Study on Arc Welding Processes for High Deposition Rate Additive Manufacturing

Although Additive Manufacturing implementation is rapidly growing, industrial sectors are demanding an increase of manufactured part size which most extended processes, such as Selective Laser Melting (SLM) or Laser Metal Deposition (LMD), are not able to offer. In this sense, Wire-Arc Additive Manufacturing (WAAM) offers high deposition rates and quality without size limits, becoming the best alternative for additive manufacturing of medium-large size parts with high mechanical requirements such as structural parts in the aeronautical industry. WAAM technology adds material in form of wire using an arc welding process in order to melt both the wire and the substrate. There are three welding processes that are mainly used in WAAM: Plasma Arc Welding (PAW), Gas Tungsten Arc Welding (GTAW or TIG) and Gas Metal Arc Welding (GMAW or MIG). This paper studies these processes regarding on their capabilities for additive manufacturing and compares the mechanical properties obtained by the different welding technologies applied in WAAM. Obtained results show the applicability of the technology as an alternative of traditional metallic preforms manufacturing processes, such as casting or forging.