Pressure-temperature phase diagrams for several modified lead zirconate ceramics

Using dielectric constant and loss measurements we have determined the pressure-temperature phase diagrams of four ferroelectric ceramics based on lead zirconate (PbZrO₃). The materials chosen for study all have pressure-induced ferroelectric to antiferroelectric transitions at ∼0.3 GPa. In all four materials, five phases were identified by comparing our results with studies, previously published by other workers, of the phase behavior of modified PbZrO₃ materials as a function of composition and temperature. The observed phases are the ideal cubic perovskite paraelectric phase, two rhombohedral ferroelectric phases, and two antiferroelectric phases, one orthorhombic and one pseudotetragonal. Comparison is made with previous temperature-composition studies of modified PbZrO₃ materials.