Grain Size Dependence of Third Nonlinear Piezoelectric Coefficient in Lead Zirconate Titanate Ceramics

Piezoelectric Lead Zirconate Titanate (PZT) ceramics with different grain sizes were fabricated by changing the firing conditions. Using these samples, the grain size dependence of the third nonlinear piezoelectric coefficient in the transverse direction, ξ D31, was experimentally investigated. The ξ D31 decreased with the increase of grain size. This decrease of ξ D31 was assumed to be caused by the promotion of poling in the samples with large grains. In order to demonstrate this fact, poling field dependence and MnO additive dependence of ξ D31 were investigated. From the results of these three items of dependence, we concluded that the nonlinear motion of residual domain walls in poled samples exerts a large influence on the ξ D31 value.