Effect of brief heat treatments performed between 650 and 850 °C on corrosion behaviour of a lean duplex stainless steel. (May 2015)

• Record Type: Journal Article
• Authors: Zanotto, F.; Grassi, V.; Merlin, M.; Balbo, A.; Zucchi, F.
• Is Part Of: Corrosion science. Volume 94(2015)
• Page Start: 38
• Page End: 47
• Publication Date: 2015-05
• Subjects: A. Stainless steel -- B. Polarisation -- C. Pitting corrosion -- C. Intergranular corrosion; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2015.01.035
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: Brief-time heat treatments within 650–850 °C were performed on LDX2101®. The microstructural modifications due to the performed heat treatments were analysed. Electrochemical tests were conducted to evaluate the effect on LDX2101® corrosion resistance. Susceptibility to pitting and IGC strongly increased for certain time–temperature conditions. A correlation between microstructural modifications, E pitt. and DL-EPR test results was observed. Abstract: In this study the effect of brief heat treatments within the 650–850 °C range on pitting corrosion and intergranular corrosion resistance of a lean duplex stainless steel was investigated. Pitting potentials ( E pitt .) and critical pitting temperature (CPT) were determined in sodium chloride solutions. The degree of sensitisation (DOS) to intergranular corrosion (IGC) was evaluated by DL-EPR method application. The most critical treatment conditions were observed at 650 °C and at 750 °C. A recovery of the pitting and IGC resistance of the studied lean duplex was noted at 850 °C due to the redistribution of chromium towards the depleted zones.