Influences of pH Values' Changes on the Oxide Film of U-0.79 wt.% Ti Alloy in Aqueous SolutionA Combined Study of Traditional Electrochemical Tests and Scanning Reference Electrode Technique

被引：3

作者：

Cai, Dingzhou ^{[1
]}

Zhang, Dongxu ^{[1
]}

Chen, Xianglin ^{[1
]}

Wu, Haoxi ^{[1
]}

Wang, Ming ^{[1
]}

Sang, Ge ^{[1
]}

Li, Yingru ^{[1
]}

机构：

[1] China Acad Engn Phys, Inst Mat, Jiangyou 621907, Mianyang, Peoples R China

来源：

COATINGS | 2019年 / 9卷 / 04期

基金：

美国国家科学基金会; 中国国家自然科学基金;

关键词：

uranium-titanium alloy; corrosion; pH value; electrochemical tests; scanning reference electrode technique; PITTING CORROSION; DEPLETED URANIUM; WATER-VAPOR; OXIDATION; DISSOLUTION; TITANIUM; BEHAVIOR; CHLORIDE; SURFACE; OXYGEN;

D O I：

10.3390/coatings9040224

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

By combining traditional electrochemical tests including Tafel extension method and Mott-Schottky fitting, spectroscopic ellipsometry (SE) and a micro-region analysis technique, which is an integrated system of a scanning reference electrode technique and scanning tunneling microscope (SRET/STM), the changes in properties of the oxide film that formed on the surface of the U-0.79 wt.% Ti alloy (U-Ti alloy in short) in 0.1 M NaNO3 were carefully investigated as the pH value changed. The results show that the properties of the oxide film are strongly pH-dependent. The corrosion potential and corrosion current density decrease with the increasing pH value. The oxide film appears to be a p-type semiconductor at pH = 2.43. However, the transition from n-type to p-type for the oxide film as a semiconductor is observed with the increasing applied potential when the solution pH value varies from 2.43 to 7.0. The oxide film presents as an n-type semiconductor when the pH value varies from 7.0 to 11.44. In addition, during the transition of the pH, the roughness and the number of active points of the alloy surface decreases while the oxide film is thicker. It can be concluded that the corrosion resistance of the oxide film formed on the U-Ti alloy surface is enhanced in neutral or alkaline solutions.

引用

页数：15