Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1470025 | Corrosion Science | 2011 | 10 Pages |
Characteristics of oxide films formed on 304 stainless steel under alternately changing Ni2+ concentrations in oxygenated high temperature water were examined. Oxides preformed under low Ni2+ concentration evolve from hematite to spinel after subsequent immersion under high Ni2+ concentration. Meanwhile, Ni content in the surface layer of oxide rises up while Fe content drops. Oxide films preformed under high Ni2+ concentration show little change in phase composition after subsequent immersion under low Ni2+ concentration. Fe contents in surface layer rise up while the change of Ni contents depends on the original phase composition and whether residual Ni2+ is present.
► Hematite preformed under low Ni2+ level evolves into spinel under high Ni2+ level. ► Oxide films maintain in phase composition when Ni2+ level changes from high to low. ► Oxide film preformed under high Ni2+ level could consume trace Ni2+ in solution.