Modelling the Mullins effect and the magnetic-dependent nonlinear viscoelasticity of isotropic soft magnetorheological elastomers

Abstract

Soft magnetorheological elastomers (s-MRE) are a smart material mainly prepared by filling soft magnetic particles into an elastomeric matrix. Under the influence of a magnetic field, the mechanical properties of the material can be changed rapidly and reversibly, offering a broad application prospect in vibration control, magnetic actuation and other areas. Due to the embedding of the magnetic particles, an obvious stress-softening phenomenon (Mullins effect) and magnetic-dependent nonlinear viscoelasticity are exhibited for the s-MRE. Recent theoretical studies mainly focused on modelling the magnetostriction and the magnetic-dependent hyperelastic behaviour of s-MRE, while less attention is paid to modelling its magnetic-dependent inelastic behaviour. However, the stress-softening and the magnetic-dependent nonlinear viscoelastic behaviour play a vital role in the application of s-MRE. In order to predict the magneto-mechanical coupling behaviour of s-MRE accurately, a constitutive model which incorporates the Mullins effect and the magnetic-dependent nonlinear viscoelastic behaviour of isotropic s-MRE is proposed. The comparison between the simulation and experimental results indicates that the residual strain, magnetic-dependent Mullins effect and nonlinear viscoelastic behaviour of isotropic s-MRE are well depicted by the model. The developed model provides a theoretical basis for the design and application of isotropic s-MRE in vibration control, magnetic drive and other fields and promotes its potential application.