Investigation of Biodegradable Zn–Li–Cu Alloys for Orthopaedic and Cardiovascular Applications

Abstract

The ternary Zn–Li–Cu alloy system is investigated as a potential biodegradable metal for orthopaedic and cardiovascular applications. The phase composition, microstructure, hardness, and in vitro corrosion rate of hot-rolled Zn, Zn–0.3Li, Zn–0.3Li–3.5Cu, and Zn–0.3Li–5Cu are examined. The addition of Li and Cu produce LiZn4 and CuZn5 binary phases within the Zn matrix, while there is no interaction between Li and Cu. Hot rolling induces grain refinement and a rolling texture with the addition of Li and Cu. The hardness substantially increases from 39.16 ± 1.49 Hv (pure Zn) to 133.85 ± 4.38 Hv (Zn–0.3Li–5Cu). Immersion-based corrosion rate in Hanks’ solution increases with small additions of Li and Cu content due to microgalvanic behavior. Large addition of Cu promotes a lower corrosion rate due to the noble contribution of CuZn5 phase. The outcome of this study promotes further analysis of the Zn–Li–Cu ternary system for biodegradable metal applications.