Effect of Sr on Mechanical Properties and Corrosion Behavior of Rolled ZM60 Alloy

Mg-6Zn-0.5Mn as a medical magnesium alloy has good biomechanical properties and corrosion resistance, but as a fracture internal-fixation material, its strength, toughness, and corrosion resistance still need to be improved. In this paper, the element Sr, having good biocompatibility, is used as an alloy element. The effects of different Sr contents (0 wt.%, 0.3 wt.%, 0.6 wt.%, 0.9 wt.%, and 1.2 wt.%) on the microstructure, strength, toughness, and corrosion resistance of rolled Mg-6Zn-0.5Mn alloy were studied. The results are as follows. Sr can influence the recrystallization process. When the Sr content is 0.3 wt.% and 0.6 wt.%, the alloy matrix exhibits both non-recrystallized regions and fine recrystallized regions. When the Sr content reaches 0.9 wt.%, the non-recrystallized region decreases significantly, and the fine recrystallized grains develop into equiaxed grains. With the increase of Sr content, the elongation of the alloy decreases. At a content of 0.9 wt.%, the corrosion resistance reaches its optimum value, with an average corrosion rate of 0.75828 mm/y.