Multiscale finite element modelling of pattern formation in magnetostrictive composite thin film

Abstract

A multiscale finite element model with subgrid-scale spatial homogenization and stability estimate for time discretization in the context of magnetostrictive composite thin-film micromagnetics are reported in this paper. Developments of the phenomenological microscopic constitutive model and the subsequent multiscale approach are aimed at analyzing the formation of magnetic domains in Terfenol-D/epoxy thin film under transverse magnetic (TM) mode of excitation. The phenomenological constitutive model is based on the density of domain switching (DDS) of an ellipsoidal inclusion in a unit cell. The subgrid-scale spatial homogenization works as a method of upwinding the small-scale micromagnetism and magnetostriction to the larger length scale. Numerical results indicate complex features of this thin-film dynamics, such as the formation of connected domains.