Corrosion comparison of galvanized steel and aluminum in aqueous environments

Abstract

A corrosion test of galvanized steel and aluminum was carried out in three different aqueous environments, 5% NaCl solution, sea water and rain water, using the immersion test technique. Corrosion rate was measured in mdd (mg/dm2/day) units. Aluminum was considered as a possible alternative to galvanized steel. The corrosion characteristics of the corroded samples were investigated by XRD, XRF and SEM analysis. Although various results were obtained all through this study, aluminum was seen as more corrosion resistant than galvanized steel in the conditions tested in all three aqueous environments. Galvanized steel might be more corrosion resistant than aluminum in long term exposure in rain water. Without taking into account cost comparisons, aluminum can be used as a substitute for galvanized steel in industrial structures (roofing sheets) and water distribution systems.