Study on interaction between macrocell and microcell in the early corrosion process of reinforcing steel in concrete

An array electrode technique was developed as a novel electrochemical method for studying the interaction between macrocell and microcell in the early corrosion process of reinforcing steel in cement mortar.The corrosion potential and galvanic current of macrocell corrosion of the reinforcing steel in cement mortar were imaged by the array electrode technique during the corrosion initiation and propagation.It was certified that the corrosion macrocell current is closely related with the difference of corrosion potential between the anodic and cathodic areas.The corrosion macrocell and microcell always exist during the corrosion process.The interaction of corrosion macrocell and corrosion microcell of steel in concrete was directly sensed by the array electrode for the first time,and was discussed in terms of corrosion electrochemistry.