Tailoring the microstructure and improving the discharge properties of dilute Mg-Sn-Mn-Ca alloy as anode for Mg-air battery through homogenization prior to extrusion

Mg-0.5Sn-0.5 Mn-0.5Ca (wt.%) alloys with different microstructures are designed through casting and extrusion with and without homogenization treatment prior to extrusion (HPE). The influence of HPE treatment on the microstructural characteristics and resultant discharge properties of Mg-Sn-Mn-Ca alloy in extruded condition as anode for Mg-air battery was investigated. HPE treatment exerts a prominent effect on the grain structure and orientation, distribution of the second phase particles as well as the dislocation density of the extruded alloy. The HPE alloy exhibits a distinctly high cell voltage together with specific energy compared with that of Non-HPE one. Intermittent discharge tests confirm that the HPE alloy possesses a more excellent discharge activity and more stable discharge process than the Non-HPE one. All results demonstrate that the HPE alloy is an attractive anode material for Mg-air battery with long-term storage and under intermittent discharge. (C) 2020 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.