This paper investigates the dielectric properties of （Na0.5K0.5Bi）0.5TiO3 crystal at intermediate frequencies （1kHz〈 f 〈IMHz） in the temperature range of 30-560℃. A pronounced high-temperature diffuse dielectri...This paper investigates the dielectric properties of （Na0.5K0.5Bi）0.5TiO3 crystal at intermediate frequencies （1kHz〈 f 〈IMHz） in the temperature range of 30-560℃. A pronounced high-temperature diffuse dielectric anomaly has been observed. This dielectric anomaly is shown to arise from a Debye-like dielectric dispersion that slows down following an Arrhenius law. The activation energy Er obtained in the fitting process is about 0.69eV. It proposes that the dielectric peak measured at low frequency above 400℃ is not related to the phase transition but to a space-charge relaxation.展开更多
Based on Clausius-Mosotti equation and Debye relaxation theory, the dielectric model of yttria ceramics was developed according to the dielectric loss mechanism. The dielectric properties of yttria ceramics were predi...Based on Clausius-Mosotti equation and Debye relaxation theory, the dielectric model of yttria ceramics was developed according to the dielectric loss mechanism. The dielectric properties of yttria ceramics were predicted at high temperature. The temperature dependence and frequency dependence of dielectric constant and dielectric loss were discussed, respectively. As the result, the data calculated by theoretical dielectric model are in agreement with experimental data.展开更多
基金Project supported by the National Nature Science Foundation of China （Grant No 50572056）.
文摘This paper investigates the dielectric properties of （Na0.5K0.5Bi）0.5TiO3 crystal at intermediate frequencies （1kHz〈 f 〈IMHz） in the temperature range of 30-560℃. A pronounced high-temperature diffuse dielectric anomaly has been observed. This dielectric anomaly is shown to arise from a Debye-like dielectric dispersion that slows down following an Arrhenius law. The activation energy Er obtained in the fitting process is about 0.69eV. It proposes that the dielectric peak measured at low frequency above 400℃ is not related to the phase transition but to a space-charge relaxation.
文摘Based on Clausius-Mosotti equation and Debye relaxation theory, the dielectric model of yttria ceramics was developed according to the dielectric loss mechanism. The dielectric properties of yttria ceramics were predicted at high temperature. The temperature dependence and frequency dependence of dielectric constant and dielectric loss were discussed, respectively. As the result, the data calculated by theoretical dielectric model are in agreement with experimental data.
