Intrinsic/extrinsic interplay contributions to the functional properties of ferroelectric-magnetic composites

Recent literature data about the preparation and the functional properties of two phase ceramic composites comprising of a ferroelectric perovskite and a magnetic ferrite are presented and critically compared, together with new results found in BaTiO3-(Ni,Zn)Fe2O4 composites. The phase assemblage and the spontaneous strain of the ferroelectric perovskite, the microstructural aspects and the phase percolation problem, the functional properties (resistivity, magnetic, dielectric, ferroelectric and magnetoelectric coupling) and the use of effective field models for predicting the permittivity and permeability of these composites are discussed in detail.