Buckling behavior of additively manufactured cellular columns: Experimental and simulation validation

Lattice structures have been used in a variety of engineering applications in aerospace, automobile and biomedical applications. In this study, the buckling analysis of additively manufactured cellular columns was conducted. The effect of unit cell size and height of the column on the critical buckling load and post-bucking behavior of compressive columns constructed with periodic cubic structure was investigated using experimental and simulation-based studies. The results exhibited that the unit cell size and cellular column height significantly affect the critical buckling load while the total mass, volume fraction, and column dimensions remain the same. The critical buckling load increases with the increase of unit cell size or decrease of cellular column height. The largest unit cell size (8.72 mm) has the maximum critical buckling load, followed by unit cell sizes of 4.74 mm and 2.5 mm, respectively. Moreover, the failure of cellular columns having larger height-to-width (h/w) ratio, happens due to global buckling, whereas, local bucking dominates for smaller h/w ratios. Additionally, it was found that the unit cell size significantly affects on the post-buckling behavior; the samples of larger unit cells failed in a brittle manner and this trend continuously changed from brittle to ductile as the unit cell size reduces.