Corrosion resistance properties of duplex stainless steels welded joints

The corrosion resistance properties of duplex stainless steels (DSS) welded joints are investigated by a new method using samples in small size based on the critical pitting temperature (CPT) obtained in the previous experiments. The results show that the Shielded Metal Arc welding process has a significant effect on the corrosion performance of DSS. Pits preferentially occur either in the weld metal or in the heat affected zone. The corrosion resistance performance of DSS is closely related to the austenite and ferrite ratio. The surface condition (roughness) of corrosion test sample has a pronounced influence on the pitting resistance of the base metal. In general, the rougher the surface, the poorer the pitting resistance, and the lower the critical pitting temperature.