Chemical depth profile of passive oxide on stainless steel

Journal Article · Mon Dec 27 04:00:00 EST 2004 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.1842362· OSTI ID:20634585

Kim, D H; Lee, H H; Kim, S S; Kang, H C; Noh, D Y; Kim, H; Sinha, S K ^[1]

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1. Department of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)

The chemical depth profile of the passive oxides formed on a stainless-steel surface (type 430, Fe-16.3%Cr) in pH 8.4 borate solution was obtained quantitatively by in situ anomalous x-ray reflectivity. The passive film consists of a Cr oxide inner layer and a Fe/Cr oxide outer layer. The absence of Fe oxide underneath Cr oxide indicates that Cr oxide provides the passivity in stainless steel by inhibiting oxygen anion diffusion. The oxide grows by limited metallic cation transfer. The passivity breaks down in transpassive regime due to the oxidation of the Cr oxide to a soluble oxide.

• OSTI ID: 20634585
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 26 Vol. 85; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANIONS
BORATES
CATIONS
CHEMICAL ANALYSIS
DIFFUSION
LAYERS
OXIDATION
OXIDES
OXYGEN
PASSIVATION
PASSIVITY
PH VALUE
REFLECTIVITY
SOLUTIONS
STAINLESS STEELS
THIN FILMS
VOLTAMETRY
X RADIATION