Electrochemical behavior and corrosion resistance of Ti–15Mo alloy in naturally-aerated solutions, containing chloride and fluoride ions

Abstract

The electrochemical behavior and corrosion resistance of Ti-15Mo alloy to applications as biomaterials in solutions 0.15 mol L -1 Ringer, 0.15 mol L -1 Ringer plus 0.036 mol L -1 NaF and 0.036 mol L -1 NaF (containing 1,500 ppm of fluoride ions, F -) were investigated using open-circuit potential, cyclic voltammetry, and electrochemical impedance spectroscopy techniques, X-ray photoelectron spectroscopy and scanning electron microscope. Corrosion resistance and electrochemical stability of the Ti15Mo alloy decreased in solutions containing F -ions. In all cases, there were formation and growth of TiO 2 and MoO 3 (a protector film), not being observed pitting corrosion, which might enable Ti-15Mo alloys to be used as biomedical implant, at least in the studied conditions, since the electrochemical stability and corrosion resistance of the passive films formed are necessary conditions for osseointegration.

Influence of fluoride on the electrochemical behvior of a new synthesized Ti-10Ta-2Mo alloy for biomedical applications

“…For example, A. V. Rodrigues [37] found when studying Ti15Mo in Ringer solution at 25°C that the passive plateau currents are between 300µA/cm 2 and 800µA/cm 2 which are very higher than those obtained in our study, varying between 12.26µA/cm 2 and 25.76 µA/cm 2 , in addition our study was carried out at 37°C. The Ti-10Ta-2Mo shows a better passive behavior than other materials richer in molybdenum.…”

Bioactive layers based on black glasses on titanium substrates

“…Relatively high current densities arise from the large real surface area (due to coarse grinding of the substrate) relative to the geometric area used for normalizing of the measured currents. At the potential of approximately 2.5 V vs SCE the current increased significantly, which is due to oxidation of Ti 3+ ions to Ti 4+ ions 52 and partly due to gaseous oxygen evolution, which according to Pourbaix diagram for Ti commences at 0.96 V. 53 In the curve recorded for the Ti coated with black glass the current densities up to 2 V vs SCE in the forward scan are much lower than those measured for the uncoated Ti. However, above 2 V vs SCE the current density spikes up to 12 mA/ cm 2 , which is substantially higher compared to the uncoated Ti.…”

Ti-Mo alloys: corrosion study in solutions simulating commercial gels

“…There were formation and growth of the anodic oxide film in the region a during the increase of the anodic current density, and the passivation of the materials in the region b. It was reached a current plateau and there was no transpassivation in potentials up to 8 V [6,[13][14] . There was also no pitting corrosion in all the Ti-Mo alloys exposed in the different solutions during the potential scans, suggesting their high resistance even in the presence of fluoride ions, which did not avoid the formation of the passive film probably due to the small amount of HF in the solution, nevertheless these ions can dissolve the passive film due to the formation of TiF3, TiF4 and TiOF2 [13] , expressed in the (1), (2) and 3reactions: prevent dental caries [14][15][16] .…”

“…The current density started increasing at 4 V, which meant the existence of a parallel reaction of water oxidation and release of O2. According to the Pourbaix diagram, the oxidation reactions of water above 1.2 V is enabled to be occurred, therefore, explaining that release of O2 close to 4 V [6,15] .…”

“…Under the norm ASTM F 2066, the Ti-15Mo alloy was approved to be applied in devices as implants for humans [5] . According to Rodrigues et al (2015), a stable passive oxide film was formed on the Ti-15Mo alloy surfaces, which were exposure to naturally-aerated solutions containing chloride and fluoride ions that caused a decrease in corrosion resistance [6] . The literature Copyright © 2018 Aline Varella Rodrigues et al doi: 10.24294/jpse.v1i4.897 EnPress Publisher LLC.This work is licensed under the Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0).…”