title: Nanoscale analysis of surface oxides on ZnMgAl hot-dip-coated steel sheets.
abstract: In this work, the first few nanometres of the surface of ZnMgAl hot-dip-galvanised steel sheets were analysed by scanning Auger electron spectroscopy, angle-resolved X-ray photoelectron spectroscopy and atomic force microscopy. Although the ZnMgAl coating itself is exhibiting a complex micro-structure composed of several different phases, it is shown that the topmost surface is covered by a smooth, homogeneous oxide layer consisting of a mixture of magnesium oxide and aluminium oxide, exhibiting a higher amount of magnesium than aluminium and a total film thickness of 4.5 to 5 nm. Especially by the combined analytical approach of surface-sensitive methods, it is directly demonstrated for the first time that within surface imprints--created by industrial skin rolling of the steel sheet which ensures a smooth surface appearance as well as reduced yield-point phenomenon--the original, smooth oxide layer is partly removed and that a layer of native oxides, exactly corresponding to the chemical structure of the underlying metal phases, is formed.
authors.affiliation: Zentrum für Oberflächen- und Nanoanalytik (ZONA) und Christian Doppler Labor für mikroskopische und spektroskopische Materialcharakterisierung (CDL-MS-MACH), Johannes Kepler Universität Linz, Altenbergerstraße 69, 4040, Linz, Austria. martin.arndt@jku.at
authors.forename: M
authors.initials: M
authors.lastname: Arndt
authors.forename: J
authors.initials: J
authors.lastname: Duchoslav
authors.forename: H
authors.initials: H
authors.lastname: Itani
authors.forename: G
authors.initials: G
authors.lastname: Hesser
authors.forename: C K
authors.initials: CK
authors.lastname: Riener
authors.forename: G
authors.initials: G
authors.lastname: Angeli
authors.forename: K
authors.initials: K
authors.lastname: Preis
authors.forename: D
authors.initials: D
authors.lastname: Stifter
authors.forename: K
authors.initials: K
authors.lastname: Hingerl