Journal of Advanced Dielectrics (Oct 2019)
Dielectric behaviors and relaxor characteristics in Bi0.5Na0.5TiO3-BaTiO3 ceramics
Abstract
Microstructure and dielectric behaviors of heating/cooling and bias-field were investigated in lead-free ceramics (1−x)Bi0.5Na0.5TiO3−xBaTiO3 (BNT−xBT, x=0, 0.02, 0.04, 0.06, 0.08 and 0.10). The relaxor characters and the Vogel–Fulcher law of frequency-dependent dielectric properties were analyzed. Three dielectric anomalies with pronounced frequency dispersion at Td, a maximum dielectric with variable frequency-dispersion at Tm and a third Maxwell–Wagner-type relaxation over a wide temperature range in high-temperature region were observed. The significant dielectric thermal hysteresis, low barrier energy, high freezing temperature in heating process and the maximum dielectric tunability appeared in x=0.4 ceramic.
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