Effect of solid solution treatment on biomedical Mg-Li alloy with high Zn content

Microstructure, mechanical strength, corrosion resistance, and osteogenesis of as-cast Mg-11 wt% Li-12 wt% Zn alloy were investigated before and after solid solution treatment. Massive MgLiZn and MgLi2Zn phases were formed in the as-cast sample, resulting in micro-galvanic corrosion and high corrosion rate. After the solid solution treatment, the lath-shaped α-Mg phase remained in the β-Li matrix, whereas the large MgLiZn and MgLi2Zn phases dissolved in it, resulting in enhanced the corrosion resistance. Moreover, the yielding strength of the as-cast sample was improved from 136 to 260 MPa after treatment. In addition, the solid solution-treated Mg-Li-Zn exhibited improved induction of the alkaline phosphatase activity and osteogenesis-related gene expression in rBSMCs, confirming its promising potential for orthopedic applications.