Surface Oxidation and Wettability of Fe–Mn and Fe–Mn–Si-Alloyed Steel After Annealing

Journal article (2022)

Authors

Y. You Team Kevin Rossi - Mechanical, Maritime and Materials Engineering
C. Kwakernaak Team Maria Santofimia Navarro - Mechanical, Maritime and Materials Engineering
J.C. Brouwer Team Marcel Hermans - Mechanical, Maritime and Materials Engineering
Ruud Westerwaal Tata Steel
W.G. Sloof Team Kevin Rossi - Mechanical, Maritime and Materials Engineering
Research Group
Team Kevin Rossi (Mechanical, Maritime and Materials Engineering) (TU Delft)
Copyright: © 2022 Y. You, Jungki Kim, C. Kwakernaak, J.C. Brouwer, Ruud Westerwaal, W.G. Sloof
DOI: https://doi.org/10.1007/s11661-022-06847-3
More Info
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Published Date

2022

Language

English

Faculty

Mechanical, Maritime and Materials Engineering

Department

Materials Science and Engineering

Research Group

Team Kevin Rossi

Abstract

The surface oxidation and wettability of Mn and Si-alloyed steel after annealing at different conditions are studied with scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and a so-called de-wetting method. After exposure at 950 °C for 1 hour in an Ar + 5 vol pct H2 gas atmosphere with dew points (DP) ranging from – 40 °C to 10 °C, oxides were observed along the grain boundaries or dispersed on the surface for the Fe–1.8 Mn steels while a continuous oxides layer was formed on Fe–1.9 Mn–0.94 Si steels (composition in weight fractions). The oxides formed at different DPs were predicted based on thermodynamic calculations. (Fe,Mn)O was formed on Fe–1.8 Mn steel at the whole range of DPs, while the oxide phase on Fe–1.9 Mn–0.94 Si steel depends on the DP. At low-DP SiO2 were formed and with increasing the DP (Fe,Mn)SiO3 or (Fe,Mn)SiO3 + (Fe,Mn)2SiO4 were formed and finally (Fe,Mn)2SiO4 were formed. An increase of the fraction of Fe in the oxide with increasing DP for both steels was observed with XPS analysis. As a measure for the surface wettability, the contact angle of Pb droplets on the annealed steels surfaces was determined with SEM and image analysis software. Also, the contact angle of Pb on pure Fe and on the Mn and Si alloyed steels free of surface oxides was measured for comparison. The results show that the contact angle of Pb on the steel surfaces after annealing decreases with increasing DP. This improved wettability with increasing dew point is related to the Fe fraction of the oxides formed on the surface.