Bilinear stiffness and bimodular Poisson's ratio in cylindrical sinusoidal lattices through topology morphing

Sundararaman, Venkatesh; O'Donnell, Matthew P.; Chenchiah, Isaac V.; Weaver, Paul M.

Abstract

Bilinear elastic behaviour allows structural designs to respond in either a stiff or compliant manner depending on the load. Here a cylindrical sinusoidal lattice structure is described that stiffens beyond a certain load. When subjected to axial compression, the lattice can undergo a topological transformation by forming contact connections. This topology change involves a transition from rectangular-like unit cells to kagome-like unit cells, associated with an approximately fourfold increase in stiffness. The lattice exhibits negative Poisson's ratio with a step-change from ≈−0.66 to ≈−0.23 prior to and during contact formation, respectively. After contact formation, it displays a nonlinear Poisson's ratio behaviour. The mechanics underpinning these behaviours are analysed using a combination of experiments and numerical modelling. A comparison with similar planar lattices reveals the effect of the global topology of the lattice (e.g. planar, cylindrical) on the unit cell-level topology morphing. The proposed topology-morphing cylindrical sinusoidal lattice introduces new design possibilities in the application-rich context of tubular structures with nonlinear mechanical properties.

• Journal Article Type: Article
• Acceptance Date: Apr 25, 2024
• Online Publication Date: May 3, 2024
• Publication Date: Jun 30, 2024
• Deposit Date: May 6, 2024
• Publicly Available Date: May 23, 2024
• Journal: Materials and Design
• Print ISSN: 0264-1275
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 242
• Article Number: 112980
• DOI: https://doi.org/10.1016/j.matdes.2024.112980
• Public URL: https://uwe-repository.worktribe.com/output/11977598
• Additional Information: This article is maintained by: Elsevier; Article Title: Bilinear stiffness and bimodular Poisson's ratio in cylindrical sinusoidal lattices through topology morphing; Journal Title: Materials & Design; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.matdes.2024.112980; Content Type: article; Copyright: © 2024 The Author(s). Published by Elsevier Ltd.