DYNAMICS of SALT FILM BEHAVIOR DURING ELECTRODISSOLUTION of Fe, Ni AND ALLOYS in CONCENTRATED CHLORIDE SOLUTIONS

摘要

Oscillatory behavior observed during high rate electrodissolution of Fe, Ni and FeNi alloys in concentrated chloride solutions has been investigated. The observed potential oscillations have been ascribed to the cyclic growth and breakdown of a porous anodic film. The chaotic nature of these potential oscillations has been characterized by power spectral densities, phase portraits, Poincare sections, correlation dimensions and largest Lyapunov exponents. These results along with direct examination of the disk surface during and after the electrodissolution experiments suggest that the chaotic oscillations are related to the instability of the anodic salt film leading to localized corrosion processes.