Rapid L-PBF Printing Of IN718 Coupled With HIP-Quench: A Faster Approach To Combine Manufacturing And Heat Treatment In A Nickel-Based Alloy

Applying Hot Isostatic Pressing to additively manufactured samples is a key factor in drastically reducing the printing time. In this work, L-PBF IN718 was printed with two different strategies aiming to reduce the leading time drastically. The first consisted of printing a 1 mm dense shell of material, leaving the powders inside completely loosened. The second used two different printing speeds, a slower one for the external shell and a faster one for the core. The two strategies allowed a time saving of 60 and 45 %, respectively. A further time optimization consisted in performing the following HIP process at the same temperature as the annealing treatment to get full densification and the correct microstructure at the same time thanks to a final fast gas quench. The obtained microstructures were assessed morphologically using traditional electronic microscopy and EBSD. Furthermore, the shell-core interface was assessed via micro-indentations.