Abstract
Hot molten-salt corrosion can cause serious metal degradation in boiler plant, incinerators, and furnaces. In this research, electrochemical-impedance and electrochemical-noise techniques have been evaluated for the monitoring of hot-corrosion processes in such plants. Tests have been carried out on Ni-1 % Co and Alloy 800, a commercial material of interest to operators of industrial plants, utilizing a bulk molten-salt environment and also a simulated combustion test, where thin films of molten salt were established on the alloy surfaces. Electrochemical-impedance and electrochemical-noise data were compared with the results of metallographic examination of the test alloys and showed reasonable correlation between the electrochemical data and the actual degradation processes. Current-noise analysis gives valuable information on the initiation stages of hot corrosion, while impedance measurements can detect propagation or rapid corrosion of the base metal. This preliminary work indicated that the electrochemical techniques show considerable promise as instruments for the monitoring of high-temperature corrosion processes.
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Gao, G., Stott, F.H., Dawson, J.L. et al. Electrochemical monitoring of high-temperature molten-salt corrosion. Oxid Met 33, 79–94 (1990). https://doi.org/10.1007/BF00665670
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DOI: https://doi.org/10.1007/BF00665670