The Dissolution Mechanism of Iron in Chloride Solutions

We have measured the polarization curve and the electrochemical impedance for the dissolution of iron in sodium chloride solutions of varying p H of [ , ] . The polarization curves are comparable with those of previous workers and exhibit two distinct Tafel slopes: 75 mV/s at low polarization, and 40 mV/decade at high polarization for . The impedance diagrams exhibit a high frequency capacitive loop, followed by one inductive loop at low overpotentials, and a further inductive loop at high overpotentials. We have interpreted these phenomena in terms of two parallel dissolution paths.