Compared with lightweight Al and Ti alloys, Mg alloys have relatively low strength and plasticity due to limited basal plane slipping systems, and strengthening Mg alloy via deformation is full of challenges. Up to now, preparing strong and ductile Mg alloys is still a difficult problem. In this work, through warm rotary swage, we successfully prepared AZ80 Mg alloys with both high strength and high ductility. Specifically, when swaged at room temperature, some macro cracks appeared, causing catastrophic failure of the swaged rods. However, the AZ80 Mg alloy rod can be swaged up to a big equivalent deformation strain at warm and exhibits both strong and ductile behavior. Microstructural characterization revealed (i) numerous <c + a> and <c> non-basal slipping systems during the warm swaging which enhances the limited plasticity of Mg alloys, (ii) a tri-modal microstructure with micro-grains surrounded by ultrafine grains network and high-density nano-precipitates, which results in both high strength and ductility, (iii) free of macro-crack etc. artifacts which avoids pre-mature failure during tension. Our work explores an effective, simple and low-cost method to prepare both strong and ductile Mg alloys for large-scale industrial applications.

Mg alloys,Nano-precipitates,Strength and ductility,Microstructure,Rotary swage