CHROMATOGRAPHIC STUDIES OF CORROSION SITES IN METALLIC MATERIALS

Many types of corrosion phenomena are controlled by the ionic composit ion of a small volume of solution at the surface. Localized corrosion and atmospheric corrosion are two examples in which < 1 mul of solutio n can cause dramatic damage. Ion chromatographic (IC) techniques have been used to analyze these solutions in order to gain a better underst anding of the mechanisms which govern them. Two examples are presented . The presence of minor alloying elements at localized corrosion sites in two aluminum alloys has been demonstrated, indicating non-stoichio metric dissolution of the alloy during localized corrosion. In additio n, IC analysis allowed the determination of the species responsible fo r the atmospheric corrosion failure of electrical connectors, includin g their likely origin.