In-vitro investigation of magnesium-based biodegradable metallic implants

In this study, Mg-based alloys produced using mechanical alloy and hot pressing. The biodegradability of Mg-based alloys was tested in-vitro in the SBF solution. SBF (artificial body fluid) is almost equal to human body blood plasma with ion concentrations. Six different implants were produced. They were placed in SBF solution and then their corrosion resistances were followed. During the process, visual changes of the implants were observed, pH, Mg and Zn ion concentrations of SBF solutions and mass, dimensional changes of degraded implants in solutions were measured. As soon as, implants were placed in SBF solutions, gas outlet of H2 was observed, because of Redox reaction, which took place between implants and SBF. The composites in SBF remained between 1-360 hours and Zn% 2.35 and 3.10 had the longest degradation time when compared to others. Therefore only three of the composites Zn% 0 (1h), 2.35 (360h) and 3.10 (192h) were selected for the further tests, SEM and mechanical control tests. Hydroxyapatite layer was observed around the alloy containing 3.10% Zn. Keywords: Magnesium, Zinc, Mechanical alloying, biodegradable implant, SBF.