Effective electromechanical properties of transversely isotropic piezoelectric ceramics with microvoids

In most piezoelectric materials and smart structures, the presence of microvoids can hardly be avoided. In the present paper, detailed three-dimensional (3-D) finite element analyses based on the unit cell method are carried out to investigate the inherent relations between the effective properties and the non-uniform distributions of microscopic electromechanical coupling fields resulting from microvoids. The emphases are placed on the influences of void volume fraction, void distribution, void shape and configuration on the effective properties of voided piezoelectric ceramics. The influences rooting in the permeability of voids and piezoelectricity of matrix materials on the effective properties of voided piezoelectric ceramics are also studied. The results obtained by this study have prospective guiding significances to the structural integrity analyses and fabrication of piezoelectric ceramics.