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arXiv · 2411.15013

Static and dynamic analysis of auxetic three-dimensional curved metamaterials in both axial and circumferential directions

Abstract

Metamaterials can enable unique mechanical properties based on their geometry rather than their chemical composition. Such properties can go beyond what is possible using conventional materials. Most of the existing literature consider metamaterials in Cartesian coordinates with zero curvature. However, realistic utilization of meta-structures is highly likely to involve a degree of curvature. In this paper, we study both the effective static and dynamic properties of metamaterials in the presence of curvature. To capture the effect of curvature on the static behavior of our metamaterial, we calculate the effective Poisson's ratio of the metamaterial in the presence of curvature. We conduct our analysis on three-dimensional metamaterials with varying effective Poisson's ratio. We observe a significant change in the values of the effective Poisson's ratio of the metamaterial duo to curvature. To capture the effect of curvature on the dynamics of our metamaterials, we calculate dispersion curves of curved metamaterial at different circumferential directions. We show both numerically and experimentally the change of the dynamic behavior of auxetic metamaterial from attenuation to transmission and vice-versa due to curvature. Our findings underscore the importance of curvature in both static and dynamic analysis of metamaterial design and could provide the means to guide practical implementations of metamaterials for functional use.

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Mohamed Roshdy, Osama R. Bilal. 2024-11-22. Static and dynamic analysis of auxetic three-dimensional curved metamaterials in both axial and circumferential directions. https://doi.org/10.1016/j.eml.2024.102285

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