Microstructural effects on overall dynamics of composites: an analytical method via spatiotemporal nonlocal model.

With the development of composite materials, especially metamaterials, spatiotemporal nonlocal continuum models for overall dynamics of composites have made enormous progress in recent years, which naturally contain intrinsic space and time scales, and provide a favorable platform to explore the microstructural effects. In this paper, the microstructural effects on the overall dynamics of unidirectional composites are investigated via a mechanism-based spatiotemporal nonlocal model. We first identify the intermediate quantities including the intrinsic length and nonlocal attenuation function and explore their correlations to the microstructural parameters. Then analytical solutions of the mechanism-based spatiotemporal nonlocal model are derived to manifest the overall dynamics of composites. Finally, the microstructural effects on the dispersion relation, the dynamic Green's functions and the dynamic responses in the space-time domain are quantitatively depicted by explicit expressions. Since the intrinsic length and nonlocal attenuation function have always been two fundamental issues in nonlocal continuum theories, the results give some insights into their physical mechanisms in the context of composites. [ABSTRACT FROM AUTHOR]