Surface Characterization of Magnesium Anodized in a 10M KOH Electrolyte
Magnesium (Mg) is a promising implant material for orthopedic applications due to its biodegradability and desirable mechanical properties. However, in order for Mg to have widespread clinical applications, engineering solutions that address the rapid degradation in physiological environments and promote bone-forming activity are needed. The objective of this study was to develop an anodization process using a toxicant-free electrolyte to modulate nanoscale surface features and surface chemistry on Mg. Anodic polarization and potentiostatic anodization tests were used to evaluate the effect of applied potential on surface morphology of Mg in a 10 M KOH electrolyte. Nucleation of oxides as a function of anodization duration was also investigated in order to optimize the synthesis process. The alkaline electrolyte used for anodization of Mg offers an alternative to commercial processes that use hazardous elements. The anodized samples were annealed to investigate the effect of thermal treatments on surface morphology and chemical composition. The nanostructure and chemical composition of the anodized and annealed Mg substrates were characterized using scanning electron microscopy and energy dispersive X-ray spectroscopy. Our results showed that the nanostructures and chemical composition of anodically-generated oxide layers on Mg are specific to each oxidation process in a 10 M KOH electrolyte. Furthermore, results indicated that anodization durations of two hours generated surface oxide layers with homogeneous topography on the Mg substrates atapplied potentials of 0.5 V, 1.5 V and 2 V.. This study showed a promising approach for creating nanoscale surface features on Mg for improved bioactivity and degradation property.
B. Mishra, M. Ionescu and T. Chandra
C. Miller et al., "Surface Characterization of Magnesium Anodized in a 10M KOH Electrolyte", Advanced Materials Research, Vol. 922, pp. 513-518, 2014