Synthesis of Magnesium-Based Alloys by Mechanical Alloying for Implant Applications

The biocompatibility and biodegradability of magnesium (Mg), along with its lightness, make magnesium-based materials promising for use in the biomedical industry. In this work, ternary Mg–Zn–Ca alloys were manufactured for biomedical applications using mechanical alloying (MA). The objective of this work was to study the effect of milling time on the produced ternary alloys Mg65–Zn30–Ca5 and Mg70–Zn25–Ca5 (percentages by weight), the degradation of the alloys in synthetic human fluids, and their generated cytotoxicity. The Mg-based alloys were synthesized in a planetary ball mill under an argon atmosphere using stainless-steel containers and balls with a milling regimen of 400 rpm for 2, 5, 10, 15, and 20 h. The powders obtained after MA were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD), which verified that ternary Mg–Zn–Ca alloys can be obtained using MA. The XRD refinement analysis of the samples showed the presence of a MgZn intermetallic phase. Electrochemical tests showed that the corrosion resistance and corrosion current density of Mg65–Zn30–Ca5 and Mg70–Zn25–Ca5 alloys improved compared to those of pure Mg. Cytotoxicity testing was conducted using the Sulforhodamine B (SRB) assay, which revealed that the alloys did not exhibit cytotoxicity toward human fibroblast cells. Mg65–Zn30–Ca5 and Mg70–Zn25–Ca5 alloys show good potential to be used in biomedical applications.