Morphology and Mechanical, Corrosive, and Antibacterial Behaviors of Indirectly Extruded Zn-0.05wt.%Mg-(0.5, 1 wt.%)Ag Alloys

Biodegradable Zn-0.05Mg-(0.5, 1 wt.%) Ag alloy was manufactured by indirectly extruding the alloy ingot at 200 °C with an extrusion ratio of 16:1. Dynamic recrystallization took place during the extrusion process, leading to the formation of equiaxed crystals with twins in both cross-sectional and longitudinal direction. There was no detectable Ag-related phase present except the Mg 2 Zn 11 in the alloys. Tensile strength was increased with an increase in Ag content, reaching 202 MPa when Ag content is 1 wt.%. As-extruded Zn-0.05Mg-0.5Ag showed better corrosion performance with a low corrosion current density of 2.2 A/cm 2 and low corrosion rate of 0.15 mm/year. The antibacterial property improved for both Staphylococcus aureus ( S. aureus ) and Escherichia coli ( E. coli ) by addition of Ag. The antibacterial rates were more than 99% when Ag content is up to 1 wt.%. The biodegradable Zn-Mg-Ag alloys with high antibacterial behavior show great potential in medical devices.