Heat Treatment Design for IN718 by Laser Metal Deposition with High Deposition Rates: Modeling, Simulation, and Experiments.

Laser metal deposited processed Ni-based superalloy IN718 is characterized by elemental micro-segregation, anisotropy, and Laves phases due to the rapid solidification and therefore needs homogenization heat treatment to achieve comparable properties of wrought alloys. In this article, we report a simulation-based methodology to design heat treatment IN718 in a laser metal deposition (LMD) process by using Thermo-calc. Initially, the finite element modeling simulates the laser melt pool to compute the solidification rate (G) and temperature gradient (R).

Laser Directed Energy Deposition of an AlMgScZr-Alloy in High-Speed Process Regimes.

Aluminum-magnesium-scandium-zirconium (AlMgScZr) alloys need to be rapidly cooled from the liquid state to obtain a high degree of solute supersaturation that helps to exploit the precipitation hardening potential of the material. While AlMgScZr alloys have been successfully used in laser powder bed fusion (LPBF) processes, there has been little research in the field of laser directed energy deposition (DED) of the material. The limited previous studies have shown that the performance of AlMgScZr parts fabricated with DED only reached about 60% of that of the parts fabricated with LPBF.