Phase identification of oxide scale on low carbon steel

The classical model of iron oxide scale layers; wüstite, magnetite and hematite, is more complicated in reality and its properties change with the factors that affect their development, such as time, temperature, alloying elements in the steel and oxidation environment. An understanding of the oxide scale formation and its properties can only be achieved by careful examination of the scale microstructure. Throughout this study, electron back-scatter diffraction (EBSD) has proved to be a powerful technique for verifying the individual phases in the oxide scale accurately. The results show that EBSD can be used to give a complete characterisation of the oxide scale formed on low carbon steel surface. Microstructural features such as grain size, shape and grain boundary characteristics have been successfully determined and analysed.