Interaction between alternating current and cathodic protection over nano sized/structured surface metals

Serious cases of corrosion of metallic structures under both alternating current (ac) and cathodic protection (cp) have been reported. The objective of this research is to propose a mechanism by which ac affects the nano sized/structured surface films formed on metals under cp. A model will be proposed and experimentally validated, in order to relate the metal corrosiveness to its nano sized/structured surface, under the simultaneous effect of ac and cp. This study intends to show how observations made by the ac-Voltammetry can be used to obtain an insight into the nature and mechanism of electrode processes. Once reactions are identified, the intensity and morphology of the surface damage will be related to the amplitude and frequency of the sinusoidal perturbation. Analytical and kinetic studies will be combined with Atomic Force Microscopy (AFM), performed firstly ex-situ and later in the electrolytic cell while the ac-corrosion is simulated, in order to obtain the nano-surface characterization.