Microstructures and mechanical properties of biodegradable magnesium-zinc alloy fabricated by spark plasma sintering

Abstract:

Biological Mg-x(2~8) wt%Zn alloys were fabricated from pure magnesium and zinc powders using high-energy ball milling and spark plasma sintering method. The microstructure, mechanical properties and corrosion performance of the biological Mg-Zn alloys were investigated. The results reveal that the sintered samples have a compact and homogenous internal structure. The mechanical properties, i.e. hardness and compression strength increased with increasing Zn content, and reached the maximum (69.0 Hv_0.1 and 379.5 MPa) at the 6wt% of Zn. The corrosion potential increased with increasing Zn content, while representing opposite tendency in current density tested in the SBF, and achieved the maximum and minimum respectively at the 6wt% of Zn. Moreover the corrosion mode in SBF transformed from severly crevice corrosion and pitting corrosion into particle spalling, finally presening a internal corrosion of particles and light pitting corrosion with the Zn content increased.

Key words:bio-Mg-Zn alloy; Spark plasma sintering; high-energy ball milling; mechanical properties; corrosion properties