“…Prior to the corrosion exposures, the steel surface was cathodically polarized at -1.0 V for 5 min to remove native oxide. Cathodic polarization was followed immediately by either linear potential sweeps or constant potential corrosion exposures at -0.521 V. This potential is between the active dissolution peak of -0.60 V and the passivation potential of -0.40 V, and hence lies within the range of susceptibility to SCC and IGC [2,3,7,14]. Collection of impedance spectra was initiated immediately at the end of constant potential exposures of durations between 5 min and 20 hr.…”