Crevice Corrosion Behavior of 2A12 Aluminum Alloy and Ti Alloy Lap Joint in Salt Spray Environment

The crevice corrosion behavior of 2A12 aluminum alloy lap joint in neutral salt spray was studied by means of corrosion morphology observation, corrosion product analysis, polarization curve and electrochemical impedance spectroscopy testing. The results showed that compared with exposed zone of 2A12 aluminum alloy and Ti alloy lap joint, the corrosion in crevice zone was more serious, and there was an obvious dividing line between crevice zone and exposed zone; For exposed zone of 2A12 aluminum alloy lap joint, there was no obvious corrosion phenomenon in the early stage of corrosion, and pitting corrosion occurred after 12 hours of corrosion; For crevice zone of 2A12 aluminum alloy lap joint, with the extension of corrosion time, the metastable pitting corrosion gradually developed into steady pitting corrosion, corrosion intensified and pitting pits were formed.