Influence of sintering method on microstructure, electrical and magnetic properties of BiFeO3–BaTiO3 solid solution ceramics

The (1- x )BiFeO 3 - x BaTiO 3 (short for (1- x )BFO- x BTO, x  = 0.2–0.4) ceramics were prepared by solid-state reaction with microwave sintering (MWS) and conventional sintering (CS) methods. The crystal structure, microstructures, dielectric properties , ferroelectric properties , and magnetic properties of BFO-BTO ceramics sintered by MWS and CS were systematically investigated. It is found that the MWS can effectively decrease the grain size and enhance the compactness of BFO-BTO ceramics. The X-ray diffraction (XRD) results confirm that all ceramics exhibit a single perovskite structure, and the phase transforms from rhombohedral in BiFeO 3 -rich compositions to pseudo-cubic phase gradually as x increases. Introducing BTO into BFO can strengthen its dielectric relaxation behavior. Compared with CS, the MWS samples have a lower remanent polarization ( P r ) and a smaller coercive field ( E c ) under the same electric field. Therefore, MWS contributes to the decrease of dielectric loss. Addition of BTO can contribute to the reduction of the coercive force ( H c ) of BFO-based ceramic, and so decrease the hysteresis loss. At the same time, its remanent magnetization ( M r ) value can be decreased by introducing BTO into BFO and using MWS method. The present research provides a route for decreasing the dielectric loss and hysteresis loss of BiFeO 3 -based ceramics using the MWS method.