Cathodic polarization of commercially pure aluminium

摘要: Abstract Cathodic corrosion, particularly alkaline pitting and repassivation, of 1S aluminium has been investigated by potential-controlled methods in unbuffered chloride media. The results are mainly for de-aerated solutions; the influence dissolved oxygen stirring, which likely to be present a practical situation, also discussed. metal undergoes stable then uniform etching as applied potential is decreased below − 1.35 V(SCE). At potentials more positive than this threshold value, dissolution still occurs possibly near cathodic impurities on surface due local alkalinization resulting from hydrogen evolution; but, repassivates slowly sites covered up oxide film. polarization behaviour partially passive studied fast-scan measurements associated with evolution kinetics. measured current decays exponentially time during repassivation at constant potential. This explained terms model based film growth controlled dissolution.