Effect of oxidation temperature on the oxidation process of silicon-containing steel

Abstract

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 ≥1235 °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.