Internal friction study on low-temperature phase transitions in lead zirconate titanate ferroelectric ceramics

In this work, a bulk thermodynamics and microstructure study of lead zirconate titanate ferroelectric ${\mathrm{PbZr}}_{\text{0.52}}{\mathrm{Ti}}_{\text{0.48}}{\mathrm{O}}_3$ is performed through internal friction, Young’s modulus, differential scanning calorimetry (DSC), and electron diffraction measurements. Two internal friction peaks are observed near 261 and 225 K. The former correlates with an enthalpy change revealed by DSC data and is ascribable to a first-order tetragonal-to-monoclinic phase transition. The latter (225 K), however, showing asymmetric line shape together with a dramatic decrease in Young’s modulus, might correspond to a phase transition associated with the motion of domain walls. The emergence of new domains is evidenced from the superlattice reflections, and the direction of the superlattice is along the z-axis, as indicated by electron diffraction.