Analysis of poling induced cracking in thick walled cylinders

Stresses and electric fields induced in the poling processes of both polycrystalline and single crystal thick walled cylinders are investigated and compared using a finite element analysis together with a micro-mechanical ferroelectric constitutive law. The analysis reveals that the polarization process begins at the inner diameter and spreads outward through the cylinder as the applied electric potential is increased. The piezoelectric strain and the remnant strain produce strain fields that are not compatible with the geometry. In the single crystal material the poling is not uniform. It is affected by the angle between the crystal orientation and the electric field direction.