Laser Joining of Stellite and Stainless Steel

Stellite® is a CoCrW-based alloy which has been applied for hard phase coating to enhance corrosion and wearing properties. For practical manufacturing, it is hard to extrude complicated alloy wires. The Stellite alloy wire was generally extruded in powder slurry and further formed by sintering. The long wire is fabricated by resistance butt welding with limited bonding strength. In this study, we tried to do the similar joining by laser welding of Stellite 6 wire segments and by dissimilar welding of Stellite 6 wire with stainless steel wire, both with Ar protection and in the glovebox with Ar atmosphere. We compared two kinds of lasers, femtosecond laser and continue wave fiber laser. The femtosecond laser welding of Stellite 6 and steel wires displays a 53% joining efficiency with a bond strength to 400 MPa. The welding in the glovebox displays the further improvement of mechanical properties. The microstructure and mechanical properties as well as anti-corrosion properties are characterized.