Effect of epoxy resin/mineralized film composite coating on the corrosion resistance of Mg-3Nd alloy

Abstract

Adding an anti-corrosion coating to the surface of magnesium (Mg) alloy is an effective means to improve its corrosion resistance, but it is particularly important to enhance the bonding force between the anti-corrosion coating and the Mg matrix. Epoxy resin coating is considered the most cost-effective approach from an industrial standpoint, while the hindering the wider utilization of Mg alloys with epoxy coating in the realm of engineering materials are due to their insufficient adhesion between Mg matrix and the epoxy coating. Here, we demonstrated a simple method for forming an epoxy resin/mineralized film composite coating. The mineralized products coatings were applied to the surface of Mg-3Nd alloy, via a direct reaction between Mg and 15 wt% Na2CO3 solution. Due to the inherent lamellar structure of alkaline magnesium carbonate mineralization film, the mechanical interlocking between the epoxy resin and the Mg substrate are remarkably strengthened. Therefore, this simple surface treatment method is promising to improve the adhesion between the epoxy resin and the matrix. Moreover, the effects of mineralized products coating on the corrosion resistance of Mg with epoxy coating were researched. It was observed that the corrosion resistance of Mg alloy with composite coatings are significantly enhanced. Such an investigation aims to provide a new method for developing a cost-effective and robust epoxy resin/mineralized film composite coating protection structure of Mg alloys in practical applications.

Keywords

• Epoxy resin
• Mineralization treatment
• Composite coating
• Adhesion
• Corrosion product