THE INFLUENCE OF BUILD PARAMETERS ON THE COLLAPSE BEHAVIOUR OF A HIGHLY POROUS RANDOM OPEN-CELL LATTICE 3D PRINTED IN IN718 ALLOY

Nowadays, additive manufacturing (AM) is revolutionizing production, enabling the rapid fabrication of objects in various sizes and shapes, including complex designs such as metallic foam, while significantly reducing material waste. This paper examines the effect of 3D printing parameters (Set A and Set B) on the mechanical behavior of a highly porous random open-cell lattice (HPROCL) in IN718 alloy produced by selective laser melting (PBF-LM). The modified build parameters were applied to reduce manufacturing cost and time while minimizing micro porosity in ligaments by increasing exposure time through reduced laser scanning speed or higher energy density. Furthermore, the researchers investigate ligament deformation, key stages of collapse and stability, its role in impact resistance, and how microstructure influences the hardening behavior of the HPROCL across a wide range of strain rates. The SEM-EDS elemental distribution analysis carried out on the tested specimens enabled to conclude that the foam printed with modified parameters (Set B) contained a lower content of the Laves phase and a higher amount of the δ-phase, which led to an increase in both static and dynamic compressive behavior of HPROCL in IN718 alloy.