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Anisotropic solid-state magnetorheological (MR) composites are prepared by applying magnetic fields to isotropic suspensions in polymer melts and preserved by cross-linking the melts. The composities are studied through a continuum-level perspective at various magnetic field strengths under oscillatory shear. The minimum number of constraints are applied in the derivation of the magnetic and rheological invariants, which relate the measured macroscopic magnetostriction coefficients to the discrete parameters of any microscopic model. The field-induced stress is defined by magnetostriction coefficients, which are material parameters that describe the strain dependence of the magnetization tensor. A comparison of the independently measured rheological and magnetic properties allow for the determination of the magnetostriction coefficients.

A method for simulating the steady-shear behavior of bidisperse, nonlinearly magnetizable MR suspensions is described. Results show that the yield stress of suspensions containing mixtures of large and small particles is larger than that of monodisperse suspensions, in agreement with previous experimental results.