Biodegradable Mg-Zn-Ca-Y glass forming alloy with an amendment in mechanical properties and corrosion resistance

Abstract

For orthopedic application, the biodegradable implant material should possess a combination of good mechanical strength, reasonable ductility and optimal corrosion resistance. The key challenge in developing magnesium (Mg) based metallic glasses as viable orthopedic implant is to improve its mechanical properties as well as its corrosion resistance. In this work, an attempt has been made to improve the mechanical behavior and corrosion resistance of Mg-Zn-Ca glass forming alloy using yttrium (Y) addition. Mg66Zn30Ca4 metallic glass and a novel Mg-Zn-Ca-Y glass forming alloy with nominal composition of Mg52.5Zn40.5Ca5Y2 were synthesized. The effect of Y addition on the glass forming ability, mechanical behavior and corrosion properties of Mg-Zn-Ca metallic glass was investigated using X-ray diffraction, differential scanning calorimetry, hardness tests, compressive tests and electrochemical studies. Mg66Zn30Ca4 was completely amorphous while the glass forming ability reduced with Y addition. Enhancement in mechanical properties and corrosion resistance were observed upon addition of Y. Enrichment of mechanical behavior and corrosion resistance in Mg52.5Zn40.5Ca5Y2 alloy was attributed to the presence of Mg12YZn LPSO and Mg3YZn6 icosahedral phases formed due to the addition of Y.