Papyrus-inspired 3D printed stainless steel-based lattice metamaterials with architected stress redistribution for superior mechanical performance

3D printed lattice metamaterials are valued for their lightweight, high strength, and excellent energy absorption. However, widely used conventional lattice topologies such as body-centered cubic (BCC) and face-centered cubic (FCC) structures are inherently limited by severe stress concentration at nodal junctions. Inspired by the triangular-prismatic morphology of papyrus culms, we propose a universal, geometry-driven biomimetic design strategy that redistributes stress from nodes to struts while preserving structural isotropy and lightweight characteristics. Using 316L stainless steel as a benchmark material, this strategy achieves up to 32% improvement in energy absorption, 63% increase in compressive strength, and 59% enhancement in specific modulus compared with conventional lattices. In-situ compression experiments and finite element simulations demonstrate that the proposed design fundamentally alters the deformation mode by suppressing strain localization and promoting homogeneous engagement of lattice cells, thereby delaying premature failure and enhancing load transfer efficiency. Microstructural analyses further confirm pronounced strain redistribution from nodes to struts, supporting a more uniform deformation process. Overall, this work establishes a generalizable biomimetic design principle applicable across different lattice topologies, providing a robust pathway for developing high-performance lattice metamaterials for advanced structural applications and sustainable engineering. Inspired by papyrus culms, this study introduces a geometry-driven lattice design that shifts stress from nodes to struts by using polygonal strut cross-sections, reducing strain localization while maintaining isotropy. Laser 3D-printed 316L stainless-steel lattices show up to 32% higher energy absorption, 63% greater compressive strength, and 59% higher specific modulus, with more uniform deformation and delayed failure.