Anodizing treatments for magnesium alloys and their effect on corrosion resistance in vaious environments

Abstract

This paper reviews various aspects of anodizing of magnesium alloys, such as the basics, processes, properties and applications. It systematically summarises the existing fundamental studies and technical developments of anodizing of magnesium alloys, and concludes that new anodizing processes based on electrolytic plasma anodizing that convert the surface of a magnesium alloy into a hard ceramic coating in an electrolytic bath using high energy electric discharges can offer improved wear and corrosion resistance. These newanodized coatings are often claimed to performbetter than the traditional ones obtained through older anodizing processes, such as DOW17 or HAE. The new anodizing techniques are chromate free and hence environment friendly. It is expected thatmore cost-effective, environment-friendly and non-toxic anodizing techniques will be developed and applied to magnesiumalloy components in the future.