Theoretical approach to the coupled thermal-electrical-mechanical properties of inhomogeneous media

A generally theoretical framework for predicting the coupled thermal-electrical-mechanical properties of inhomogeneous media is developed in terms of a Green’s-function method and perturbation theory. Taking a tranversely isotropic fiber-reinforced composite of the 4- or 6-mm symmetry class as a practical example, I discuss the general theoretical results, and give explicit expressions for the effective coupled thermal-electrical-mechanical properties. The pyroelectricity of ${\mathrm{BaTiO}}_3$-epoxy and CdS-epoxy composites is numerically analyzed. An enhanced pyroelectricity is predicted, and the numerical results show the interesting behavior of these materials.