Key points are not available for this paper at this time.
The introduction of stays in collinear unit cells (UCs) significantly improves their load-bearing capacity with negligible weight increase. The mechanical performance of stayed UCs produced by material extrusion (MEX) additive manufacturing (AM) was optimized under uniaxial compression by adjusting geometric parameters to tune the buckling behavior. Key parameters studied include overall dimensions, imperfections, intersection configurations, and length-to-width ratios. This study focuses on 3D printing and mechanical testing. Printability tests confirmed consistently high quality across parameter variants, establishing a reliable and manufacturable design range for the UCs. Compression tests show a positive correlation between ultimate stress and relative density, with the highest strengths obtained for smaller UCs. Additionally, intersection modifications, specific imperfections, and orientation provide additional gains in ultimate load. Beyond load bearing, energy absorption is advanced by the postbuckling behavior, which allows for significant end-shortening while preventing abrupt failure. Structural weakness is localized at the junctions between the diagonal stays and the main cross. Even when these nodes are damaged, the structure retains residual load-bearing capacity. These findings provide experimental data supporting the optimization of stayed lattice structure for maximum load-bearing capacity and energy absorption capability, which is the groundwork for tunable 2D- and 3D-lattice designs.
Ou et al. (Mon,) studied this question.