Sustainable magnesium recycling: Insights into grain refinement through plastic deformation-assisted solid-state recycling (SSR)

Magnesium, the lightest structural metal, is increasingly adopted in various industries, particularly automotive and aerospace, underscores the economic importance of magnesium due to its high specific strength, stiffness, and excellent damping properties. However, the primary production of magnesium is highly energy-intensive and environmentally challenging. Solid-state recycling via plastic deformation techniques offers a promising alternative to manufacturing ultrafine-grained magnesium samples with superior characteristics. Given the lack of reviews on the mechanisms of grain refinement during the solid-state recycling of magnesium and its alloys, this paper addresses this gap by offering detailed insights. Through an extensive review of relevant literature, the current paper highlights how plastic deformation techniques facilitate grain refinement during the solid-state recycling of magnesium chips and wastes. In this regard, a grain refinement mechanism during SSR of Mg and its alloys is proposed by the authors, to guide future advancements in sustainable magnesium recycling technologies. This will clarify the benefits of solid-state recycling over traditional methods, such as higher metal yields and better mechanical properties.