Hot-wire GTAW cladding: inconel 625 on 347 stainless steel

Gas tungsten arc (GTA) cladding has been widely applied in surface modification and repairing. In this study, low current gas tungsten arc welding (GTAW) cladding in the range of 60 to 100 A was performed with resistively heating hot-wire filler Inconel alloy (IN625) on the 347 stainless steel substrate. A 70 A or more primary current can be used to clad a continuous and uniform layer on the substrate by resistively heating the wire and varying the torch angle. Lower dilution and higher contact angle were observed for lower current clad. An analytical model has been used to understand the resistively heating hot-wire effect. The microstructure of the clad bead and the substrate was analyzed. A heat-affected zone (HAZ) cracking was observed in the higher range of primary current. An EDX analysis was performed to reveal iron (Fe) elemental dilution and elemental segregation.