Abstract
To investigate the effect of zinc content distribution on pit growth rate toward the direction of thickness, immersion test has been carried out in tap water containing 1ppm Cu++ on vacuum heated Al-Zn, Al-Mn-Zn and Al-Mg-Zn alloys. Pitting potential of aluminum alloys decreases with zinc content, whereas, no apparant difference is observed on pit growth rate between the materials having various profiles of zinc. This is attributed to the relatively uniform anodic dissolution of the alloys containing small amount of zinc in the solution within pit.
