Compressive Behavior of 3D-Printed Stiffened Bioinspired Tubular Metamaterials

Abstract

This study proposes innovative bioinspired tubular metamaterial structures modeled after the zigzag patterns commonly found in natural systems. The straight, curved zigzag and their symmetrical counterparts serve as inspiration for the design of a novel biomimetic tube. To enhance the mechanical performance of these tubes, circumferential stiffeners are incorporated, varying in both quantity and arrangement. Various samples are fabricated using additive manufacturing, and experimental testing combined with finite-element analysis is employed to assess deformation behavior, energy absorption (EA), specific EA (SEA), and effective Young's modulus (E_eff). Results demonstrate that the addition of stiffeners significantly enhances the EA capacity and deformation behavior by varying the overall Poisson's ratio and enhancing stiffness. Straight zigzag tubes exhibit the highest stiffness, while symmetric curved zigzag tubes show up to a 33% improvement in effective modulus with stiffener integration. Nonsymmetric configurations enhanced by stiffener integration demonstrate superior EA up to 52%. Stiffeners enhance SEA by up to 42% in curved zigzag tubes. The parametric study further emphasizes the critical role of geometric parameters in optimizing mechanical performance. These results provide valuable insights for designing advanced tubular structures with high EA for a variety of applications.