Modification of Mg Alloy Surfaces Based on Micro-Arc Oxidation Methods

Abstract:

Chemically and mechanically protective coatings are formed on surface of Magnesium alloys by micro-arc oxidation (MAO) methods. Modification of the obtained MAO surfaces was made in two aspects. Firstly, the protection is enhanced by forming super-hydrophobic surfaces, with water contact angle higher than 120^o, attributed to hierarchical nanomicro structures. The overall process involves alkaline etching to form nanoscale structures on top of micro-porous surface achieved during micro-arc oxidation processes. Secondly, the electrical property of the MAO surfaces is modified. A film with electrical conductivity of 2.4Ω/sq is achieved by Ni deposition and characterized by four point probe measurement. The morphology, phase, and chemical composition of all surfaces are investigated by SEM, AFM, and XRD analysis.

• Periodical: Advanced Materials Research (Volume 905)
• Pages: 146-150
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.905.146
• Online since: April 2014
• Authors: Hong Tao*, So King Ho, Echo Li, Xue Zhu Zhang, Gary Lai
• Keywords: Corrosion Resistance, Micro-Arc Oxidation, Nanostructure, Super-Hydrophobic

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