EFFECT OF ELECTRIC-FIELD ON FRACTURE OF PIEZOELECTRIC CERAMICS

Closed form solutions for all three modes of fracture for an infinite piezoelectric medium containing a center crack subjected to a combined mechanical and electrical loading were obtained. The explicit mechani cal and electrical fields near the crack tip were derived, from which the strain energy release rate and the total potential energy release rate were obtained by using the crack closure integral. The suitabilit y in using the stress intensity factor, the total energy release rate, or the mechanical strain energy release rate as the fracture criterio n was discussed.