Stress Corrosion Cracking of 7020 Aluminum Alloy

The stress corrosion cracking (SCC) caracteristics of 7020 aluminum alloy were studied by usibg the pre-cracked double cantilever beam (DCB) specimen.The results showed that the 7020 aluminum alloy was sensitive to SCC in solution containing Cl-,although the time of crack initiation was relatively long and the crack growth was relatively slow at the “Z-X” and “Z-Y” directions.The crack propagation speed was much faster when temperature increased and the cracks were horizontally extended.Some step-like discontinuous expansion and clustering phenomena were found on the surface.Results of SEM showed that the cracks were intergranular.