Influence of Electrolyte Movement on Measured Electrochemical Noise

In the present study, the influence of movement of solution on the characteristics of measured electrochemical noise (EN) was investigated. For this reason, measurements were performed in still solution, as well as in movement of the electrolyte. To relate measured EN to the development of corrosion processes, digitized images of electrodes were recorded continuously during these measurements. It was found that the characteristics of EN, in general, change significantly with strong movement of the solution: stirring or laminar flow. Results of this study confirmed that the main source for this change is transformation of corrosion processes: in a still solution, the corrosion process tends to be localized, whereas during strong movement of the electrolyte, this tendency is oriented toward uniform corrosion. It was established that the direct effect of the electrolyte movement on measured EN (modulation of signals caused by spatiotemporal flow disturbances) is small.