The passive properties of TA10 in Coca-Cola containing oral environment

Abstract

Purpose At present, carbonated drinks such as cola are especially favored by the younger generation. But because of its acid, it often leads to tooth demineralization, resulting in “cola tooth”. However, the influence of cola on the corrosion resistance of passive film of TiA10 alloy restorative materials is rarely reported. The purpose of this study was to analysis the corrosion resistance, composition of the passive film of TA10 alloy in different concentrations of Cola. Design/methodology/approach The passive behavior of TA10 alloy in artificial saliva (AS) and Cola was studied by means of potentiodynamic polarization, electrochemical impedance spectroscopy, cyclic voltammetry, Mott-Schottky techniques and combined with X-ray photoelectron spectroscopy and Auger electron spectroscopy (AES) surface analysis. Findings With the increase of cola content, the self-corrosion current density of the alloy increases sharply, and the corrosion resistance of the passive film is the best in AS, while Rp in cola is reduced to half of that in AS. The thickness of the passive film in AS, AS +cola and cola is about 9.5 nm, 7.5 nm and 6 nm, respectively. The passive film in cola has more defects and the carrier density is 1.55 times as high as that in AS. Cola can weaken the formation process of the protected oxide, promote the formation of high valence Ti-oxides and increase the content of Mo-oxides in the passive film. Originality/value These results have important guiding significance for the safe use of the alloy in the complex oral environments.

Corrosion and passive film characteristics of 3D-printed NiTi shape memory alloys in artificial saliva

“…Based on classical semiconductor theory, Mott-Schottky Eq. ( 15) can be used to describe the linear relationship between 1/C 2 and electrode potential [39,40]. Figure 7a shows the Mott-Schottky curves of the three L-PBF NiTi immersed in artificial saliva for 168 h. When the electrode potential is higher than the flat band potential, the curves are all positive, indicating that the passive films of the L-PBF NiTi formed in artificial saliva at OCP are n-type semiconductor, which again confirms that the passive film on the NiTi-SMA surface is mainly composed of TiO 2 [29].…”