Corrosion characteristics of Al alloy/galvanized-steel Couple in NaCl solution

The corrosion characteristics of EN 6061-T6/ hot-galvanized IF steel jointed with tox punching and self-piercing rivets was compared using electrochemical impedance spectra, SEM, XPS, and EDS in sodium chloride solution. The results demonstrate that EN 6061-T6/hot-galvanized IF steel subject to tox punching presented more severe galvanic corrosion than the self-piercing rivet joint. The potential difference in the connected position can be promoted by the formation of a closed circuit corrosion current, leading to severe corrosion. Punching joint strained condition, such as extrusion and stretching, can potentially affect the corrosion performance of the partial region. The EIS of the stressed area showed obvious difference contrast to steel/aluminum sheets, especially the stretched region. The pitting corrosion of EN 6061-T6 appeared due to its electrochemical performance and the similarity between the potential difference in heterogeneity and pitting potential.