Aspect ratio and size effects of a metacomposite with interconnected Y-elements

Abstract

Abstract An investigation on the size effect and aspect ratio is reported herein for a recently designed mechanical metamaterial that manifests perfect auxeticity based on inspiration from a Middle East geometrical pattern by interconnecting rigid Y-elements. An upper bound effective Young’s modulus was acquired by matching the strain energy of the restraining springs within each pair of the Y-elements and the conceptualised continuum strain energy of the entire metamaterial. Results show that the effective Young’s modulus is enhanced with decreasing size of the material. For a fixed amount of metamaterial units, the effective Young’s modulus can be increased by elongating or narrowing the metamaterial structure. This 2D structure is useful for applications which requires preservation of shape while permitting large change in size.