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In this work, the state-space diagrams, Lyapunov exponents and correlation dimension are obtained to characterize the corrosion process of an aluminum sample immersed in a solution of distilled water to 0.5, 1.5 and 3% NaCl. The stochastic analysis of the system is made from data sets obtained from Michelson interferometric patterns recorded during the optical monitoring of the corrosion process, which are digitally processed and converted into time series associated with the response of the optical pattern obtained. Moreover, the technique of spectral analysis (FFT) and calculation of the Hurst exponent (H) are used to establish a relationship between frequency components and morphology of corrosion in an entirely qualitative and where only distinguishes corrosion process.

A brief investigation is presented in an electrochemical corrosion cell consisting of 99.5% aluminum sample immersed in 3% NaCl and hydrocarbon-chloride solution emulsion, which reaction processes were optically monitored using Michelson interferometry. An image processing method applied on obtained interferograms allowed to calculate oxide corrosion layer thickness formed over the metal surface. Additionally a theoretical model consisting of a two bi-dimensional difference equation system is proposed, in order to explain evolution of optical interference pattern maxima observed as a function of time for corrosion process, and also to establish a growth-competition model for the maxima fringes evolution and consequently for the oxide layer and corrosion system dynamics. Bifurcation diagrams showing equation system solution regions were additionally obtained based on the nonlinear dynamic behavior of corrosion processes showing chaotic dynamics.