Distribution Around the Oxide-Substrate Interface of Alloying Elements in Low-Carbon Steel

In order to study the physicochemical evolutionduring oxidation of Fe-C-X_i alloyssurfaces (X_i = Cu, Ni, Al, Si, S, withX_i% < 0.5 wt.%, C% < 0.1 wt.%), anoriginal analysis method has been used. After separating the oxide from the metalsubstrate, the first atomic layers of both innersurfaces have been observed by Auger ElectronSpectroscopy (AES). The depth profiles obtained, around0.4 m thick on both sides of the oxide-metal interface,have been compared for four steels of differentcomposition. Significant differences have been observedand described in this paper. A qualitativeinterpretation of diffusion processes has been proposed. Ametallographic study illustrates some physicalconsequences of alloying elements, especially on thescale thickness.