The mechanical response of a commercial aluminum alloy, AA7085, was examined using slow strain rate testing in dry air and humid air at 70 °C. These tests and fractographic observations confirmed that the alloy suffered from hydrogen embrittlement when exposed to humid air. Crack initiation was studied in both environments to evaluate the effect of humidity on crack nucleation. Observations from both slow strain rate tests and constant displacement tests were compared. Specimens from slow strain rate testing were examined after fracture while constant displacement testing allowed periodic observations of the sample surface. Based on these observations, a mechanism for the crack initiation in humidity has been proposed for AA7085 that does not involve substantial contribution from anodic dissolution.
