Investigation of energy absorption for 3D printed auxetic tubular structures

Purpose With the growing demand for sustainable and optimized designs, three-dimensional (3D)-printed structures have gained increasing prominence in engineering applications, particularly because of their enhanced mechanical performance in energy absorption. This study aims to experimentally characterize and compare the energy absorption behavior of three auxetic cylindrical 3D-printed structures. Design/methodology/approach Three distinct 3D-printed structures were developed: two axisymmetric auxetic structures (RA1 and R2A) with re-entrant (2D) auxetic geometries and a third structure (R1NA) with periodicity in both axial and radial directions, exhibiting a fully 3D re-entrant auxetic form. All structures were fabricated using fused deposition modeling with polylactic acid. Their mechanical performance was evaluated through experimental characterization, focusing on key energy absorption metrics, including specific energy absorption and crush force efficiency. Findings The experimental results demonstrated that the two axisymmetric auxetic structures exhibited significantly higher specific energy absorption and CFE compared to the lattice structure. Their superior performance is primarily attributed to a more efficient crushing phase characterized by a nearly constant crushing force. Originality/value This study provides novel insights into the mechanical behavior of cylindrical re-entrant structures under compression. The findings of this study contribute to the advancement of lightweight energy-absorbing structures by demonstrating the advantages of auxetic geometries over conventional lattice designs. These results have potential applications in engineering fields requiring enhanced energy absorption capabilities.