Investigation of Microstructural, Mechanical and Corrosion Properties of Biodegradable Mg-Sn-Y Alloys

In this study, biodegradable magnesium alloys were produced using the high pressure die casting (HPDC) technique. Effects of Y addition on microstructure, mechanical properties and corrosion behaviors of as-cast Mg-4Sn-xY (x = 0, 1, 2, 4 wt.%) alloys are investigated. The surface morphology of the alloys was examined using field emission scanning electron microscopy (FE-SEM) and the microstructure was examined using energy dispersive spectroscopy (EDS), respectively. Tensile and hardness tests were carried out to examine the mechanical properties. Microstructural studies have shown that the addition of yttrium causes a reduction in the grain size of the alloy and the formation of Sn3Y5 and MgSnY intermetallic compounds with high melting temperature, as well as Mg2Sn intermetallic. While, the maximum tensile strength value is achieved with the addition of 1% yttrium by weight, the increase in yield strength, elongation percentage and hardness values continue with the addition of more yttrium. Corrosion tests have shown that the addition of yttrium to the Mg-Sn alloy increases the corrosion resistance of the alloys due to microstructural changes. The Mg-4Sn-4Y alloy is found to be a promising biodegradable magnesium alloy especially for orthopedic applications.