Analysis of the Deformation Behavior and Mechanical Properties of Slit‐Perforated Auxetic Metamaterials. Issue 1 (14th December 2018)

• Record Type: Journal Article
• Authors: Mizzi, Luke; Grima, Joseph N.; Gatt, Ruben; Attard, Daphne
• Is Part Of: Physica status solidi. Volume 256:Issue 1(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-12-14
• Subjects: auxetics -- mechanical metamaterials -- negative Poisson's ratio -- perforated systems; Solid state physics -- Periodicals; Solids -- Periodicals; Atomic structure -- Periodicals; 530.41
• DOI: 10.1002/pssb.201800153
• Languages: English
• ISSNs: 0370-1972

Abstract

Abstract : Perforated systems constitute one of the most important classes of mechanical metamaterials. In this work, two types of "I"‐shaped slit perforation patterns are proposed which may be used to design perforated systems that mimic the deformation mechanisms of a variety of re‐entrant and anti‐tetrachiral honeycomb systems. Using finite element analysis, it is shown how these systems have the potential to exhibit a large spectrum of negative Poisson's ratios, ranging from extremely negative to zero, which are retained over a wide tensile strain range. A detailed analysis of the deformation behavior of these systems is also presented along with a comparison of the changes in overall expansion and Poisson's ratios of both systems observed upon loading with those predicted by previously formulated theoretical models of re‐entrant and anti‐tetrachiral systems. It is hoped that this work will be of considerable aid in the efforts of scientists to understand the underlying principles governing the production of auxetic mechanical metamaterials through the use of perforations and also stimulate further research on how these and similar mechanisms may be implemented in perforated systems to design other metamaterials with anomalous mechanical properties. Abstract : Systems with I‐shaped slit perforations can be made to mimic either a re‐entrant or an anti‐tetrachiral system, depending on the slit orientation. By varying the profile of the slits and their separation, it is possible to obtain a wide spectrum of negative Poisson's ratios, ranging from extremely negative to near‐zero, which are retained over large strains.