science Foundation of China (No. 11472259);the Natural Science Foundation of Zhejiang Province (No. LR13A020002)。

摘　　要：In order to predict the performance of magnetostrictive smart material and pushits applications in engineering, it is necessary to build the constitutive relations for themagnetostrictive material Galfenol. For Galfenol rods under the action of the pre-stress andmagnetic field along the axial direction, the one-dimensional nonlinear magneto-mechanicalcoupling constitutive model is proposed based on the elastic Gibbs free energy, where theTaylor expansion of the elastic Gibbs free energy is made to obtain the polynomial forms. Andthen the constitutive relations are derived by replacing the polynomial forms with the propertranscendental functions based on the microscopic magneto-mechanical coupling mechanism.From the perspective of microscopic mechanism, the nonlinear strain related to magneticdomain rotation results in magnetostrictive strain changing with the pre-stress among theelastic strains induced by the pre-stress. By comparison, the predicted stress-strain,magnetostrictive strain, magnetic induction and magnetization curves agreed well withexperimental results under the different pre-stresses. The proposed model can describe notonly the influences of pre-stress on magnetostrictive strain and magnetization curves, butalso nonlinear magneto-mechanical coupling effect of magnetostrictive materialsystematically, such as the Young’s modulus varying with stress and magnetic field. In theproposed constitutive model, the key material constants are not chosen to obtain a good fitwith the experimental data, but aremeasured directly by experiments, such as the saturationmagnetization, saturation magnetostrictive coefficient, saturation Young’s modulus, linearmagnetic susceptibility and so on. In addition, the forms of the new constitutive relationsare simpler than the existing constitutive models. Therefore, this model could be appliedconveniently in the engineering applications.

关 键 词：Magnetostrictive materials one-dimensional constitutive relations galfenolrods nonlinear magneto-mechanical coupling 

分 类 号：O17[理学—数学]