Effects of KCl/LiF Additives on the Structure, Phase Transitions and Dielectric Properties of BSPT Ceramics.

The influence of the low-melting KCl/LiF additive with molar ratio 80:20 on the structure, dielectric and ferroelectric properties of solid solutions with compositions close to morphotropic phase boundary in the (1−x)BiScO3- xPbTiO3system withx=0.635 (BSPT1) andx=0.645 (BSPT2) doped by 5, 10 and 15 w. % of KCl/LiF has been studied. Dense single phase ceramic samples have been prepared at 1313 – 1323 K (2 h) using as initial the BSPT1 and BSPT2 powders prepared from nitrate solutions. Addition of KCl/LiF led to displacement of BSPT1 and BSPT2 compositions from the initial mixture of rhombohedral and tetragonal phases to the region of the tetragonal one. This effect was accompanied by a small increase in the Curie temperatureTCvalue from 668 to 705 К in case of BSPT1 and from 672 to 714 К in case of BSPT2. Effects of additives on unit cell parameters of perovskite solid solutions, decrease in sintering temperatures, and improvement of the ceramic samples density were also found. [ABSTRACT FROM AUTHOR]