Micro-analysis on Oxide Scale of U75 V Hot Rolled Rail

The surface morphology,section morphology,thickness and microstructure of oxide scale on the surface of U75 V hot rolled rail were observed by optical microscope,scanning electron microscope and energy spectrum.The causes for the difference of thickness and morphology of oxide scale on rail and strip surface were analyzed.The study shows that the scale has a typical three layer structure of FeO,Fe₃O₄ and Fe₂O₃ oxides from inside to outside,the concentration of Si elements exists at the interface between the inner layer and the matrix.The average thickness of oxide scale of rail is over 50 μm,the thickness of underside is bigger than upside.The difference of thickness and morphology of oxide scale on rail and strip surface is mainly related to the section shape and the production process.