Inhibitor efficiency inside small crevices investigated by electrochemical noise analysis

The Electrochemical Noise Analysis (ENA) is a novel technique employed to investigate dynamic properties of electrochemical systems. The influence of chromate inhibitors on the corrosion activity of an AA 2024 surface in a chloride containing sodium solution was studied by the measurement of current noise under potential control. The noise analysis clearly shows the efficiency of the chromate inhibitor on the crevice corrosion as well as the sufficiency of the ENA as a useful tool as an inhibitor screening process. The measurement under crevice condition was carried out in-situ in an artificial crevice.