Study of Corrosion Behavior of Hard Anodized Magnesium Alloy by Dow-17 Process

This study focuses on enhancing the corrosion resistance of AZ91D magnesium alloy, known for its impressive strength-to-weight ratio within the magnesium group. Despite its lightweight properties, the alloy's moderate corrosion and wear resistance have restricted its widespread use. To address this limitation, we explored the application of the Dow 17 process to enable hard anodizing of AZ91D magnesium alloy. Our primary objective is to investigate the impact of hard anodizing on AZ91D magnesium alloy and its potential to mitigate corrosion issues. Hard anodizing results in the formation of a robust oxide film on the alloy's surface. We posit that this oxide film can significantly reduce substrate corrosion, expanding the alloy's utility in various applications. To substantiate our claims, we conducted a comprehensive corrosion performance analysis of AZ91D magnesium alloy, with and without hard anodizing treatment. We employed advanced techniques, including potential dynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS), to compare the corrosion behavior of treated and untreated specimens. Preliminary results suggest that the presence of a thick oxide layer resulting from hard anodizing greatly improves corrosion resistance properties. This promising outcome underscores the potential of hard anodizing as a method to enhance the corrosion resistance of AZ91D magnesium alloy, opening new possibilities for its application in diverse industrial applications. The key parameters of this research work are Coating Thickness, Anodizing Duration, Hard Anodizing Process and Surface Preparations.