Acta Metallurgica Sinica (English Letters) ›› 2010, Vol. 23 ›› Issue (5): 343-350.DOI: 10.11890/1006-7191-105-343

• 研究论文 • 上一篇    下一篇

PbO对690合金在氢氧化钠溶液中钝化行为影响的研究

李成涛1,程学群 2,董超芳 3,李晓刚4,贾志军2   

  1. 1. 北京科技大学腐蚀与防护中心511室
    2. 北京科技大学腐蚀与防护中心
    3. 北京科技大学材料学院腐蚀与防护中心
    4. 北京科技大学
  • 收稿日期:2010-05-17 修回日期:2010-07-27 出版日期:2010-10-25 发布日期:2010-10-14
  • 通讯作者: 李成涛

Study on the effect of PbO on the passive behavior of alloy 690 in sodium hydroxide aqueous solution

Chengtao LI1,2, Xuequn CHENG1,2,Chaofang DONG1,2, Zhijun JIA1,2, Xiaogang LI1,2   

  1. 1. Advanced Material and Technology Institute, University of Science and Technology Beijing,Beijing 100083, China
    2. Key Laboratory of Corrosion and Protection (Ministry of Education of China), University of Science and Technology Beijing, Beijing 100083, China
  • Received:2010-05-17 Revised:2010-07-27 Online:2010-10-25 Published:2010-10-14
  • Contact: Xiaogang LI

PDF (PC)

1253

摘要： 采用动电位极化、电化学阻抗谱与Mott-Schottky测量技术研究了690合金在含PbO和不含PbO的质量分数1%的氧化钠溶液中的钝化行为。结果表明690合金在所测试溶液中的腐蚀电化学行为具有明显的差异。动电位极化曲线显示：在含PbO的条件下，腐蚀电流密度比不含PbO的测试结果要大。这可能是由于极化的初始阶段金属Pb在试样表面的沉积造成的。电化学阻抗谱表明：在不含PbO溶液中的阻抗模值大于含PbO的溶液中的阻抗模值。Mott-Schottky曲线的测试结果表明：含PbO溶液中的曲线斜率小于含PbO溶液的。这可能是由于试样表面形成的双层结构的钝化膜中Cr的贫化造成的。

关键词: 690合金, 电化学阻抗谱, 氧化铅, Mott-Schottky曲线, 钝化膜

Abstract: The corrosion behaviors of alloy 690 in 1 wt pct sodium hydroxide aqueous solutions with and without PbO were characterized by electrochemical measurements, including potentiodynamic polarization, electrochemical impedance spectroscopy and Mott-Schottky measurement. The results reveal that there is a great difference between the corrosion behaviors of alloy 690 in the two tested solutions. The corrosion current density in PbO-containing solution is higher than that in the solution without PbO, which may be attributed to the anodic dissolution of metallic lead deposited at the early stage of polarization. The electrochemical impedance of the specimen in PbO-free solution is higher than that in the solution containing PbO. The slope of the Mott-Schottky curve in Pb-containing solution decreases notably compared with that in the Pb-free solution, which can be interpreted by the chromium depletion in the duplex structure of passive films.

Key words: Alloy 690, Electrochemical impedance spectroscopy, PbO, Mott-Schottky curve, Passive film

中图分类号: