Heat-affected zone ferrite content control of a duplex stainless steel grade to enhance weldability

Abstract Duplex stainless steels (DSS) have a microstructure consisting of 50% ferrite α and austenite γ. This two-phase provides the duplex with attractive mechanical corrosion properties. However, is very dependent on heat treatment chemical composition. During welding process, temperature reached in heat-affected zone (HAZ) retransforms into ferrite. Due to high cooling rates, only part retransformed austenite. tends modify 50/50 phase equilibrium. The rate linked not input but also thickness welded plates. Most standards limit content range from 30 70%. 70% for HAZ may be difficult obtain especially heavy plate thicknesses. To maximum HAZ, grade nitrogen nickel within 2205 composition range, called Arctic 2205, was developed. paper will provide details measurement by metallographic method results obtained industrial welds showing low stable HAZ. Mechanical properties these at reported, pushing limits use − 50 °C (− 58 °F) down 100 148 °F).