Investigation of ballistic performance of selective laser-melted AlSi10Mg alloy lattice structures by experimental and numerical studies

Metal alloys used in armor structures, a crucial component in the defense sector, are typically produced in plate form. However, the layer-by-layer production capability of additive manufacturing now allows for the creation of alloys with highly complex geometries. Among these, lattice structures have gained significant attention due to their high specific strength and energy absorption capabilities. Despite this interest, the ballistic response of these structures has not been thoroughly investigated. This study explores the ballistic behavior of AlSi10Mg alloy lattice structures manufactured using selective laser melting (SLM). The ballistic perforation performance of face- centered cubic (FCC) and diamond lattice structures was compared with that of bulk plate structures produced by SLM, all with the same design volume. The influence of the number of layers on ballistic performance was also investigated by testing diamond structures with 2, 3, and 4 layers. Additionally, numerical ballistic simulations were performed using Johnson-Cook (J-C) material and damage parameters optimized through Response Surface Methodology (RSM). The comparative analysis revealed that diamond lattice structures demonstrated superior energy absorption compared to FCC structures in ballistic tests. Experimental and numerical analyses showed that bulk structures outperformed the tested lattice structures in terms of overall ballistic resistance. This conclusion is based on the selected lattice structures and an initial projectile velocity of approximately 500 m/s. Among the lattice structures, the 3-layer diamond structure exhibited the highest experimental ballistic energy absorption. Finally, the energy absorption values estimated from numerical ballistic simulations were within approximately 10 % of the experimental measurements.