Adaptive dynamic moduli of magnetorheological elastomers: From experimental identification to microstructure-based modeling

Highlights: • A microstructure model has been developed for magnetorheological elastomers (MREs). • The model clarifies the relationship between microstructure and dynamic properties. • Relaxation times depend on the magnetic field and on particles' content and distribution. • The model accurately predicts the storage/loss moduli of isotropic and anisotropic MREs. In this study a dynamic physic-based model considering the microstructure of isotropic and anisotropic MREs is developed to accurately predict their field-dependent viscoelastic properties. A cubic network in which magnetic particles are located at the junctures and connected with elastic springs is utilized to derive the dynamic governing equations of motion of particles to evaluate their relaxation spectrum while moving parallel and normal to the field direction. A dipole magnetic saturation model is subsequently implemented to derive the field-dependent dynamic storage and loss moduli of the MREs. An experimental test is also designed to identify few constant material parameters in the model and also to validate the developed model. Results for storage and loss moduli are finally compared with those of experiment in a wide range of excitation frequency and magnetic field up to saturation. It has been shown that there is a good agreement between experiment and theoretical results.