Energy release rate and bifurcation angles of piezoelectric materials withantiplane moving crack

The dynamic fracture problems of the piezoelectric materials with antiplane moving crack are analysed by using function of complex variable in the pap er. The results show that the coupled elastic and electric fields inside pi ezoelectric media depend on the speed of the crack propagation, and have si ngularity at the crack tip. The stress intensity factor is independent of t he speed of the crack propagation, which is identical to the conclusion of purely elasticity. Moreover, independent of the electric loading, the dynam ic energy release rate can be expressed by the stress intensity factor and enlarge with the increase of crack speed. High speed of the crack moving co uld impede the crack growth. At the same time, the crack can be propagated into either curve or bifurcation if the crack speed is higher than the crit ical speed.