Revealing the interrelation between combined process parameters and geometrical deviations for building dimensionally stable and dense thin-walls using Laser Directed Energy Deposition

The geometric stability of thin-wall structures built by Laser Directed Energy Deposition (LDED) depends on the process parameters. This paper presents the interrelation between combined LDED process parameters and geometrical deviations of thin-walls. The thin-walls are built at different combinations of laser energy per unit length (LEL) and powder feed rate per unit length (PFL) and the deviation in geometric parameters are investigated. The average wall height increases with an increase in LEL and PFL, and the average wall width increases with an increase in LEL. The wall height deviation increases when PEL is increased and the deviation in wall width (with respect to single-track width) increases with LEL and reduces with an increase in PFL. A process window with LEL and PFL of 60–100 J/mm and 0.002–0.008 g/mm, respectively, yielded dimensionally stable and dense thin-walls. The study paves the way for developing large-scale thin-wall components using LDED.