Alloying design strategy for biodegradable zinc alloys based on first-principles study of solid solution strengthening

Abstract

The solid solution strengthening of Li, Mg, Al, Mn, Cu and Ag in biodegradable Zn-based alloys is quantitatively investigated by first-principles calculations based on density functional theory. The alloying effect on lattice parameters and elastic constants is determined. Mn is found to have the greatest impact on the lattice parameters and shear modulus, while Mg and Al exhibit the least. According to the theories proposed by Fleischer and Labusch, the strengthening capability of selected elements can be ranked as Mn > Li > Cu, Ag > Mg > Al. The different strengthening effect of solutes can be attributed to their valence electron structure. Analysis on experimental results indicates that ternary Zn-based alloys may satisfy the clinical requirements on mechanical properties with less secondary phase and suppressed mechanical instability.

Keywords

• Biodegradable Zn-based alloys
• Solid solution strengthening
• Density functional theory
• Mechanical properties