Electrochemical stability of binary TiNb for biomedical applications

The Ti-Nb alloy binary system has been widely studied with regard to biomedical applications due to the high biocompatibility and excellent mechanical properties of the alloys. Regarding physical-chemical stability, Ti-Nb alloys maintain the properties of Ti metal, which is highly resistant to corrosion in aggressive media due to a spontaneous stable oxide layer (TiO2) formed on its surface. The objective of this study was to evaluate the corrosion resistance of the Ti-40Nb alloy in artificial blood. The thermodynamic stability was studied using the open circuit potential technique and the corrosion resistance was assessed by potentiodynamic measurements and electrochemical impedance spectroscopy. The electrochemical results indicated that the Ti-40Nb alloy has high corrosion resistance and good thermodynamic stability, with an OCP of around −485 mV, and the alloy remained electrochemically stable in potentiodynamic conditions with initial and final potentials of −1.0 V to +2.0 Vsce, respectively, in low current densities (~µA cm−2) with an absence of hysteresis, aspure Ti. The results obtained showed that this specific alloy has the potential to be used in biomedical applications.