Development of Biomedical Mg–1.0Ca–0.5Zn–0.1Y–0.03Mn (at%) Alloy by Rapidly Solidified Powder Metallurgy Processing

Abstract

We investigated the alloy composition of Mg–Ca–Zn alloys suitable for rapidly solidified powder metallurgy (RS PM) processing and tried to develop biomedical Mg–Ca–Zn RS PM alloys with high strength, high ductility, and high corrosion resistance. The alloy composition suitable for RS PM processing was Mg–1.0Ca–0.5Zn (at%) in ternary Mg–Ca–Zn alloys. An Mg–1.0Ca–0.5Zn RS PM alloy with combined additions of 0.1 at% Y and 0.03 at% Mn exhibited excellent performance with a tensile yield strength of 376 ± 17 MPa, an elongation of 14.1 ± 3.1%, and a corrosion rate of 0.46 ± 0.04 mm·year⁻¹ when immersed in HBSS, resulting in the achievement of our target properties. Especially the yield strength of the Mg–1.0Ca–0.5Zn–0.1Y–0.03Mn RS PM alloy developed in this study was higher than that of previously reported Mg–Zn–Ca(–Mn–Zr) or Mg–Ca–Zn(–Mn–Zr) ingot metallurgy (IM) alloys, which were produced by single extrusion, double extrusion or severe plastic deformation (SPD) of cast ingots.

Comparison of the tensile yield strength and elongation of the biomedical Mg–1.0Ca–0.5Zn–0.1Y–0.03Mn (at%) rapidly solidified powder metallurgy (RS PM) alloys developed in this study, with various high strength Mg–Zn–Ca(–Mn–Zr) or Mg–Ca–Zn(–Mn–Zr) ingot metallurgy (IM) alloys. The RS PM alloy developed in this study has higher yield strength than previously developed biomedical high-strength Mg–Zn–Ca(–Mn–Zr) or Mg–Ca–Zn(–Mn–Zr) IM alloys.