Micromagnetic model for the influence of biaxial stress on hysteretic magnetic properties

Abstract

A micromagnetic formulation has been developed for modeling the effect of biaxial stress on magnetoelastic processes in polycrystalline steels. In particular, the formulation employs the Schneider–Cannell–Watts model and involves substitution of an effective stress equal to one of the deviatoric (i.e., distortional) normal stress components, depending on whether the field is parallel to a tensile or compressive axis or to the third axis perpendicular to the plane of biaxial stress. Computer results are compared to experimental results on the effects of biaxial stress on magnetic properties in mild steel and in SAE-4130 steel. Good qualitative agreement is found in almost all cases, in that in going from one biaxial stress case to the next, the same kinds of changes are seen magnetically. It is also shown from the model and the data that a method can be formulated to nondestructively determine the difference in biaxial stresses.