Effect of polarization saturation on the stress intensity factor for a crack in an electrostrictive ceramic

A crack with electrically impermeable surfaces in an electrostrictive ceramic with perfect saturation under electric loading is analysed. A strip saturation model is introduced to investigate the effect of the electrical polarization saturation on the stress intensity factor. The solutions of electric and elastic fields for the insulating crack with a strip saturation zone under large-scale saturation conditions are derived using the complex function theory. The stress intensity factor is obtained on the basis of the strip saturation model and is compared with that obtained on the basis of the small-scale saturation model. It is found that the two models predict nearly indistinguishable stress intensity factors.