New insight to the oxidation kinetics of silicon-containing steel at high temperature

Abstract

This study investigated the oxidation kinetics of silicon-containing steel at 1150–1300 °C using a Simultaneous Thermal Analyzer under atmospheric conditions similar to that of an industry reheating furnace. There is a critical time point for the oxidation kinetics at an oxygen concentration of 4·0 vol.-%., following which the oxidation rate constant increases with the increasing oxidation temperature. The model coefficient A in the kinetic oxidation equation was found to be constant. However, before the critical time point, the oxidation rate constant remained unchanged; the model coefficient A decreased with the increasing temperature. Therefore, the kinetic model of silicon-containing steel for isothermal oxidation was observed to be a modified one on the basis of the experimental data. In addition, the critical time point was prolonged with the increasing isothermal oxidation temperature. Moreover, the oxidation activation energy of the tested silicon-containing steel was 366·16 kJ mol⁻¹.

Keywords:

• Oxidation kinetics
• critical time point
• oxidation temperature
• model coefficient
• oxidation activation energy
• high temperature

Acknowledgements

The authors gratefully acknowledge the financial supports from National Natural Science Foundation of China (NSFC) (No. 51274154), National Nature Science Foundation of China (No.51704217), the State Key Laboratory of Development and Application Technology of Automotive Steels (Baosteel Group).