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arXiv · 2212.07360

An Investigation of Reconfigurable Magnetomechanical Metamaterials

Abstract

In this work, an experimental investigation of an accordion-like system with embedded magnetic inclusion is carried out. It is shown that the way that this structure deforms when subjected to an external magnetic field depends on the magnetic moment of the embedded magnets and the length of the arms. Stacking of the accordion-like system leads to the formation of hexagonal honeycombs that can have a negative, zero, and positive Poisson's ratio. Variation in the configuration attained depends on the relative positioning of the magnetic inclusion and the applied magnetic field. In particular, one of the hexagonal honeycomb arrangements was able to switch between a conventional and a re-entrant configuration upon the reversal of the external magnetic field. For all structures considered, the dimensions can be controlled through the external magnetic field allowing for a high degree of turnability. Furthermore, their behaviour can be altered in real time. The practical implications of the results are of interest since they indicate that these structures can be adopted in numerous applications, such in the design of scaffoldings for deployable structures, actuators, variable pored sieves, and sound proofing systems.

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R. Galea, P. -S. Farrugia, K. K. Dudek, L. Zammit Mangion, J. N. Grima, R. Gatt. 2022-12-14. An Investigation of Reconfigurable Magnetomechanical Metamaterials. https://doi.org/10.1002/pssb.202200420

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