Optimizing process for pulsed laser additive manufacturing of nickel-based single crystal superalloy

Abstract

The relationship between pulsed laser processing parameters and epitaxial growth of alloy is essential to additive manufacturing technology in repairing and manufacturing nickel-based single crystal (SX) superalloys. In this paper, orthogonal experiments of Laser Direct Energy Deposition (DED-L) process have been designed to optimize the process for the epitaxial growth of the SX superalloy. The relationship between process parameters and epitaxial growth of SX superalloy is established in a radar map, which shows that low laser power, pulse width and powder feeding rate help epitaxial growth in the DED-L process. It is implied that increasing the powder feeding rate value in the process range decreases the epitaxial growth rate of the molten pool and increases manufacturing efficiency. The size of the cladding layer width is greatly influenced by laser power (reached 44%) and pulse width (reached 38%). The deposited heigh of the cladding layer is mainly influenced by pulse width (reached 45%) and powder feeding rate (reached 42%). The process parameters have a similar level (approximately 33%) of influence on the powder using efficiency.