Production of aluminum alloy cellular structures and mechanical characterization through compression and hardness tests

In this study, the mechanical behavior of aluminum alloy AA6082 cellular structures produced via the lost-PLA replication method was analyzed. This cost-effective and straightforward manufacturing technique involves the manufacturing of a PLA model using 3D printing, which is subsequently transformed into a metallic structure through casting techniques. The produced structures exhibited a well-defined morphology, high surface quality and a strong correlation between experimental weight and theoretical values, confirming the reliability of the replication process. Compression tests, performed on portions of the structures due to technical limitations, revealed a mechanical response characterized by an initial linear elastic phase, a plateau and a final densification phase, during which an abrupt load increase was observed. Specific energy absorption (SEA), computed from the nominal stress–strain curve and referred to the external specimen volume, reached about 26 J/cm 3 for the tested cut-out specimens (average external volume ≈ 1.29 cm 3 , mass ≈ 1.4 g). These results demonstrate the reproducibility of the manufacturing process and the reliable mechanical response of Lost-PLA aluminum cellular structures intended for lightweight energy-absorbing components, with potential relevance for structural protection in hydrogen-powered mobility systems.