Enhanced Corrosion Resistance in Artificial Saliva of Ti6Al4V with ZrO2 Nanostructured Coating

• Published in: Journal of the Electrochemical Society 2015-09, Vol.162 (11), p.D3090-D3100
• Main Authors: Machado-López, M. M., Faure, J., Espinosa-Medina, M. A., Espitia-Cabrera, M. I., Contreras-García, M. E.
• Format: Article
• Language: English
• ISSN: 0013-4651
• DOI: 10.1149/2.0231511jes

The increased use of the Ti6Al4V alloy as prosthetic material has been questioned by different authors who have confirmed its ion release when undergoing a corrosion attack by body fluids. In this work the coating of the Ti6Al4V alloy with nanostructured Zirconia is proposed through the colloidal electrophoretic deposition method (CEDP). The coatings were thermally treated at 450°C, 500°C, 600°C, 650°C and 700°C. The effect of the thermal treatment temperature on the morphology and phase content was evaluated by field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). Corrosion resistance of the Ti6Al4V alloy and the ZrO2/Ti6Al4V system was evaluated by Tafel extrapolation, polarization resistance and electrochemical impedance spectroscopy in artificial saliva media with a pH of 7.4 at a temperature of 37°C, using an aereated electrochemical cell to simulate human buccal conditions. The Ti6Al4V alloy showed good corrosion resistance by forming a passivation TiO2 layer on the metal surface, but there was an increase in the resistance when the Ti6Al4V alloy was coated with ZrO2. It showed lower values in the icorr, corrosion rate and ion release, a higher impedance modulus and a substantial polarization resistance after 24 hours.