Finite deformation analysis of isotropic magnetoactive elastomers

In this study, the large deformation analysis of the magnetoactive elastomers based on continuum mechanics approach has been conducted. First, the governing differential equations for the spatial configuration are presented. Stored energy density function defined with respect to the invariants of the right or left Cauchy–Green deformation tensor and the magnetic field induction vector is adopted to develop a material model for finite deformation of isotropic magnetoactive elastomers (MAEs). An isotropic magnetoactive sample with 15% iron particle volume fraction is then fabricated, and a test setup has been designed to measure its magnetic permeability. Using an advanced magnetorheometer, quasi-static tests are then carried out on MAE circular cylindrical samples to find their torque-twist response under various magnetic fields. The experimental results are then effectively utilized to identify the unknown parameters in the proposed material model. The accuracy of the proposed constitutive model in predicting the response behavior of the MAE is then demonstrated through comparison of theoretical results with those obtained experimentally.