Abstract
Simulations on current fluctuations observed during anodic polarization below the pitting potential have been made assuming several different shapes of current spikes. The power spectra calculated by FFT method were characterized by the power at the lowest frequency G0(f), the break-point frequency on the spectrum f0, and the slope m. It was revealed that the power G0(f) corresponded to the energy of the spikes, so it depended upon the number of spikes (rate of pit embryo formation), their maximum amplitude and the life times. The slope m was determined by the shape of each spike, such as m=1 for rectangular and saw tooth shape spikes and m=2 for triangles. The break-point frequency f0 which depended slightly upon the life time and the number of spikes was considered as an index of the duration in which relatively many spikes were observed.
