Heat Capacity and Dielectric Properties of the PNN-PT Ferroelectric Ceramics

Abstract

A study of dielectric permittivity and heat capacity of the (1-х)PbNi_1/3Nb_2/3O₃ – хPbTiO₃ solid solution system (x = 0.3, 0.4, 0.5) within the 290–700 K range is reported. Temperatures of phase transitions T_m determined from maximums of dielectric permittivity ϵ depends on the content of PbTiO₃. A broad phase transition is shown to proceed in the 0.7PbNi_1/3Nb_2/3O₃–0.3PbTiO₃ composition around 312 K. Specific to phase transitions anomalous heat capacity is observed at Т ≈ 520 K in all compositions studied.

Keywords:

• Ferroelectric ceramics
• dielectric permittivity
• heat capacity
• phase transition