Oxide Scale Growth on High Carbon Steel at High Temperatures

The structure and formation process of oxidation on high carbon steel were investigated with the aid of X-ray diffraction （XRD）, scanning electron microscope （SEM） and Laser Raman spectroscopy （LRS）. The oxide scale formed comprised a three-layer structure, similar to that formed on pure iron and low-carbon steel. For the high carbon steel, however, the scale was essentially a two-layered because of the low proportion of hematite （Fe2O3） formed. The scale thickness increased with the temperature and time of oxidation. The rate of scale thickening rapidly increased above 900 ℃, at which the rate was particularly fast in the first 20 s of oxidation. The proportion of wüstite （Fe1-yO） increased with time and temperature of oxidation, while the magnetite （Fe3O4） remained constant at about 2 μm.