Semisolid rheoforming of magnesium alloys: A review

A reflection upon the recent developments of semisolid rheoforming techniques of magnesium (Mg) alloys is vital for successfully shaping the future landscape of lightweight and high-performance metal materials. In our paper, formation mechanisms of non-dendritic structure were firstly reviewed, and slurry preparation methods as well as rheoforming processes of Mg alloys were then summarized. Afterwards, microstructures and mechanical properties of semisolid Mg alloys were elaborated. The various formation mechanisms of non-dendritic structures provide theoretical bases for understanding the microstructure evolution of semisolid metal slurries. Despite the abundant slurry preparation methods to date, inexpensive industrial solutions for producing high-quality Mg alloy slurries are still scarce, which is constituting one of many key challenges in the future. In the case of rheoforming processes, high pressure die casting (HPDC) and squeeze casting are the most promising processes for mass production of semisolid Mg alloys. At present, researches on semisolid Mg alloys are mainly focused on AZ and AM series alloys. To develop high-performance semisolid Mg alloys, the slurry preparation and rheoforming technology of Mg-RE alloys are worthy of further investigation.