The breakaway oxidation behaviour of ferritic stainless steels 430, 443 and 445 has been investigatedat 1150◦C in humid air. The oxidation kinetics exhibited significant differences among the three ferriticstainless steels. A uniform and steady growing oxide scale was developed on the 430 steel with an evensteel/oxide interface. Local breakdown of the initially protective oxide scale occurred and oxide noduleswere developed on the 443 and 445 stainless steels, resulting in irregular and rough steel/oxide inter-faces. The breakaway oxidation behaviour was significantly influenced by the microstructure and thecomposition of the oxide scale. The Mn-Cr spinel oxide formed on top of the Cr2O3scale in Mo alloying445 steel can greatly minimise the Cr depletion.
Cheng, X., Jiang, Z., Monaghan, B. J., Wei, D., Longbottom, R. J., Zhao, J., Peng, J., Luo, M., Ma, L., Luo, S. & Jiang, L. (2016). Breakaway oxidation behaviour of ferritic stainless steels at 1150 °C in humid air. Corrosion Science, 108 11-22.