Domain switching anisotropy in poled lead titanate zirconate ceramics under orthogonal electromechanical loading

Domain switching process in aged lead titanate zirconate ceramics after hyper- TC (TC is the Curie temperature) poling was studied under two types of orthogonal electromechanical loading: (i) axial electric field E3 coupled with lateral compression stresses 11 and (ii) axial compression stresses 33 coupled with lateral electric fields E1. It is found that in the lateral direction, both the coercive field and the switchable polarization are significantly smaller than that in the original poling direction and that the lateral coercive field does not decrease but increase with the increasing axial compression, which contradicts with the widely accepted domain switching criterion by Hwang [Acta. Metall. Mater. 43, 2073 (1995)]. The alignment of defect dipoles during aging, together with its effect on domain switching, is employed to explain the observed domain switching anisotropy. Furthermore, the domain stabilizing effect of aligned defect dipoles may lead to a design of large electrostriction actuators.