In-situ synchrotron GIXRD study of passive film evolution on duplex stainless steel in corrosive environment


Ornek C. , Langberg M., Evertsson J., Harlow G., Linpe W., Rullik L., ...More

CORROSION SCIENCE, vol.141, pp.18-21, 2018 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 141
  • Publication Date: 2018
  • Doi Number: 10.1016/j.corsci.2018.06.040
  • Title of Journal : CORROSION SCIENCE
  • Page Numbers: pp.18-21
  • Keywords: Passivity, Oxide film, Duplex stainless steel, Grazing-incidence X-ray diffraction (GIXRD), Selective dissolution, De-alloying, MOLYBDENUM, BEHAVIOR, PHASES

Abstract

This paper presents new findings about the passive film formed on super duplex stainless steel in ambient air and corrosive environments, studied by synchrotron grazing-incidence X-ray diffraction (GIXRD). The passive film, formed in air, was seen to be a nano-crystalline mixed-oxide. Electrochemical polarisation to the passive region in aqueous 1 M NaCl at room temperature resulted in an increase of the passive film thickness, preferential dissolution of Fe, and partial loss of crystallinity. After termination of polarization to the transpassive regime, reformation of the mixed-oxides was observed, showing a thicker, semi-crystalline, and more defective nature (more vacancies) with further new oxides/hydroxides.