The effects of Ca on the microstructure, mechanical and corrosion properties of extruded Mg–2Zn–0.5Mn alloy

Abstract

In this study, the microstructure, mechanical properties and corrosion behavior of as-extruded Mg–2Zn–0.5Mn–xCa (x=0, 0.2, 0.4) alloys were investigated. The results showed that alloying with Ca refined the grains of the extruded rods and increased the unrecrystallized region, which leaded to an increase in ultimate tensile strength and a decrease in elongation. With the addition of Ca, the overall texture intensity of the alloys increase, and it is found that the texture of the alloys is mainly determined by the coarse deformed grains. The corrosion experiment of the alloys in hanks balanced salt solution (HBSS) shows that the corrosion product film of the alloys becomes denser with the addition of Ca. At the same time, the addition of Ca element introduces Ca2Mg6Zn3 phase, which reduces local corrosion, the corrosion resistance is improved.

Keywords

• Mg–Zn–Mn–Ca alloy
• Ca2Mg6Zn3 phase
• Hot-extruded
• Microstructure
• Mechanical properties
• Corrosion properties