Influence of N۲ addition in GTAW shielding and backing gas on Super Duplex Stainless Steel properties

Super Duplex Stainless Steels with ۲۵ wt.% chromium, contain both ferrite and austenite phases. They have wide applications in petrochemical industries due to their high strength and corrosion resistance. Arc welding is a common joining method to use, and according to previous studies, fusion welding destroys the duplex microstructure and increase formation of intermetallic phases, resulting in a decrease in corrosion resistance and mechanical properties. Although GTAW is preferable for SDSSs, limited information has been reported. This research shows the effect of adding ۳% N۲ to the shielding and backing gases on the mechanical and corrosion behavior of UNS۳۲۷۵۰. Contrary to previous research, increased distributed ferrite was observed, and mechanical and corrosion behavior were enhanced.

کلیدواژه ها:

Super Duplex Stainless Steels ، Ferrite phase ، Fusion Welding ، GTAW ، Corrosion Resistance ، Mechanical Properties ، Shielding and backing Gas ، UNS۳۲۷۵۰