Design and Compressive Characterization of Developed Lattice Structures for Lightweight Applications: A Preliminary Study

Lattice structures offer high lightweight efficiency and tunable mechanical performance, making them promising for applications requiring effective load bearing and controlled deformation. In this study, two new lattice architectures, namely the Hexagonal hub lattice structure (HH) and P-surface-based circular junction lattice structure (PCJ), were proposed, and their compressive behaviors were experimentally investigated. A conventional octet-truss lattice structure (OT) and body-centered cubic lattice structure (BCC) were employed as representative stretch- and bending-dominated references, respectively. The hourglass re-entrant lattice structure (HR) was additionally included for comparison because of its distinctive compressive deformation characteristics. To ensure a consistent comparison, all architectures were designed with an identical unit-cell size and approximately equal material volume and fabricated from polylactic acid using material extrusion. Compression tests revealed distinct load-bearing and deformation characteristics depending on the lattice geometry. HH and PCJ exhibited stretch-dominated-like characteristics comparable to OT and showed relatively high compressive strengths. Among the investigated architectures, HH exhibited the highest compressive strength while maintaining a relatively stable post-peak response. Deformation observations further revealed diagonal shear-band-like deformation in HH, PCJ, and OT, whereas HR exhibited inward lateral contraction associated with its re-entrant geometry and relatively early densification. BCC underwent progressive layer-by-layer collapse without pronounced diagonal localization. These results demonstrate that tailoring lattice geometry can effectively control load-transfer and collapse mechanisms, providing a design strategy for lightweight structures requiring high compressive load-bearing capability and controlled deformation behavior.