Magnesium alloys, the lightest metallic structural material in practical applications, are gradually becoming an ideal choice for various fields such as aerospace, transportation, defense, equipment manufacturing, and 3C electronics due to their superior performance. Their high specific strength, high specific stiffness, excellent elastic modulus, as well as good biocompatibility, thermal and electrical conductivity, electromagnetic shielding capabilities, and damping performance, have led to magnesium alloys being hailed as "the most promising green engineering material of the 21st century."

Rolling technology, as a key technology in the production of magnesium alloy sheets, has significant advantages. It can flexibly produce sheets of different thicknesses and widths to meet diverse needs. At the same time, rolling is also the most economical and efficient method for preparing magnesium alloy sheets through plastic forming. Through this process, grains can be refined, the microstructure optimized, and the mechanical properties of the alloy significantly improved. However, despite the important role of rolling technology in the production of magnesium alloy sheets, it still faces some challenges. For example, rolled sheets often exhibit high anisotropy, poor stamping formability, prominent edge cracking problems, and low material utilization. These problems, to some extent, limit the further application of magnesium alloy sheets.
 

Conventional Rolling Technology
 

> Traditional Rolling Processes

Traditional rolling processes mainly involve hot rolling and warm rolling of magnesium alloy ingots on a rolling mill, sometimes with cold rolling in the final stage, to produce magnesium alloy sheets. This process can effectively refine the grain structure of magnesium alloys, thereby improving their mechanical properties to some extent. However, it also has some drawbacks. Because traditional rolling uses a multi-pass, small-deformation rolling method, intermediate steps such as annealing and heating the rolls are required, which not only reduces production efficiency but also wastes resources, resulting in high production costs for magnesium alloy sheets.

> Hot Extrusion Rolling

Hot extrusion rolling, as a common rolling process, shapes magnesium alloy sheets into the desired shape through hot extrusion. The extrusion process within the extrusion cylinder allows for slow heat dissipation, fully utilizing the plasticity and helping to reduce the formation of cracks in the magnesium alloy. This makes this method the preferred choice for the production of most magnesium alloy sheets. However, it also has some drawbacks, such as limitations on the size of the rolled sheets, material waste, low yield, and high investment in equipment and instruments.

Twin-roll continuous casting (TRC) is another method for preparing magnesium alloy slabs. This technology uses two counter-rotating rolls as crystallizers. After the magnesium alloy feedstock is melted, the melt is uniformly introduced into the gap between the rolls through a distribution system (casting nozzle). In this process, casting and plastic forming are combined; the magnesium alloy solution undergoes plastic deformation while rapidly cooling, thus efficiently producing magnesium alloy slabs of the desired shape. However, TRC also presents some challenges, such as high requirements for equipment precision and process control, and potential issues related to magnesium alloy composition and temperature control.