The Corrosion Behavior of T2 Brass in Power Plant Generator Stator Cooling Water

 Bing Feng Bing Feng , Fanglin Zha Fanglin Zha , Li Li Li Li , Jiaqiang Wei Jiaqiang Wei , Kai Liu Kai Liu
Российский электрохимический журнал
Abstract / Full Text

In this paper, the growth process of T2 brass passive film in generator cooling water was studied, the effect of CO2’s leakage on the crystal structure and anti-corrosion performance of passive film was analyzed, and we were trying to repair the passive film by adjusting pH of solution. Electrochemical Impedance Spectroscopy (EIS), Potentiodynamic Polarization (PP), Potentiostatic Scan (PS), Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS) were used in this paper. The test results showed that a thin and dense Cu2O passive film was formed on the surface of T2 brass after immersed in the cooling water for 2 days. And then a loose CuO outside layer was formed gradually, during this period the Cu2O was further oxidized to be CuO, the dense structure of the inner Cu2O layer was thus damaged. Finally a double-layer passive film consisted by Cu2O and CuO was formed at the 24th day of immersed. Corrosion pits and cracks appeared on the outside passive film after erosed by CO2. The anti-corrosion performance of the passive film cannot be completely restored by self in alkaline solution.

Author information
  • Hunan Province Key Laboratory of High Efficient and Clean Thermal Power Technology, 410007, Changsha, China

    Bing Feng, Fanglin Zha & Kai Liu

  • State Grid Hunan Electric Power Corporation Research Institute, 410007, Changsha, China

    Bing Feng & Jiaqiang Wei

  • Hunan Xiangdian Test Research Institute Co. Ltd., 410004, Changsha, China

    Fanglin Zha & Kai Liu

  • Hunan Province Maternal and Child Health Hospital, 410005, Changsha, China

    Li Li

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