Orientation-dependent,field-induced phase transitions in soft lead zirconate titanate piezoceramics

In situ high-energy X-ray diffraction (XRD) was performed on lead-zirconate-titanate-based ferroelectric materials with composition near the morphotropic phase boundary (MPB). The utilization of the two-dimensional area detector in in situ field-dependent experiments enables the complete analysis of the material response with respect to all azimuthal angles at each field amplitude. The studies reveal that the field-induced phase transition from tetragonal to rhombohedral is dependent on crystal orientation in Nb-doped PbZr_0.53Ti_0.47O₃ that is in close compositional proximity to the MPB. However, only domain wall motion is activated in Nb-doped PbZr_0.50Ti_0.50O₃, which is further in composition from the MPB. This synchrotron-based XRD characterization approach illustrates the importance in evaluating the orientation-dependence of phase transitions in piezoelectric and ferroelectric polycrystalline materials.