Processing and electrical properties of BiFeO3-PbTiO3 ceramics

Polycrystalline (1-x)BiFeO3-(X)PbTiO3 ceramics (where x=0.3) have been produced via a mixed oxide route with densities in excess of 95% of the theoretical. X-ray diffraction studies indicate that the fully sintered materials are phase pure and close to the morphotropic phase boundary (MPB) between the rhombohedrally distorted and tetragonally distorted perovskite structures. Materials sintered between 10 15 and 1025 degreesC display high resistivities, even at elevated temperatures, allowing the relative permittivity to be measured up to and through the Curie point, presently found to be 650 degreesC. Measurements of polarization-field hysteresis loops indicate that the coercive field for this material approaches 15 kV mm(-1). (C) 2004 Elsevier B.V. All rights reserved.