Magnesium alloys are metallic materials that are finding increasing use in automobile and other industries. In particular, due to their intrinsic lightweight characteristics, their use as structural components can significantly improve energy consumption efficiency. However, their overall properties need to be improved in order to be able to use their unique advantages and to replace components made of conventional aluminum alloys and steels with Mg alloys. In this work, the current status of research and development in new Mg alloy design for solidification technology is surveyed with a focus on alloying with rare earth elements (RE). Reports and patents from the recent decades on newly developed magnesium alloys exhibiting high performance are compiled and described. Mg - Al - RE, Mg - Al - Ca - RE, Mg - Al - Zn - RE, Mg - Y - Gd, Mg - RE - Zn - based alloys and Mg alloys with no RE addition are described. Previous studies on strategic new alloy designs using equilibrium phase diagrams are discussed. Lastly, a brief comparative study of these alloys as well as issues for future development are discussed.
Keywords: Magnesium alloy, new alloy design, alloying, equilibrium phase diagram, rare earth elements, solidification, microstructure, mechanical properties