Corrosion and Electrochemical Behaviors of As-Cast Mg-8Y and Mg-5Y-7Gd-1Nd-0.5Zr Magnesium Alloys in NaCl Aqueous Solution

Abstract:

The corrosion mechanisms of as-cast Mg-8Y and Mg-5Y-7Gd-1Nd-0.5Zr Mg alloys in 5% NaCl aqueous solution were investigated by electrochemical testing and SEM observation. The electrochemical results indicated that the corrosion resistance of Mg-8Y and Mg-5Y-7Gd-1Nd-0.5Zr alloys in 5% NaCl aqueous solution gradually deteriorated with increasing of immersion time expect for 2h and 24h immersion. The Cl^- anion led to the initiation and development of the corrosion pits. The cathodic reaction was driven by hydrogen evolution reaction. The presence of filiform corrosion also proved a resistant oxide film naturally formed on the surface of Mg-8Y and Mg-5Y-7Gd-1Nd-0.5Zr alloys. The corrosion resistance of Mg-5Y-7Gd-1Nd-0.5Zr was better than Mg-8Y.

• Periodical: Materials Science Forum (Volumes 747-748)
• Pages: 437-442
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.747-748.437
• Online since: February 2013
• Authors: Xin Zhang, Xia Deng, Kui Zhang, Xing Gang Li, Yang Shi, Yu Long Zhang, Min Peng, Ling Ying Kong
• Keywords: Corrosion Behavior, Electrochemical, Mg-5Y-7Gd-1Nd-0.5Zr, Mg-8Y

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