Fatigue in bulk lead zirconate titanate actuator materials:: A review

Fatigue in ferroelectric ceramics is the gradual change of material properties with cyclic loading. It is caused by microscopic material modifications of mechanical or electrical origin. Due to the electromechanical coupling, both mechanisms can yield similar or even identical changes in properties. Macroscopically, a reduction of switchable polarization is anticipated and asymmetries in the macroscopic hysteresis curves arise due to charge carrier migration. This review elaborates on the multiple loading scenarios that lead to asymmetries in material response and loss in performance. The disparities between unipolar, bipolar, and mixed electromechanical loading are displayed. Possible microscopic origins are categorized. The strong similarities in the roles of microcracks, dielectric layers, and grain boundaries are worked out.