DOI: 10.5176/2251-189X_SEES19.65
Authors: Suman Bhasker Ranganath , Collin D. Wick1, and B. Ramu Ramachandran
Abstract: The early stages of oxidation of stainless steel is studied using first principles density functional theory calculations. A Monte Carlo approach was used to efficiently identify the most probable low energy structures in the high-dimensional configuration space. The composition, structure, and oxidation states of the atoms in the oxide layers were analyzed by atomic density profiles, nearest neighbor distribution, and Bader charge analysis. The results suggest that the passivation of steel by chromium is largely due to its high preference for the Cr3+ oxidation state and a structure with 6 oxygen neighbors while the iron at the surface is more susceptible to oxidation and oxygen penetration because of its relative lack of preference between a range of nearest neighbors and between the Fe2+ and Fe3+ oxidation states.
Keywords: density functional theory, stainless steel, oxidation of steel, metal passivation
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