Magnetic Field-Induced Compressive Property of Magnetorheological Elastomer under High Strain Rate

The dynamic compressive property of magnetorheological elastomer (MRE) under high strain rate was investigated using a modified split Hopkinson pressure bar system. Both the compressive properties in the pre-yield region and the post-yield region were studied. Experimental results show that the dynamic compressive property of MRE under high strain rate is related to the magnetic field and the strain rate. In the pre-yield region, with increasing magnetic field or strain rate, both the Young’s modulus and the yield stress increase. However, the yield strain decreases with increasing magnetic field or strain rate. A constitutive model consisting of hyperelasticity, viscoelasticity, and a magnetic part was proposed to describe the compressive property of MRE, and the model agrees well with the experimental results. In the post-yield region, the stress first decreases to a minimum value and then increases smoothly when the strain exceeds the yield strain, which is due to the change of the chainlike structures of iron particles in MRE.