On the importance of interchain interaction and rotational contribution to the computation of the yield stress in magnetorheology

Traditionally, finite element method magnetostatics simulations used in magnetorheology consider that the shearing affine deformation of the particle lattice can be divided in two motions: first, an elongation, and second, a rotation of the elongated structure. This allows reducing the magnetostatic problem to an axisymmetric one with a smaller computational cost. However, supposed symmetries also impose, without any physical reason, that both the magnetic field direction and particle magnetization are aligned with the chain axis for any strain. The first assumption leads to an incorrect interchain interaction while the second one neglects the magnetization rotation during the strain process. In this letter we analyze the limitations within these classical assumptions under the frame of a recently proposed reduced field formulation that is capable to truly simulate large shear strains and concentrations in model structures (Compos. Part B: Eng. 160 626-31).