Effect of magnetic domain structure on longitudinal and transverse magnetoelectric response of particulate magnetostrictive-piezoelectric composites

Phase field modeling and simulation reveal that the magnetoelectric response of particulate magnetostrictive-piezoelectric composites sensitively depends on the magnetic domain structures of magnetostrictive phase. It is found that the longitudinal and transverse magnetoelectric coefficients of particulate composites with isotropic two-phase microstructures can be effectively tailored by controlling the magnetic domain structures. It is shown that engineered magnetic domains via controlled internal residual stress through appropriate processing, such as co-sintering under external stress (rather than isostatic pressing) in analogy to stress annealing of magnetostrictive materials, provide a powerful means to optimize magnetoelectric responses of particulate composites without fabricating anisotropic two-phase microstructures (e.g., laminate, fiber/rod).