Effect of Mn and Ca on mechanical, corrosion and surface roughness of Mg-5Sn alloy

Magnesium and its alloys have an extensive application prospect in the aerospace, automotive industry, sports equipment, biomedical and energy storage due to their high specific strength and low density compared with iron and Aluminum alloys. However, the strength and the corrosion resistance of Mg alloys is still the major drawback that hampers their application. Alloying is generally used to improve mechanical and corrosion properties. The mg-Sn alloy system was extensively studied and the Mg-5Sn alloy was chosen as the base composition owing to the addition of 5 wt% Sn improves the strength and corrosion resistance of pure Mg. The present work aims to investigate the effect of Mn and Ca addition on mechanical, corrosion and roughness properties of as-cast Mg-5Sn-Mn-Ca alloy. The addition of Mn and Ca elements significantly refined α-Mg grains. Mn-rich phase precipitated alongside intermetallic eutectic Mg2Sn phases and CaMgSn eutectics observed on the grain boundaries. The strength, hardness, roughness, and corrosion resistance of Mg-5Sn alloy are observed to be improved by the addition of Mn and Ca.