Additive Manufacturing with Stellite 6 Metal-Cored Wire by Gas Tungsten Arc Welding and Plasma Arc Welding Methods

Metal-cored wires offer an opportunity to manufacture highly alloyed materials in the form of a tubular wire which may include any compatible powder alloy. These wires can be used with Wire and Arc Additive Manufacturing methods such as GTAW and PAW. These methods use a lower cost, and less complex heat source compared with Laser and Electron-Beam Processes. In this study, Stellite 6 metal-cored wire was utilized with GTAW to determine printing parameters. However, initial experiment showed that manufacturing thin walls with <3.5 mm thickness would not be possible with continuous weld beads, resulting in poor repeatability and geometrical defects. Therefore, the Coordinated Heat and Feed (CHF) printing strategy was developed and validated to address these issues. Furthermore, a PAW system was adopted in place of GTAW for an increased flexibility. However, preliminary tests with the CHF method resulted in high amount of oxidation although the geometrical features were improved.