Mechanical Performance of Biodegradable Magnesium Alloy after Immersion in Simulated Body Fluid

Abstract

Magnesium (Mg) alloys, with a light weight, favorable strength, biodegradability, and biocompatibility, have the potential to be employed as biomedical implants; however, rapid degradation prevents their usage because it lowers their mechanical properties. In this study, ZE41A Mg alloy was investigated for mechanical properties after processed with powder mixed wire electric discharge machining (PMWEDM) and hydroxyapatite (HA) coating. Zinc metal powder is mixed with dielectric medium for PMWEDM process and electrochemical deposition (ECD) technique is used for preparing HA coating. Field emission scanning electron microscopy (FE-SEM) was employed to study surface morphologies. Bending/flexural and compression testing of polished, PMWEDMed, and HA-coated samples were performed before and post immersion in simulated body fluid (SBF). Results reveal a loss of bending (σ_b) and compressive (σ_c) strengths when immersed samples were compared with non-immersed ones. Immersed samples showed a decline in mechanical strengths as a result of SBF degradation. PMWEDMed samples exhibited the maximum loss of strength among all three.