Palaimiene Edita, Macutkevic Jan, Banys Juras, Winiarski Antoni, Gruszka Irena, Koperski Janusz, Molak Andrzej
Institute of Applied Electrodynamics and Telecommunications, Vilnius University, Sauletekio av. 3, LT-10257 Vilnius, Lithuania.
Institute of Physics, University of Silesia, ul. 75 Pułku Piechoty 1, PL-40-500 Chorzów, Poland.
Materials (Basel). 2020 Jun 25;13(12):2854. doi: 10.3390/ma13122854.
The dielectric properties of BaCaTiO ( = 0.17) ceramics were studied in a wide frequency range of 20 Hz-53 GHz. Diffused ferroelectric phase transition was revealed close to 339 K in the dielectric properties of ceramics. The behaviour of distributions of relaxation times in vicinity of the ferroelectric phase transition temperature is also typical for order-disorder ferroelectric phase transition. However, at lower temperatures (below 200 K), the most probable relaxation increased according to the Arrhenius law. At lower temperatures the maximum of the imaginary part of dielectric permittivity versus temperature strongly shifted to higher temperatures when the frequency increased (from 125 K at 1.21 kHz to 300 K at 33 GHz). This behaviour was attributed to the dynamics of Ti ions. The origin of the crossover from ferroelectric to relaxor behaviour of BaCaTiO ( = 0.17) ceramics is discussed in the paper.
研究了BaCaTiO(= 0.17)陶瓷在20 Hz - 53 GHz宽频率范围内的介电性能。在陶瓷的介电性能中,发现接近339 K时存在扩散铁电相变。铁电相变温度附近弛豫时间分布的行为对于有序 - 无序铁电相变也是典型的。然而,在较低温度(低于200 K)下,最可能的弛豫根据阿仑尼乌斯定律增加。在较低温度下,当频率增加时(从1.21 kHz时的125 K到33 GHz时的300 K),介电常数虚部最大值随温度强烈向高温移动。这种行为归因于Ti离子的动力学。本文讨论了BaCaTiO(= 0.17)陶瓷从铁电行为到弛豫铁电行为转变的起源。