Corrosion product force measurements in the study of exfoliation and stress corrosion cracking in high strength aluminium alloys

Exfoliation corrosion was assessed in three high strength aluminium alloys by measuring the force generated by voluminous corrosion products and their stress corrosion behaviour was studied in tests on double cantilever specimens. There was an inverse linear relationship between the corrosion product forces and the K-ISCC values for stress corrosion cracking in these materials, providing further evidence for a common corrosion mechanism. Exfoliation and SCC were both dependent on the rate of intergranular corrosion, which is controlled in these alloys by the grain boundary precipitates and the resistance to both forms of corrosion was improved in alloys with an over-aged heat treatment condition. (C) 2003 Elsevier Ltd. All rights reserved.