Multi‐Objective Optimization of a Novel Auxetic Tubular Re‐Entrant Structure (ATRS) Using 3D Printing and Statistical Design

ABSTRACT This study presents, a comprehensive investigation into the failure behavior and parametric optimization of novel 3D‐printed Auxetic Tubular Re‐entrant Structures (ATRS), using an integrated experimental–numerical framework. Compression tests are performed on four ATRS designs featuring different unit cell angles, thicknesses, and widths to confirm simulation accuracy and evaluate mechanical performance. Excellent agreement is observed between experimental and simulation results, capturing both the initial linear response and the nonlinear buckling behavior. The simulations revealed exceptional auxetic responses and showed how geometric parameters govern stress localization and failure initiation. Reduced unit cell widths led to earlier buckling owing to a smaller load‐bearing area and increased soft mode activation, whereas larger angles raised buckling forces but triggered instability sooner. Also, energy absorption capacity rose significantly with increases in unit cell width, angle, and thickness, reaching as much as four times higher in thicker samples. According to Response Surface Methodology (RSM) and Analysis of Variance (ANOVA), thickness and width are the primary parameters influencing buckling force, stiffness, and energy absorption, with thickness having the greatest impact. These findings facilitate accurate predictive modeling of ATRS mechanical behavior driven by geometric design and offer new pathways for designing damage‐tolerant structures with tunable mechanical responses.