Oxidation and surface segregation of chromium in Fe-Cr alloys studied by Mössbauer and X-ray photoelectron spectroscopy

The room temperature 57Fe Mössbauer and XPS spectra were measured for polycrystalline iron-based Fe-Cr alloys. The spectra were collected using three techniques: the transmission Mössbauer spectroscopy (TMS), the conversion electron Mössbauer spectroscopy (CEMS) and the X-ray photoelectron spectroscopy (XPS). The combination of these experimental techniques allows to determine changes in Cr concentration and the presence of oxygen in bulk, in the 300 nm pre-surface layer and on the surface of the studied alloys.