Electrochemical Corrosion Of Titanium

Titanium is a multi-purpose structure of metals,in the past 10 years,the national economy in all fields,particularly in the oil,chemical,aviation,medical,surface treatment,and other fields have been growing wider range of applications.Although titanium is an easy-passivation and corrosion resistance of strong metal materials,but in some erosion of the ion or containing compounds in the environment,because the surface oxide film TiO2 damage to the basement and lost its protective titanium,and lead Titanium corrosion.Therefore titanium Corrosion and Protection of the problem has attracted extra attention,and electrochemical materials is an important research subject.By using linear sweep voltammetry,cyclic voltammetry,A.C. impedance spectroscopy,and other technology,in the 1 M perchloric acid solution.and 0.1 M sodium perchloride acid solution within a relatively wide potential range,investigated the anodic passivation behavior and some process of TiO₂ film.on several common anions(F^-,S₂0₃^2-,EDTA^2-)on titanium corrosion - Protection of behavior and performance impact.The results of this study in-depth understanding of the medium conditions on the corrosion behavior of titanium and titanium corrosion protection is an important reference value.In this work,the behavior of oxygen evolution and some other related electrode processes occurring at anodically grown TiO₂ films on titanium were investigated within a relatively wide potential range by electrochemical measurements in 1 M perchloric acid solution.For the formation of the oxide film,three potential regions(two passive regions and the film breakdown region)were selected.The changes both in surface properties mainly caused by oxygen evolution, and in bulk properties mainly caused by increased potential,were taken into account for the observed different oxygen evolution behavior.The origin of a cathodic current peak at -0.2 V revealed in cyclic voltammograms was attributed tO the reduction of the oxygen atoms adsorbed/absorbed at the oxide film surface,which were generated during anodic oxygen evolution.In the neutral solution,we investigated the affect to the anodic dissolution of the titanium in the sodium fluoride and the sodium thiosulfate and the EDTA in 0.1 M sodium perchloride acid solution.It is shown that sodium fluoride and sodium thiosulfate accelerate the anodic dissolution of the titanium,and sodium fluoride exhibits stronger effect than sodium thiosulfate for promoting the corrosion of titanium.In addition,the dissolution and corrosion of titanium are enhanced with the increase of the concentration of sodium fluoride or sodium thiosulfate accretion presented in solution.On the other hand,it is found that EDTA acts as an inhibitor to the corrosion of the titanium.This could be attributed to the formation of a protective complex film at the titanium surface due to the complex reaction of EDTA with titanium,which retards the dissolution either of metal titanium or the passive oxide film on titanium.The results presented in this study would supply some important information for further studying the effect of corrosive compounds and species on the corrosion and anticorrosion of titanium in practice uses.