Microstructure and electrical properties of (Ba0.6Sr0.4)0.85Bi0.1TiO3 ceramics prepared by single-step, liquid-phase, solid-state reactive sintering

(Ba0.6Sr0.4)(0.85)Bi0.1TiO3 ceramics have been obtained by single-step, liquid-phase, solid-state reactive sintering in the temperature range 1250-1350 A degrees C using stoichiometric amounts of BaTiO3, SrTiO3 and Bi4Ti3O12. Their microstructure and electrical properties have been studied by X-Ray diffraction and fluorescence, scanning and transmission electron microscopy and impedance spectroscopy. The relative density, D-r, relative permittivity, , and dissipation factor, tan delta, at room temperature and the bulk and grain boundary resistivity, R-b and R-gb, and activation energies, and , are approximately independent of the sintering temperature with values around e.g. D-r similar to 97.5 %, similar to 1790, tan delta similar to 0.06 %, similar to 26 k Omega cm, similar to 1.03 eV, similar to 217 k Omega cm and similar to 1.41 eV. By contrast, the temperature coefficient of capacitance, TCC, increases linearly from similar to 10 ppm C-o(-1) to similar to 21 ppm C-o(-1) on increasing sintering temperature. Comments on the influence of the sintering temperature on the chemical composition of the ceramics are made.