Studies of corrosion behaviors for anodized metal in H3PO4/H2O2 solutions

• Main Authors: Yu Yu Tsai, 蔡育佑
• Other Authors: W. C. Say
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/33348461677461596110

碩士 === 國立臺北科技大學 === 材料及資源工程系碩士班 === 90 === Thickness of the oxide filmed formed on the surfaces of anodized titanium alloys may thicken with increasing of the applied voltage. In this study, titanium alloys were anodized in 1N phosphoric acid with applying voltages of 30(v), 60(v), and 90(v) respectively. The anodized specimens were then immersed in the mixture solution of 1N phosphoric acid and 10% hydrogen peroxide. Hydrogen peroxide is not stable that it could be decomposed to water and oxygen spontaneously at room temperature. This could be simulated for application of titanium alloys in the biocompatible environments. The auger electron spectroscopy (AES) was used for the elements distribution of passive oxide film formed on the surfaces of the anodized specimens. Corrosion behaviors of the oxide film were investigated with technique of electrochemical impedance spectroscopy (EIS). The spectra were interpreted in terms of equivalent circuit based on a plausible physical model with the circuit elements representing electrochemical properties of the films during the immersion. Titanium ion concentrations in the residual solutions after 45 days of immersion were analyzed with UV/VIS and atomic adsorption spectra. The results showed that anodizing of titanium alloys at 60 volt of applied potential provided the most stable condition in the mixture solution.