Microstructure and corrosion behaviors of biodegradable Mg-1Zn-1Zr-xSn alloys prepared by powder-in-tube rolling

The objective of the present study was to investigate the effects of Sn addition on the mechanical and corrosion properties of Mg-1Zn-1Zr-xSn (x = 1, 2, 3, 4, 5 wt.%) alloys prepared by powder-in-tube rolling (PTR) method. The PTR-treated Mg alloys reached 98.3% of theoretical density. The hardness of the alloy increased with Sn addition. Two main intermetallic phases, Mg₂Sn and Zn₂Zr₃, were formed in the alloys. The Mg₂Sn intermetallic particles were observed along the grain boundaries, while the Zn₂Zr₃ particles were distributed in the Mg matrix. The addition of 1 wt. % Sn caused the corrosion potential to shift toward a more positive value, and the resulting alloy exhibited low corrosion current density.