Grain Growth Behavior of 0.95(Na0.5Bi0.5)TiO3-0.05BaTiO3 Controlled by Grain Shape and Second Phase.

The grain growth behavior of 0.95(Na0.5Bi0.5)TiO3-0.05BaTiO3 (mole fraction, NBT-5BTdid not appear in any of the NBT-5BT samples with excess Bi2O3. The amount of liquid phase increased as the amount of Bi2O3 increased. Therefore, the rate of grain growth could be decreased by the increasing the distance for the diffusion of atoms. These observations allowed us to conclude that the growth of Bi2O3-excess NBT-5BT grains is governed by the growth of facet planes via the two-dimensional nucleation grain growth mechanism during changing grain shape and amount of liquid.