Collinear permeable cracks between dissimilar piezoelectric materials

In this paper, the generalized two-dimensional problem of collinear interfa cial cracks, between two dissimilar piezoelectric media subjected to piecew ise uniform loads at infinity, is studied by means of the Stroh formalism. It is different from the relevant analysis done by other authors that in th e present work, cracks are considered to be traction-free, but permeable sl its across which both the normal component of the electric displacement and the tangential component of the electric field are continuous, and thus av oiding the common assumption of electric impermeability. According to the a bove continuous conditions combined with the principle of analytical contin uation, the considered problem is reduced to a Hilbert problem. Explicit, c losed-form expressions for the electric held inside cracks, complex potenti als in piezoelectric media and field intensity factors near the crack tips are obtained. These results show that the electric held inside cracks is de pendent on the material constants and the applied loads. It is also shown t hat all the field singularities are dependent only on the applied mechanica l loads, not on the applied electric loads, which is different from those r esults based on impermeable crack model. (C) 2000 Elsevier Science Ltd. All rights reserved.