Insight into the pitting corrosion behavior of aluminum alloys

Abstract

On the basis of the literature data and the current results, a mechanism for the pitting corrosion of Al alloys is proposed. An assumption is made that the transport of Cl − ions through defects in the passive film of aluminum and aluminum alloys is not a rate determining step in pitting. The pit development is controlled by the solubility of the oxidized alloying elements in acid solutions. A very good correlation was found between the pitting potential and the oxidized alloying elements for metastable AlCr, AlZr, AlW and AlZn alloys.