Phase Transitions In Doped And Undoped Lead Zirconate Titanate Piezoelectric Materials

The study of the anelastic behaviour versus temperature at medium and low frequencies for undoped and doped lead zirconatetitanate –PZT- reveals the presence of two peaks P1 and P2. According to the phase diagrams established for PZT materials, P1 peak could be related to the Curie transition between tetragonal ferroelectric phase and the cubic paraelectric phase, whereas the P2 peak could be related to the morphotropic phase transition between rhombohedral and tetragonal ferroelectric phases. Both P1and P2 peaks evolutions are in accordance with several existing literature models for explaining the first order phase transition. The introduction of potassium and niobium dopants changes the nature of the phase transition process.