Effect of Oxidation Temperature on the Oxidation Process of Silicon-Containing Steel

The oxidation behavior of silicon-containing steel was studied by applying segmented heating routes similar to the atmosphere and heating process in an industrial reheating furnace. The oxidation tests were carried out on a simultaneous thermal analyzer at heating temperatures of 1150 ̋C–1300 ̋C. The morphologies of Fe2SiO4 were observed by SEM, and the penetration depths of the Fe2SiO4 layer at different oxidation temperatures were determined by using the Image-Pro Plus 6.0 software. The results show that at heating temperatures ě1235 ̋C, the oxidation rate and total oxidation mass gain have no relation with the heating temperature; the mass gain versus time follows a linear law after about 1164 ̋C (lower than the eutectic temperature of fayalite). In addition, the oxidation rate first decreases slowly and then drops from 1190 ̋C to 1210 ̋C during the isothermal holding stage. With the increase in temperature, the oxidation rate and mass gain also increase gradually; the relationship between the mass gain and time is close to a parabolic law. Moreover, at a heating temperature of 1150 ̋C, the oxidation rate decreases rapidly during the isothermal holding stage, and the mass gain versus time follows a parabolic law.