Corrosion Behavior of Duplex and Lean Duplex Stainless Steels in Pulp Mill

Abstract

The cyclic potentiodynamic polarization behavior of duplex stainless steel (DSS) and lean duplexstainless steel (LDSS) was studied in white and green liquors froma pulp processingplant. The corrosion behavior in industrial and also synthetic liquor was compared. The polarization curves of the duplex steels in synthetic white liquor were shifted to lower potentials and higher current densities in relation to the steel in industrial white liquor, which proved to be less aggressive to the duplex steel. The duplex steels also showed the highest values of transpassive potential in industrial white liquor compared to synthetic liquor. Cold and hot rolled duplex and lean duplex steels in green liquor showed the lowest values of transpassive potential.

Keywords

• Duplex stainless steels
• Polarization
• Alkaline corrosion
• Pulp and paper industry