Micromechanics approach to the magnetoelectric properties of laminate and fibrous piezoelectric/magnetostrictive composites

We use a micro mechanics approach to study the magnetoelectric (ME) properties of the piezoelectric/magnetostrictive composite with a 2-2 laminate structure and a 3-1 fibrous structure. It is found that the 3-1 composite has a higher ME coefficient than the 2-2 one, if the volume ratio of piezoelectric material is the same. The reason is that the 3-1 fibrous composite makes use of the longitudinal piezoelectric response and the piezoelectric voltage constant g(33) is 2-3 times that of g(31). Generally, a smaller volume ratio of the piezoelectric material will generate a higher ME response. The tensile stress at the piezoelectric/magnetostrictive interface of the 3-1 fibrous composite. however. could be high enough to induce plastic deformation or microcracks, which leads to a ME coefficient lower than the theoretically predicted one.