Ballistic performance of additive manufacturing metal lattice structures

For the purpose of elucidating the destruction and energy absorption mechanisms of lattice structures during ballistic impacts, this study explored the behavior of two additively manufactured metal lattice structures (BCC and BCCZ) under quasi-static/dynamic compression and ballistic impact through experiments and numerical simulations. Both structures exhibited typical stress-strain behaviors during quasi-static compression, with stress plateauing after reaching yield strength and then sharply declining upon failure. The vertical struts in the BCCZ structure resulted in higher yield strength but lower normalized failure strain compared to the BCC structure, especially at higher strain rates. The ballistic limit of the BCC lattice sandwich target plate at 199 m/s and that of the BCCZ lattice sandwich target plate at 195 m/s. At an impact velocity of 207 m/s, the energy absorbed by the BCC lattice structure itself (498 J) was marginally lower than that absorbed by the BCCZ structure (505 J). The BCC structure, characterized by lower stiffness and yield strength but a larger failure strain, absorbed energy primarily through greater deformation during impact. In contrast, the BCCZ structure, with a smaller failure strain, depended on its higher stiffness and yield strength for energy absorption.