Electrical properties of Na0.5Bi0.5TiO3-SrTiO3 ceramics

At the present time, the most widely-used piezoelectric material belongs mainly to the PZT solid solution system (1 - x) PbTixO3 - x ZrTiO3. Because of the possible evaporation of lead oxides during the sintering of such ceramics, lead free or low lead content piezoelectric materials are actually extensively investigated in order to replace PZT based ceramics. Sodium bismuth titanate, Na0.5Bi0.5TiO3 (NBT) could be a good candidate for such applications because this compound is ferroelectric at room temperature up to about 525 K. As for PZT ceramics, the formation of solid solutions could be a way to improve the electrical properties of such materials. In opposition to previous studies using ferroelectric compounds such as PbTiO3 or BaTiO3\, it could be interesting to study the influence of a non ferroelectic compound such as SrTiO3 (ST) in the formation of solid solutions and in their electrical properties. At the present time, only partial studies of this system were published [1, 2]. Therefore the (1 - x) Na0.5Bi0.5TiO3 - x SrTiO3 system was systematically investigated.