The role of rare earth elements in the development of magnesium base alloys

This paper examines the importance of rare earth metals in the development of magnesium alloys, and their effect on mechanical properties and corrosion resistance. Examples are given of commercial and some experimental alloys, and their advantages and limitations are briefly discussed. A number of alloy compositions that are suitable for the production of shapes using sand, gravity die and precision (e.g. lost–wax) casting techniques, and offering a range of properties, are in commercial use and new alloys are being introduced. No alloy has yet been developed which is suitable for high–pressure die casting. Although a number of alloy compositions offer attractive properties in the wrought condition, little commercial use has been made of them. Rare earth elements are being studied in connection with rapid solidification techniques and a number of compositions offering high ambient–temperature strength and excellent corrosion resistance have been reported. Finally, opportunities for further research and de...