Dielectric, ferroelectric, magnetic, and magnetoelectric properties of multiferroic laminated composites

Multiferroic laminated composites consisting of lead-zirconate titanate (PZT)/polyvinylidene-fluoride (PVDF) particulate composite layers and Tb-Dy-Fe alloy (Terfenol-D)/PVDF particulate composite layers, prepared by a simple hot-molding technique, were reported. In the laminated composites, the polymer PVDF is inert and used just as a binder. The measured dielectric, ferroelectric, magnetic, and magnetoelectric properties demonstrate strong dependence on volume fraction f of the PVDF in the laminated composites. As f is low (e.g., $f<0.3),$ a low concentration of binder leads to low quality of the composites and thus low performance. Better performance of the composites appears in the intermediate f range. As f further increases, high concentration of the inert PVDF results in weak dielectric, magnetostrictive, piezo- and magnetoelectric responses of the laminated composites. Our results illustrate that the three-phase laminated composites exhibit remarkable magnetoelectric effect especially at high frequency at which the electromechanical resonance appears.