New developments concerning piezoelectric materials with defects

The problem of a piezoelectric body with an elliptic cavity is revisited within the framework of two-dimensional electro-elasticity. In contrast to our previous formulation, the present analysis is based on the use of exact electric boundary conditions at the rim of the hole, thus avoiding the common assumption of electric impermeability. Expressions for the elastic and electric variables induced inside and outside the cavity are derived in closed form in terms of complex potentials. Comparisons between present (exact) and previous (approximate) models are effected to establish the limitations associated with the assumption of the impermeable hole, in particular when it becomes a slit crack. Copyright (C) 1996 Elsevier Science Ltd.