The Promise of Mg-Li Based Alloys for Biomedical Implant Materials

Abstract

Lithium is an attractive element for Mg alloys for several reasons. It can improve room temperature ductility by transforming the single-phase hcp microstructure of Mg to a duplex phase followed by a single-phase bcc structure. With a solubility of ~5 wt.% Li, α-Mg is less prone to localized corrosion due to the absence of intermetallics. Furthermore, the strength of Mg-Li based alloys can be enhanced by alloying and thermomechanical processing. However, grain refinement has proven to be an effective mechanism in offsetting a compromise in ductility. It is for these reasons that Mg-Li based alloys have been the focus of great interest as a biomaterial where high strength, appreciable ductility and uniform corrosion behavior are required.