Effect of spinodal decomposition on the pitting corrosion resistance of Z3CN20.09M duplex stainless steel. Issue 4 (13th November 2017)

• Record Type: Journal Article
• Authors: Chen, Yuefeng; Chen, Xudong; Dai, Xin; You, Ye; Yang, Bin
• Is Part Of: Materials and corrosion. Volume 69:Issue 4(2018)
• Page Start: 527
• Page End: 535
• Publication Date: 2017-11-13
• Subjects: duplex stainless steel -- pitting corrosion -- spinodal decomposition; Materials -- Periodicals; Metals -- Periodicals; Corrosion and anti-corrosives -- Periodicals; 620.1122305
• DOI: 10.1002/maco.201709738
• Languages: English
• ISSNs: 0947-5117

Abstract

Abstract : The microstructural characterization and pitting corrosion behavior of Z3CN20.09M duplex stainless steel were investigated by TEM, potentiodynamic polarization, and electrochemical impedance spectroscopy after thermal aging at 475 °C for 0, 500, 1000, 2000, and 3000 h. The results showed that the ferrite in the steel decomposes into coherent Cr‐rich, Fe‐rich, and G phases. No any precipitates were found in the austenite during the thermal aging process. It is revealed that the pitting resistance of this steel has a negative relationship with increasing aging time and the priority nucleation position changes before and after the thermal aging process. The composition fluctuation region adjacent to the G phase and the Cr‐depleted region around the Cr‐rich phase are preferential to form pits. Therefore the G phase precipitation and the formation of Cr‐depleted region are harmful to the pitting resistance of the steel. Abstract : The microstructural characterization and pitting corrosion behavior of Z3CN20.09M duplex stainless steel were investigated by TEM, potentiodynamic polarization, and EIS after thermal aging at 475 °C for 0, 500, 1000, 2000, and 3000 h. The results showed that the ferrite in the steel decomposes into coherent Cr‐rich, Fe‐rich, and G phases. It is revealed that the pitting resistance of this steel has a negative relationship with increasing aging time.