Application of wire and arc additive manufacturing for fabrication of duplex stainless steel product

Abstract

Additive Manufacturing (AM) is a technique where freeform structures are produced by building up material layer by layer. Mostly, AM technologies use powder material as feedstock and different heat sources, which can lead to different problems during the process. WAAM (Wire and Arc Additive Manufacturing) is a technology which has been investigated in the last 30 years, although the first patent was introduced almost 100 years ago. It is a combination of welding and additive manufacturing technologies and one of the potential future application of this technology could be producing the duplex stainless steels. Their excellent corrosion resistance and high mechanical strength make them a favourable choice for oil and gas industrial sectors or off-shore applications. However, they are more difficult to machine than other stainless steels due to their high strength and high work hardening rate, but WAAM could solve some of the problems which occur in their production. Possibility of producing duplex stainless steel product using WAAM is investigated in this paper. Different sets of welding parameters were tested until the most optimal one was chosen, and WAAM product (wall) was made with MIG welding method, using the robotic station.