The Postulated Mechanisms for Stress Corrosion Cracking of Aluminum Alloys

The stress corrosion cracking (SCC) of aluminum alloys is a well-documented phenomenon, but there is considerable disagreement in the scientific literature as to what mechanism causes it. This paper reviews the past 10 years of publications and describes the experimental methods and the proposed SCC mechanisms of about 90 selected papers. Different SCC mechanisms have been proposed for the different aluminum alloy systems: for example, anodic dissolution is generally favored in the 2xxx series aluminum alloys, while hydrogen-induced cracking is favored in the 7xxx series. However, considering the conflicting reports in the literature, it is still possible that other mechanisms are operational.