Local and electronic structure of tribological materials: XANES analysis

Tribological materials from the wheel and the wheel chock of a railway train were studied. The samples were taken from new and used wheels and wheel chock. Experimental x-ray absorption near edge spectra (XANES) spectra above the Fe L2,3 edges show the variations in the shape of the Fe L 2,3 edge fine structure, that correspond to the formation of Fe oxidized layer during the process of dry friction. Elemental analysis shows the large variations of element's distribution along the surface within 10 nm depth of damaged sample.