Geometrically tailored 3D-printed HCC-PW lattice structures for deformation-regulated energy absorption under compression

Abstract

The crushing performance of 3D-printed thin-walled lattices depends on the coordination between load transfer and structural deformation. This study investigates cell-wall bending, global twist, and their combination in polylactic acid (PLA) hollow cylindrical cross-plate wall (HCC-PW) lattice structures. Eight configurations were fabricated by fused deposition modeling and investigated through quasi-static compression tests and finite element simulations. Specific energy absorption (SEA), mean crushing force (MCF), and crushing force efficiency (CFE) were evaluated up to engineering strains of 0.5 and 0.6. Moderate bending promoted progressive wall bending and rotational folding, providing a favorable balance between energy absorption and load-bearing response. At the strain limit of 0.6, the moderately bent configuration B2 achieved an SEA of 18.17 J g−1, an MCF of 12.73 kN, and a CFE of 0.81. A 10° twist produced a slightly higher CFE than the baseline with comparable SEA and MCF, whereas a 20° twist was associated with inclined collapse and reduced axial load-bearing capacity. The coupled configurations B1T10 and B2T10 exhibited lower SEA and MCF than their corresponding single-bending configurations, indicating that the benefits of the individual modifications did not accumulate in these combinations. These principal performance relationships persisted when the strain limit increased from 0.5 to 0.6. The simulations provided qualitative support for the deformation-based interpretation. The findings highlight the importance of coordinating bending and rotation when tailoring HCC-PW energy absorbers under the investigated quasi-static conditions.