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arXiv · 0811.2387

The homogenization of orthorhombic piezoelectric composites by the strong-property-fluctuation theory

Andrew J. Duncan·Tom G. Mackay·Akhlesh Lakhtakia
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Abstract

The linear strong--property--fluctuation theory (SPFT) was developed in order to estimate the constitutive parameters of certain homogenized composite materials (HCMs) in the long--wavelength regime. The component materials of the HCM were generally orthorhombic $mm2$ piezoelectric materials, which were randomly distributed as oriented ellipsoidal particles. At the second--order level of approximation, wherein a two--point correlation function and its associated correlation length characterize the component material distributions, the SPFT estimates of the HCM constitutive parameters were expressed in terms of numerically--tractable two--dimensional integrals. Representative numerical calculations revealed that: (i) the lowest--order SPFT estimates are qualitatively similar to those provided by the corresponding Mori--Tanaka homogenization formalism, but differences between the two estimates become more pronounced as the component particles become more eccentric in shape; and (ii) the second--order SPFT estimate provides a significant correction to the lowest--order estimate, which reflects dissipative losses due to scattering.

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Andrew J. Duncan, Tom G. Mackay, Akhlesh Lakhtakia. 2008-11-14. The homogenization of orthorhombic piezoelectric composites by the strong-property-fluctuation theory. https://doi.org/10.1088/1751-8113%2F42%2F16%2F165402

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