Oxide Stability Analysis and Characterization in a Galvannealed Dual-Phase Steel Exhibiting Coating Defects
(Room 310)
06 May 19
3:00 PM
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3:30 PM
Higher levels of Mn, Si and other elements more reactive than Fe produce thicker, more adherent oxides that are difficult to remove during post-processing. Oxide prediction is of utmost importance for enabling defect-free Zn coatings. Wagner’s theory of oxidation was employed to predict the oxidation mechanism for different temperatures, furnace atmospheres and microstructures. It was shown that ferrite has an increased propensity for external oxidation, resulting in a potential increase in coating defects. Thermo-Calc® analysis showed the stable oxide phase for industrially relevant dewpoints as corundum. Different Cr-Mo levels did not affect the stable oxide phase present.