Improvement of pitting corrosion resistance of wire arc additive manufactured duplex stainless steel through post-manufacturing heat-treatment

Abstract In this work, the unbalanced phase ratio and the adverse secondary austenite generally discovered in the wire arc additive manufactured duplex stainless steel were modified using post-manufacturing heat-treatment. The pitting corrosion resistance was significantly improved, which could be comparable to the hot-rolled 2205 duplex stainless steel after the heat-treatment at 1300 °C for an hour. The crystalline and microstructural investigation revealed that the striking corrosion resistance of the 1300 °C heat-treated sample was the result of the balanced phase ratio, the non-existence of chromium nitride, the 〈111〉//X texture of austenite, the decrease of crystalline defect density and the recrystallization of austenite.