Wire arc additive manufacturing of light metals: From experimental investigation to numerical process simulation and microstructural modeling

Additive manufacturing (AM) is the latest type of manufacturing technology in which layers of materials are built up using a predefined geometry. It has witnessed substantial growth both in terms of techniques and materials in recent years. In the previous chapters, various techniques for metal additive manufacturing have been described along with their current standards and practices. In this chapter, we focus our attention on wire arc additive manufacturing (WAAM), which is a type of directed energy deposition (DED) AM process as outlined in ISO/ASTM 52900:2015 [1]. In WAAM, an electric or plasma arc is used as the heat source to melt a wire feedstock, which results in fusion with the previously deposited layers, thus building up material in the process. Compared to other AM methods, the advantages of WAAM are a higher productivity rate, the ability to manufacture large components, and the ready availability, lower cost, and handling safety of the welding wire compared to the powder feedstock. Applications of WAAM already exist in the automotive, space and aeronautics, and shipping industries, where the use of light metals is common.