Fabrication and corrosion behavior of TiO2 nanotubes on AZ91D magnesium alloy

The major drawback of magnesium alloys in biomedical applications is the rapid degradation rate and the lack of biological activity. In this study, TiO2 nanotubes were fabricated on the surface of AZ91D magnesium alloy (TiO2-Mg) to overcome such limitations. The corrosion behavior of TiO2-Mg nanotubes was studied in simulated body fluid solution using open circuit potentials (OCP), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests. The high polarization resistance and open circuit potentials of TiO2-Mg nanotubes indicate the formation of highly stable TiO2 layer in simulated body fluid than that of titanium layer on magnesium alloy (Ti-Mg). TiO2 nanotubes on AZ91D magnesium alloy (AZ91D) can effectively decrease the degradation rate of magnesium alloy, thus can be further applied in orthopedic implants.