Study of relaxor behavior in a lead-free (Na 0.5 Bi 0.5 )TiO 3 -SrTiO 3 -BaTiO 3 ternary solid solution system

Abstract In this work, single phase lead-free (0.8- x )(Na 0.5 Bi 0.5 )TiO 3 −0.2SrTiO 3 - x BaTiO 3 (NBT-ST-BT) ceramics were prepared by conventional solid state reaction method. The effect of BT on the structure and on the dielectric and ferroelectric properties of NBT-ST-BT were investigated. A structural transformation from pseudo-cubic to tetragonal along with possible phase coexistence was witnessed as the BT content was increased. A diffuse phase transition with considerable frequency dispersion in the dielectric response and slim P-E loops evidenced strong relaxor behavior for the ternary system at higher compositions of BT. An analysis of the frequency dependent T m according to V-F and Power law indicated substantial interaction between the polar nano-regions and relatively broad distribution of freezing temperatures. The study of the dielectric constant at much higher and lower temperatures than T m in the range of Burn's temperature (T B ) to freezing temperature (T f ) to provide useful information about the growth rate of polar nano-regions and their interactions for a better understanding of the relaxor behavior exhibited by the present ternary system.