The Production of Rare Earth based Magnesium and Aluminium Alloys – A Review

Rare Earth (RE) elements can be used as alloying agents to improve properties such as strength, conductivity, and corrosion resistance of Al or Mg light metal (LM) alloys. The current route for producing Al/Mg-RE alloys is by melting Al or Mg with the required RE metal. However, the high price of RE metals makes the cost of the alloys expensive and, as a result limits, their application. Extensive studies have been conducted to find alternative process routes to making RE alloys with the aim of making the alloys more efficient and less costly. In this study, a comprehensive overview of alternative Al/Mg-RE alloy production methods is provided. Three alternative routes are identified and reviewed: the direct metallothermic reaction of the metal with RE compounds; a multistage reduction of RE compounds; and the electrolysis route. Recommendations for ongoing and future research into Al/Mg-RE alloys as well as industrial implications are also discussed.