Effect of internal stresses on temperature-dependent dielectric properties of Fe-doped BZT ceramics

Fe-doped BaZr0.1Ti0.9O3 (BZT) ceramics were prepared by the conventional solid state reaction route, and the effect of internal stresses on their crystal structure, diffuse phase transition and temperature-dependent dielectric properties were studied. X-ray results showed a single perovskite structure, and the diffraction peaks to shift with the change of internal stresses that were both compressive stress and tensile stress as determined by the XRD sin(2)psi technique. The relation between internal stresses and the tetragonality indicated that these could originate from lattice distortions. A completely different effect of the types of internal stresses on the dielectric properties was observed. The tensile stresses could stabilize the tetragonal structure, increase the dielectric constant and reduce the dielectric loss. Tensile stresses would decrease the long range polar ordered region and enhance the degree of the diffuse phase transition, which stabilized the temperature-dependent dielectric properties. Importantly, the increasing tensile stresses or decreasing compressive stresess were effective to stabilize the temperature-dependent dielectric properties.