Effect of remanent polarization on electro-mechanical fields near an elliptic cavity or a crack in piezoelectric ceramics

In this paper the effect of remanent polarization on electric-mechanical fields near an elliptic cavity or a crack in piezoelectric ceramics is studied. The analysis is based on the application of exact electric boundary conditions at the rim of an elliptic cavity and/or a crack. The solutions are derived in a closed form in terms of complex potentials. The result shows that the cavity problem of remanent polarization is similar to the problem of general strain mismatch and the effect of remanent polarization can not be omitted. The same conclusion can also be obtained by adopting the nonlinear boundary conditions for a sharp crack problem. By use of this model we can get calculation results to explain some experimental results.