Abstract
Abstract To clarify the mechanism of pitting corrosion of Al, the effect of a large amount of Zn (up to 2%) on Al pitting was studied in terms of pitting potential (Epit), repassivation potential (Erep), and pit nucleation transients. Epit in 0.5 M sodium chloride (NaCl) decreased with increased Zn content, and Erep was 50 mV to 60 mV below Epit, independent of Zn content. The shift of the anodic polarization curve in 6 M hydrochloric acid ([HCl] pit-like solution) was consistent with the change of Epit with Zn content. Analysis of passive current noise at the pA level in buffered solutions, with or without chloride (Cl−), showed noise caused by Cl− started at roughly the lowest potential where pitting occurred and had a similar potential dependence, irrespective of Zn content. Therefore, it was considered that pit nucleation had the same potential dependence, and possibly the same frequency, in Al-Zn alloys and pure Al and that the effect of Zn simply was to enhance dissolution kinetics in the local envi...
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
