Theoretical model for the magnetoelectric effect in magnetostrictive/piezoelectric composites

A theoretical model for the longitudinal magnetoelectric effect in laminate composites comprising magnetostrictive and piezoelectric phases is presented. The model characterizes the magnetoelectric media in terms of its permeability, permittivity, and magnetoelectric-susceptibility tensor. A distinct approach to model the media is presented, in which fundamental electromagnetic boundary conditions are applied to all fields existing at the interface between the layers, and in the composite material in general. The application of the boundary condition used here represents a change from previous models where quasistatic approximations are used, including open circuit conditions imposed on the electric displacement field. The model presented here takes into account the imperfect coupling in terms of the existing mechanical forces (stress, strain) that can occur at the interface of such layered composites. An interface coupling parameter is used to model the strain relationship between layers of the composite. Results of the theoretical model are compared to experimental data and show much better results than previously obtained.