Enhancements of Corrosion Behavior and Bioactivity in HA-TiO۲ Nanostructured Composite Coatings Fabricated by Electrophoretic Deposition

چکیده مقاله

In the present study, the HA-TiO2 nanostructured composite coatings with 0, 10 and 20 wt% TiO2 were fabricated by electrophoretic deposition at 20 V for 3 min. Electrochemical corrosion behavior of the samples was conducted in SBF solution at 37oC by potentiodynamic polarization tests. The corrosion parameters were obtained by Tafel extraploation. For the effect of titania on apatite formation, electrochemical impedance spectroscopy after in-vitro tests were conducted on coatings. The recorded impedance spectra were modeled by fitting the data with an equivalent circuit. Based on the electrochemical corrosion behavior of samples in SBF solution at 37˚C, the corrosion current density and corrosion rate significantly decreased by implementation of TiO2 while corrosion potential and linear polarization resistance were increased. Also, the EIS analysis revealed that the total resistance of HA-20 wt% TiO2 sample is higher than that of other samples. The accelerated apatite formation on HA-20 wt% TiO2 sample corresponding to ICP analysis was attributed to the higher wettability of the coating surface.