Fatigue tests on lead zirconate titanate (PZT) were performed by using single-edge-V-notched specimens under cyclic mechanical loading with or without superposition of a DC electric field. Fatigue life was prolonged by applying a DC electric field to the PZT ceramics. To estimate the domain contribution, fatigue tests on barium strontium titanate (BST) ceramics in both ferroelectric and paraelectric phase were carried out. The fatigue life of the ferroelectric phase was much shorter than that of the paraelectric phase. Comparing the fatigue lives of two PZT ceramics with different values of coercive electric field (Ec) revealed that the fatigue life of the PZT with higher Ec is about one order of magnitude longer than that with lower Ec when the stress-intensity factor of fatigue test is low. It is therefore concluded that non-180°domain switching probably deteriorates the fatigue life of ferroelectric ceramics.
Relaxation or breakup of a low-conductivity drop upon removal of a uniform dc electric field
