On singularities in composite piezoelectric wedges and junctions

The plane problems of piezoelectric wedges and multi-material wedges/juncti ons involving piezoelectrics are studied in this payer. The study is focuse d on the singular behaviour of electroelastic fields at the corner of wedge s and junctions, The polarization orientation of the piezoelectric medium m ay be arbitrary. The problem is formulated by extending Lekhnitskii's compl ex potential functions. In the homogeneous piezoelectric cases of a half pl ane and a semi-infinite crack, it is shown that the singularity is invarian t with respect to the direction of polarization and explicit solutions are derived for homogeneous boundary condition combinations. In general cases i nvolving multi-material systems, the or der of singularity is determined by solving a transcendental characteristic equation derived on the basis of b oundary conditions and geometry. The accuracy of the numerical algorithm is verified by comparing with the existing results for pure elastic wedges. N umerical results of homogeneous piezoelectric wedges indicate that electric boundary conditions have a significant effect on the order of singularitie s. a selected set of practically useful wedges and junctions involving piez oelectrics are studied to examine the influence of wedge angle, polarizatio n orientation, material types, and boundary and interface conditions on the order of singularity of electroelastic fields. (C) 2000 Elsevier Science L td. All rights reserved.