Research Progress and Application Prospect of Directionally Solidified Mg Alloys

Mg and its alloys show great advantages in lightweight, energy saving and emission reduction for their low density and high specific strength, and attract increasing attention in automobile, electronics, aerospace and other fields. However, the problems such as low strength, poor deformability, high chemical activity and poor corrosion resistance still limit the widespread applications of Mg and its alloys. Thus, the development of Mg alloys with high-performance is still the focus of recent studies. Various methods have been explored to improve the mechanical properties and deformability of Mg alloys, such as alloying, heat treatment and development of new Mg-based composites, but few researches are focused on the relationship between the solidification characteristics and the properties of Mg alloys. Exploration into the solidification characteristic and control of solidification path not only have scientific significance but also can provide a theoretical basis for alloy design and fabrication. Both are beneficial to the extensive application of Mg alloys. Designed microstructure can be obtained by directional solidification technology through adjusting the solidification parameters, which makes it convenient to obtain the relationships among composition, microstructure, processing parameter and performance. In recent years, lots of experimental and theoretical studies have been carried out and shed light on the knowledge of microstructural evolution, growth orientation and mechanical properties of directionally solidified Mg alloys. In this work, the development of directionally solidified Mg alloys, including the newest research progress and the existing problems are summarized, and their potential application is prospected. © 2022, Materials Review Magazine. All right reserved.