Effect of oxygen assisted sintering on piezoelectric properties of SrBi4Ti4O15 ceramics prepared via high energy mechanochemical processing

Polycrystalline layered structure SrBi4Ti4O15 (SBT) ferroelectric ceramics were synthesized via the solid-state reaction method. The high energy mechanochemical processing resulted in nanometer sized particles of SBT phase. The complete phase formation of layered structure SBT was observed after calcination at 800 degrees C. Highly dense SBT ceramics were obtained after sintering at 1200 degrees C in an oxygen atmosphere. The presence of oxygen during sintering reduced the porosity and dense microstructures were obtained. The density was found to be > 96% of theoretical density. The phase formations in steps from milled to sintered were observed from XRD pattern and the SEM micrograph exhibited platelet-like morphology of SBT. TEM was done to estimate the particle size of the powders. Electrical properties of SBT ceramics viz, dielectric, piezoelectric charge coefficient and ferroelectric hysteresis measurements were made. Resonance measurements were made in order to determine the electromechanical coefficient and elastic compliances. The results of all of the aforementioned are presented in this paper. (C) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.