Nickel based alloys are used in different applications of the industries like power generation or the petro chemical industry. Out of the variety of these protection methodologies, weld overlay with ERNiCrMo-3 (Alloy 625) has proven to be the most widely accepted. This paper describes weld overlays of ERNiCrMo-3 (Alloy 625) with the welding methods GMAW Pulse, CMT, Tandem, CMT Twin, TIG cold wire, TIG hot wire and Laser Hybrid. The investigation of these probes includes the Fe dilution of the base material, the distribution of the Fe concentration through the weld overlay, and further on the welding speed and weld deposition rate.