Abstract
The high-temperature oxidation kinetics of Galvalume-coated steel sheet and Q235 steel sheet were studied by thermogravimetric analysis (TGA). A new diffusion equation was deduced and used to investigate their kinetic mechanism. The characteristic time (tc) in the equation can be expressed as a function of temperature T, diffusion coefficient D0, thickness of the steel sheet H, etc. The calculated result showed that the oxidation reaction rate of Galvalume-coated steel sheet was slower than that of Q235 steel sheet through comparing the values of tc. Besides, the oxidation reaction rate increased with the temperature rising from 750 to 850 °C. Compared our experimental data with the theoretical value calculated by the new function, a good agreement has been obtained.
Publisher
Trans Tech Publications, Ltd.