Understanding the role of grain size on the structural and dielectric properties of BZT-BCT systems

Reference Presenter Authors
(Institution)
Abstract
08-049 Cristina Elena Ciomaga Ciomaga, C.(Al. I. Cuza University of Iasi); Curecheriu, L.(Al. I. Cuza University of Iasi); Padurariu, L.(Al. I. Cuza University of Iasi); Buscaglia, M.(Institute of Condensed Matter Chemistry and Technologies for Energy, National Research Council); Buscaglia, V.(Institute of Condensed Matter Chemistry and Technologies for Energy, National Research Council); MITOSERIU, L.(Al. I. Cuza University of Iasi);
0.5Ba(Zr0.20Ti0.80)O3-0.5(Ba0.70Ca0.30)TiO3 (BZT-BCT) ceramics have been studied in order to understand the role of grain size (GS) on the intrinsic/extrinsic contributions to structural and dielectric properties at its triple point for searching an optimal size. The powders were prepared by the conventional solid-state route and calcined at 1000°C/4 hours. Dense ceramics (relative density above 94-98%) with different grain size were obtained by sintering the resulted powders at temperatures between 1400-1500°C for different times (from 0.2-24 hours). The grain size of ceramics were between 2?m, for the samples sintered at 1400ºC/2h, to 27?m, for the samples obtained at 1500ºC/24h. The structural characterization was performed for monitoring the effect of grain size and field on the phase composition in BCTZ ceramics. The evolution of polar order and phase transitions with grain size has been studied using dielectric permittivity measurements at 20Hz- 2MHz between 25 and 150°C. In addition, we develop a mesoscale modelling (Monte Carlo with Finite Element Method calculations) to describe size effects on the low-field properties in BCTZ ceramics. The presented data provide a complete picture of the size effect dependence of functional properties in BZT-BCT ceramics.
 Acknowledgment: The financial support of the PN III-P1-1.1-TE-2016-1951 is acknowledged.
<< Back
Copyright © 2019 Metallum. All rights reserved.
Site produced by: SITESP.NET