Study of the localized corrosion resistance of AA5083 aluminium alloy subjected to severe plastic deformation

In this work the localized corrosion behaviour of AA5083 aluminium alloy, subjected to severe plastic deformation (SPD) through the Equal Channel Angular Pressing technique (ECAP), useful to obtain an ultrafine microstructure, was studied. This process improves mechanical properties and modifies the microstructure of the alloy. With more details, the localized corrosion resistance of the AA5083 alloy subjected to thermal and cryogenic treatments and finally to ECAP was evaluated. Electrochemical characterization of this alloy was performed in aqueous solution 0.1 M of NaCl and pH 6.5, at room temperature, by means of cyclic potentiodynamic polarizations and potentiostatic polarizations for evaluating metastable pitting events. All tests were performed in deaerated conditions. The experimental results show that ECAP tends to increase AA5083 alloy localized corrosion susceptibility.