Assessment of Fluctuations of the Electrode Potential of Aluminum in Chloride-Containing Solutions during Anode Polarization by Microcurrents

Structure of integral curves obtained by processing chronopotentiograms (CPG) of an aluminum anode polarized by a weak (at the level of one to several μA/cm2) current in a chloride-containing environment is self-similar in nature. This universal property allows us to find their fitting function and calculate the reduced (compressed dependence; the initial number of points is 1000, described by the number of frequency response modes is 14). The initial curve is invariant with respect to its transformed analogue after fivefold compression. For two different types of data obtained in open circuit and in metal polarization with microcurrent, a common fitting platform can be obtained related to its parameters. There are various methods of detrending: i.e., obtaining a trend from the original non-trending noise. The simplest way to obtain a trend that does not give computational errors is obtained from the formula for numerical integration using the trapezoidal method. It is this trend, obtained from the original trendless sequence without additional data processing errors, that makes sense to define as a clear trend. The approximation parameters can be used to compare various random processes, including those caused by reactions on the metal surface with changes in its microrelief during oxidation-reduction processes.