Degradation of ferritic stainless steels at 1200 °C in air

Authors

Xiawei Cheng, University of WollongongFollow
Zhengyi Jiang, University of WollongongFollow
Brian J. Monaghan, University of WollongongFollow
Raymond Longbottom, University of WollongongFollow
Dongbin Wei, University of WollongongFollow
Ay Ching Hee, University of WollongongFollow
Laizhu Jiang, Baoshan Iron and SteelFollow

RIS ID

118630

Publication Details

Cheng, X. W., Jiang, Z. Y., Monaghan, B. J., Longbottom, R. J., Wei, D. B., Hee, A. C. & Jiang, L. Z. (2018). Degradation of ferritic stainless steels at 1200 °C in air. Materials and Corrosion, 69 (1), 63-75.

Abstract

Three commercial ferritic stainless steels were investigated at 1200 °C by a thermogravimetric analyser (TGA) in air. The oxidation kinetics of the ferritic stainless steels differed significantly. The adhesion of the Cr₂O₃ scale, the morphology of the SiO₂, with or without (Cr, Mn)₃O₄ spinel on the top can greatly influence the oxidation and the degradation behaviour of the steels. Although the SUS430 steel had less Cr among the ferritic stainless steels (16.2 wt% Cr), it did not show more degradation behaviour than the B443NT steel (21.0 wt% Cr). The spallation of the protective oxide scale on the B443NT steel was caused by vacancy condensation at the scale/substrate interface where the SiO₂ particles were and the developed compressive stresses within the oxide scale during oxidation. (Cr, Mn)₃O₄ spinel on the top of the Cr₂O₃ scale on the B445J1M steel influenced its evaporation rate. The thermodynamic aspect of the chemical composition and oxidation atmosphere of the Fe–Cr–O system was also discussed.