Study of the electro-corrosion resistance of titanium alloys used in implantology

The purpose of the study is to monitor the behaviour of titanium alloy (Ti6Al4V) with and without hydroxyapatite superficial coating in Fusayama-Meyer artificial saliva by electro-corrosion tests, spectrometry and scanning electron microscopy. Materials and methods: we investigated the behaviour of titanium alloys Ti6Al4V and Ti6Al4V alloy coated with HA layers in Fusayama-Meyer artificial saliva solution. The electro-corrosion tests were conducted on a Volta Master 21 potentiostat equipment. Tests were performed using the SEM scanning electron microscopy and EDAX X-ray spectrometry. Results and discussion. At the microscopic analyses it was observed an unmodified surface at the electro-corrosion tests with a good behaviour of the material in this corrosive environment and with very few reaction compounds remained after the electro-corrosion. The qualitative chemical analysis of the surface of the alloy revealed the presence on the surface of the alloy of some compounds based on potassium, chlorine and sodium, also identified through the scanning electron microscopy on the surface of the Ti6Al4V implant material. The micro-structural analysis of the surface of the Ti6Al4V implant material covered with a HA layer through PLD method shows that the material doesn't exhibit any sign of corrosion. During the electro-corrosion tests it was observed that the corrosion current presents a low value that indicates a special resistance to electro-corrosion of the material. Conclusions: both Ti6Al4V alloy and Ti6Al4V alloys coated with HA presented a good resistance to electro-corrosion.