Characterization of aluminium alloys in tetrahydrofuran media

Rest potential measurements and voltammetric scans at different rates (0.01-1 V min-1) have been carried out on aluminium alloys in a tetrahydrofuran (THF) environment. The solvent contained either chloride, perchlorate or trifluoromethane sulfonate ions. For the Al-Mg alloys in chloride environments, the voltammograms observed for low scan rates show electrode passivation with the formation of a magnesium salt layer. For Al-Li alloys, rest potential measurements indicate the selective dissolution of lithium. The maximum dissolution current is sensitive to the lithium content in the alloy and limited by the solubility of lithium chloride. In chloride environments, the passivity breakdown potential Eb and the protective potential Ep have similar values and do not depend on the type of alloy. In contrast, large differences between these potentials are observed in the presence of CF3SO3- ions. © 1989 Chapman and Hall Ltd.