Elucidating the passivation kinetics and surface film chemistry of 254SMO stainless steel for chimney construction in simulated desulfurized flue gas condensates. (24th May 2021)

• Record Type: Journal Article
• Authors: Ge, Feng; Wang, Liwei; Dou, Yunpeng; Wei, Junyang; Cheng, Lianjun; Wang, Xin; Cui, Zhongyu
• Is Part Of: Construction & building materials. Volume 285(2021)
• Publication Date: 2021-05-24
• Subjects: Stainless steel -- Desulfurized flue gas condensates -- Acid corrosion -- Passivation; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2021.122905
• Languages: English
• ISSNs: 0950-0618

Abstract

Graphical abstract: Highlights: The film electric field strength and donor density increase at high temperatures. Anodic potential rather than temperature increases the point defect diffusivity. A higher fraction of oxidized Cr and Fe(II) formed at high temperatures. Lower donor density but higher electric field strength within the anodic film. Higher Fe(II)/Fe(III) and Crox+hy /Feox+hy ratios in anodic film than at OCP. Abstract: Temperature-dependent passivation kinetics and surface film chemistry of 254SMO stainless steel in the simulated desulfurized flue gas condensates in thermal power plant chimney are investigated. Increasing temperature increases the electric field strength and multiplies the donor density, but exhibits little effect on point defect diffusivity within the passive film. The mixed Cr III -Fe II/III -Mo IV/VI oxide/hydroxide film with a higher amount of oxidized Cr and Fe II compounds is formed at high temperatures. Anodic polarization generates a less oxidized film with higher Fe II /Fe III and Cr ox + hy /Fe ox + hy ratios as compared to that formed at OCP when the film thickness is indistinguishable between the two film formation approaches. This steels provides an acceptable resistance to the attack of the flue gas in the chimney of thermal power plat.