Influence of multipass pulsed gas metal arc welding on corrosion behaviour of a duplex stainless steel

This work focuses the effect of secondary austenite (γ2) on corrosion resistance of welded joints. The welded joints were obtained by pulsed gas metal arc welding (GMAW-P) with three different heat inputs. Each joint and their respective sub-regions through thickness were characterised by optical microscopy and scanning electron microscopy. The results were correlated with double loop electrochemical potentiodynamic reactivation (DL-EPR) and sulphide stress corrosion tests. The results suggest a good agreement between the DL-EPR and the four point bending tests. It was also verified that the simple presence of γ2 does not necessarily gives rise to loss of corrosion resistance.