Effects of electric field and poling on the fatigue of cracked piezoelectric ceramics in cyclic three-point bending

This paper deals with the fatigue behavior of cracked piezoelectric ceramics in cyclic bending under electric fields both numerically and experimentally. Fatigue tests were carried out in three-point bending with the single-edge precracked-beam specimens. The crack was created normal to the poling direction. Number of cycles to failure was measured under different electric fields. A plane strain finite element analysis was also performed, and the effect of polarization switching on the energy release rate was discussed under a high negative electric field. In addition, possible mechanisms for crack growth were discussed by scanning electron microscope examination of the fracture surface of the piezoelectric ceramics.