In this work, the corrosion behaviour of pure Al and its three alloys (Al-Cu-Mg, Al-
Mg, and Al-Zn-Mg) was studied in aerated and deaerated 1x10-3 NaOH
solutions to show the role of dissolved oxygen gas and its reduction at cathode. Also the
aim of this study was to obtain the corrosion parameters such as the corrosion potential
(Ecorr), corrosion current density (icorr), cathodic and anodic Tafel slopes (b), and
polarization resistance (Rp) besides the thermodynamic and kinetic functions were also
calculated (ÄG, ÄS, and ÄH) and (Ea and log A) to comparison these values in the
presence and absence of the oxygen.
From the general results for this study can be seen that the polarization resistances for
pure Al and its alloys were higher in deaerated solutions and the values of (ÄG) were
less spontaneous in deaerated solution, also the activation energy (energy barrier) was
higher in deaerated solution.