Corrosion Of Titanium And Corrosion And Electrochemical Studies

Titanium is a multi-purpose structure of metals; Titanium is a new functional material and an important biological material. Due to the significant strategic value of titanium and status in the national economy, titanium will become "third metal," after the rise of iron titanium, aluminum. The 21st century will be "the century of titanium". Therefore, to promote the use of the advantages of playing the role of titanium properties, for the promotion of industrial development and enhance the vitality of product competition plays an important role, but also the direction of development of modern technology. 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 are an important research subject. Sodium fluoride can corrode seriously metal equipment. Therefore, there is very important for the industrial field aboat the corrosion and protection research of sodium fluoride system. In this paper, the corrosion, inhibition function and mechanism of titanium electrode in the sodium fluoride system aer studied with cyclic voltammetry, steady state polarization method and electroehemical impedance method. The experiment result1 as follows:In sodium perchlorate solution by adding sodium fluoride, Made by cyclic voltammetry curves we can get that:When the odium fluoride concentration added, anode summit currents augment, corrosion of the titanium electrode gradually increased, anodic dissolution of titanium is easier. Sodium fluoride solution on the titanium electrode has a strong corrosive. Prior to joining after sodium molybdate and sodium fluoride system, with the accession to the concentration of slow-release agent increases, the anode current decreases, Description phosphate and molybdate complex with titanium electrode material can be formed on the surface layer of protective film, you can slow down the anodic dissolution of titanium electrodes.Research results by steady-state polarization test showed that, corrosion potential was negative-shifted; corrosion current was changed big with the concentrated increase of sodium fluoride. All these phenomenon showed that the corrosion of titanium electrode become aggravation with the increase of the concentration. When add sodium molybdate and sodium phosphate into the system of sodium fluoride, corrosion potential was positive-shifted, corrosion current was changed small, so this system can relieve the corrosion of titanium. The addition of remixed corrosion inhibitor is much more excellent than that of the single corrosion inhibitor, when the proportion of remixed corrosion inhibitor was 3:7, the effect of corrosion inhibitor was best and the inhibitor efficiency can reach to 71.8%.Electrochemical impedance tests showed that the greater the concentration of sodium fluoride the smaller the diameter of capacitance semicircle. Rs,Rt become small with the concentrated increase of sodium fluoride, the extent of corrosion become aggravation, the reason of this phenomenon was that the increase of the fluoride accelerated the corrosion of the titanium electrode. Sodium molybdate and sodium phosphate are of cooperative corrosions, under the condition of total additive concentration was 0.8g/L, when the proportion of sodium phosphate and sodium molybdate was 3:7, the cooperative corrosion was best and much better than that of the single corrosion of sodium molybdate.