A unified model for piezocomposites with non-piezoelectric matrix and piezoelectric ellipsoidal inclusions

In this paper\ the closed!form solutions of the electroelastic Eshelby|s tensors of a piezoelectric ellipsoidal inclusion in an in_nite non!piezoelectric matrix are obtained via the Green|s function technique[ Based on the generalized Budiansky|s energy!equivalence framework and the closed!form solutions of the electroelastic Eshelby|s tensors\ a uni_ed model for multiphase piezocomposites with the non!piezoelectric matrix and piezoelectric inclusions is set up[ The closed!form solutions of the e}ective electroelastic moduli of pie! zocomposites are also obtained[ The uni_ed model has a rigorous but simple form\ which can describe the multiphase piezocomposites with di}erent connectivities\ such as 9 2\ 0 2\ 1 1\ 1 2\ 2 2 connectivities\ etc[ It can also describe the e}ects of non!interaction and interaction among the inclusions[ As examples\ the closed!form solutions of the e}ective electroelastic moduli are given by means of the dilute solution for the 9 2 piezocomposite with transversely isotropic piezoelectric spherical inclusions and by means of the dilute solution and the Mori Tanaka|s method for the 0 2 piezocomposite with two kinds of transversely isotropic piezoelectric cylindrical inclusions[ The predicted results are compared with experimental data\ which shows that the theoretical curves calculated by means of the Mori Tanaka|s method agree quite well with the experimental values\ but the theoretical curves obtained by the dilute solution agree well with the exper! imental values only when the volume fraction of the ceramic inclusion is less than 9[2[ The results in this paper can be used to analyze and design the multiphase piezocomposites