This paper presents mechanics based tools for the design of multifunctional polymer composite materials. The class of composite discussed consist of a low permittivity matrix material (typically polymer) with ferroelectric inclusions (piezoelectric/ferroelectric particles, rods, platelets) dispersed throughout. The high permittivity of the inclusions causes the electric field to concentrate in the matrix, which makes it challenging to get the electric field into the inclusions. Elasticity (biharmonic Laplace’s equation) and electrostatics (harmonic Laplace’s equation), provide closed form solutions for single inclusion geometries, providing the electric field distribution in the inclusion and in the matrix. These solutions are used to validate finite element models used to address interactions between inclusions. This discussion addresses 2-D dielectric circular inclusions embedded in a linear polymer matrix. The approach is readily extended to other inclusion geometries such as ellipse, sphere, and ellipsoid (plates and rods).
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