Effect of temperature and dissolved oxygen on the passivation behavior of Ti–6Al–3Nb–2Zr–1Mo alloy in artificial seawater

Abstract

The effects of temperature and dissolved oxygen on the passivation behavior of Ti–6Al–3Nb–2Zr–1Mo alloy in artificial seawater are investigated. The increase of temperature increases the anodic and cathodic current density, and also increases the field strength and zero field activation energy for oxygen vacancy motion. The decrease of dissolved oxygen concentration inhibits the transformation of titanium oxide and results in the disappearance of the anodic peak. Meanwhile, the passive current density increases in the deaerated environment because of the increase in the point defect density and diffusion rate. The passive film exhibits n-type semiconductivity, and oxygen vacancy is the main point defect.

Keywords

• Titanium alloy
• EIS
• Passivation
• Electrochemical behavior