Topology-driven mechanical performance in architected cellular materials: insights from bioinspired glass sponge...

Architected lattice materials inspired by biological structures are frequently described as bioinspired, yet the underlying functional principles governing their mechanical response are not always explicitly isolated. The hexactinellid spongeEuplectella aspergillumexhibits a distinctive skeletal organization based on a periodic square unit subdivided into four sub-squares, where two opposite regions are reinforced by paired diagonal struts while the remaining corners remain non-reinforced. This alternating reinforcement pattern introduces spatial heterogeneity in stiffness and connectivity at the unit-cell scale. While related geometries have been examined under compression and bending, their tensile elasto-plastic behavior and the specific mechanical role of this architectural coupling remain insufficiently understood. In this study, we isolate and quantify the contributions of (i) diagonal reinforcement and (ii) spatial cell alternation under uniaxial tension. PLA-based lattice variants were fabricated using fused filament fabrication to decouple these structural variables and were benchmarked against the full EA-sponge derived topology. Quasi-static tensile experiments, supported by linear elastic finite-element analysis, demonstrate that all configurations exhibit stretch-dominated elastic scaling. However, significant differences emerge in post-yield behavior. Fully plain and fully reinforced lattices show early strain localization and structurally brittle fracture modes, whereas alternating architectures promote stress redistribution and delay the formation of continuous failure bands. The EA-sponge topology, characterized by its checkerboard alternation and geometrically offset diagonals, exhibits the most stable structural elasto-plastic response, combining stiffness retention with progressive, non-catastrophic fracture behavior. These findings demonstrate that tensile performance is governed primarily by structural connectivity and spatial organization rather than relative density or material properties alone, establishing a topology-driven design principle derived from biological organization.