Electrochemical Impedance of Molten Salts Induced Hot Corrosion

Authors

Chaoliu Zeng, Center for Intelligent Materials Research, College of Chem. and Molecular Engineering,Peking Univ., Beijing 100871);
Weitao Wu, State Key Laboratory for Corrosion and Protection, Institute of Corrosion and Protection of Metals, Academia Sinica, Shenyang 110015)Zhang Jianqing(Dept. of Chem., Zhejiang Univ., HangZhou 310027);
Jianqing Zhang, State Key Laboratory for Corrosion and Protection, Institute of Corrosion and Protection of Metals, Academia Sinica, Shenyang 110015)Zhang Jianqing(Dept. of Chem., Zhejiang Univ., HangZhou 310027);

Corresponding Author

Chaoliu Zeng

Abstract

Electrochemical impedance technique was employed to study corrosion behaviors of Ni-3Al, IN100 and IN738 alloys in molten (Na, K, Li)_2SO_4 at 700 ℃. The Nyquist plots for Ni-3Al and IN100 alloys have the characteristics of diffusioncontrolled reaction. But, the corrosion reaction for IN738 alloy is not controlled by the diffusion of oxidants. The equivalent circuits were proposed, and the parameters in circuits were also calculated. Ni-3Al and IN100 alloys suffer from catastrophic corrosion due to the formation of a porous corrosion layer. IN738 alloy has excellent corrosion resistance because of the formation of a protective oxide scale.

DOI Link

https://doi.org/10.61558/2993-074X.2672

Publication Date

1998-02-28

Online Available Date

1998-02-28

Revised Date

1998-02-28

Received Date

1998-02-28

Recommended Citation

Chaoliu Zeng, Weitao Wu, Jianqing Zhang. Electrochemical Impedance of Molten Salts Induced Hot Corrosion[J]. Journal of Electrochemistry, 1998 , 4(1): Article 7.
DOI: 10.61558/2993-074X.2672
Available at: https://jelectrochem.xmu.edu.cn/journal/vol4/iss1/7

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