Formation of the La0.03Sr0.255Ba0.7Nb2-yTiyO6-y/2 ferroelectric ceramic system

Abstract

The study of the formation of the Sr0.255La0.03Ba0.7Nb2 - yTiyO6 - y/2 ferroelectric ceramic system and the influence of the sintering conditions and titanium concentration on the densification process is reported. A single-phase compound is observed for low titanium content (y less than or equal to 0.1) in the XRD spectra, being isostructural with the tetragonal tungsten bronze SBN phase. For high titanium concentrations (y > 0.1) the XRD patterns show, besides the tetragonal phase reflections, several small peaks evidencing an additional phase in the compound. This second phase was identified as isostructural to hexagonal Ba6Nb9Ti7O42. The grain size shows a linear increase with titanium content in the region of monophasic compositions and a possible liquid phase aided sintering process is analyzed. (C) 2000 Kluwer Academic Publishers.