Characterization and Structure Analysis of the Anodic Film Formed on AZ31 Mg Alloy in KOH Alkaline Solution with Various Additives

Abstract:

AZ31B Mg alloy was anodized under the current density of 20 mA cm-2 for 3.6 ks in KOH alkaline solutions contains 0.60 M KF, 0.09 M Na₃PO₄.12H₂O, 0.45 M Al (OH)₃ and 0.13 M KMnO₄ at 298 °C. Pores structure anodic film was formed on magnesium alloy surface; the pours structure was also observed in the lower part of the anodic film. The anodic film consisted of MgO and MgAl₂O₄. The anodized film showed higher pitting potential from anodic polarization measurement in 0.1 M NaCl solution compared to non-anodized magnesium alloy specimen and leads to improve the corrosion resistance of anodized AZ31 magnesium alloy.

• Periodical: Key Engineering Materials (Volume 786)
• Pages: 159-164
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.786.159
• Online since: October 2018
• Authors: K. Nishinaka, S.A. Salman*, K. Kuroda, M. Okido
• Keywords: Alkaline-Solution, Anodizing, Corrosion, Mg-Alloy, Surface-Treatment

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