Adrian Cailean

Electrochemical behaviour of Ti alloys containing Mo and Ta as β-stabilizer elements for dental application

Abstract Corrosion behaviour of the studied Ti12Mo and Ti60Ta alloys with the same Mo equivalent values (12%, mass fraction) together with the currently used metallic biomaterials Cp-Ti were investigated for dental applications. The electrochemical properties of the samples were examined using electrochemical techniques: such as open-circuit potential, potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS), in two electrochemical media of artificial saliva and fluoridated artificial saliva (0.1% fluoride ions, F − ) at 37 °C. Fluoride is commonly included in toothpastes, odontological gels and dental rinses to prevent dental caries and relieve dental sensitivity. The passive behaviour for all the titanium samples is observed for both solutions. The Ti60Ta alloy appears to possess superior corrosion resistance than the Ti12Mo and Cp-Ti in both electrochemical media.

Electrochemical characterization of Ti12Mo5Ta alloys in contact with saline medium

Abstract The electrochemical behaviours of unrecrystallized and recrystallized Ti12Mo5Ta alloys were compared with those of the unrecrystallized Ti12Mo alloy and commercial pure titanium (cp-Ti). Experiments were carried out using physiological 0.9% NaCl solution (pH 2.3) at 37 °C. Very low passive current densities (in order of 10−6 A/cm2) were obtained from the anodic polarization curves, indicating high resistances of all samples in acidified 0.9% NaCl solution. Scanning electron microscopy (SEM) was employed to observe the surface morphology and all sample surfaces were identically corroded, no pitting, cracks, or other defects appeared on the sample surfaces after anodic potentiodynamic polarization tests. Equivalent circuit was used for modeling the electrochemical impedance spectroscopy (EIS) data, in order to characterize the sample surface and better understand the effect of Mo and Ta addition on the cp-Ti and the effect of recrystallization. The EIS results confirm that all titanium samples exhibit passivity in physiological 0.9% NaCl solution (pH 2.3) at open circuit potential (polarization resistance is around 105 Ω·cm2). The corrosion resistance of these samples in physiological 0.9% NaCl solution (pH 2.3) at 37 °C is in the following order of recrystallized Ti12Mo5Ta> unrecrystallized Ti12Mo5Ta > unrecrystallized Ti12Mo > cp-Ti.