Comparison of laser metal deposition of Inconel 718 from powder, hot and cold wire

Abstract

The present paper details first results on laser metal deposition with a new direct diode laser head which allows for coaxial feed of powder, cold- and hot wire material in a single system. The three process variants are compared for laser metal deposition of Inconel 718. The surface appearance, integrity and microstructure of the specimens built with the LMD head are investigated. The presence and removal of the deleterious Laves phase which is detrimental to the mechanical properties is investigated. The results indicate that the new diode laser head allows for a direction-independent LMD process with low oxygen take-up and high surface quality.