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

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.