Corrosion behavior and mechanism of 7050 high-strength aluminum alloy under stress

Electrochemical activity, corrosion evolution behavior and mechanism of 7050 high-strength aluminum (Al) alloy under stress and corrosion medium were investigated through in situ electrochemical tests and constant load tensile stress corrosion experiments. Electrochemical activity of 7050 Al alloy intensifies with elevated stress levels. Pitting corrosion mainly occurs after 2–48 h of corrosion of 7050 Al alloy under different stress levels, and pitting corrosion is more serious with increasing stress level. The generation of pitting corrosion is mainly concentrated in intermetallic compounds Al (Cu, Fe). Within the elastic regime, stress enhances electrochemical reactivity, which promotes corrosion process. The plastic stress effect leads to more finely distribution of large intermetallic compounds becoming, which accelerates anodic dissolution of α (Al) substrate. Corrosion reaction process is promoted further, which reduces corrosion resistance performance of the alloy.