Corrosion and Surface Studies of Stainless Steel and Chromium Carbide Thin-Films
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Although the passive films that form on stainless steels have been extensively studied, the concentration depth profiles are not fully understood. Their thinness makes passive films hard to study, but angle-resolved X-ray photoelectron spectroscopy (ARXPS) is a non-destructive technique that can be used to obtain depth information. An iterative approach to deconvolute ARXPS measurements into depth profiles is discussed, and the chemistry of passive films on a molybdenum-containing 316L stainless steel is investigated. Bipolar electrochemistry, in which the sample is placed along an electric field created by two driving electrodes in an electrolyte, is investigated as a screening tool. It is shown that the method is useful to create corrosion gradients on 304 stainless steel, both under pitting and non-pitting conditions. Chromium carbide thin films were deposited by magnetron sputtering with a variety of deposition parameters on stainless steel, and subsequently analyzed. It is shown that these films present a promising material system for protective coatings to improve the corrosion resistance of stainless steels while also maintaining other useful properties, such as low interfacial contact resistance. Particular attention is given to the electrochemical evaluation of the films, whose high carbon concentrations necessitates different interpretations of the electrochemical results compared to for stainless steels.
Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2013. , 66 p.
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1082
corrosion, electrochemistry, thin film, stainless steel, passive film, chromium carbide, carbon oxidation, surface, depth profile, XPS, SEM, EQCM, sputtering
IdentifiersURN: urn:nbn:se:uu:diva-208410ISBN: 978-91-554-8766-9OAI: oai:DiVA.org:uu-208410DiVA: diva2:652266
2013-11-08, Ångström 2001, Lägerhyddsvägen 1, Uppsala, 10:15 (English)
Nyholm, LeifEdström, Kristina
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