Effect of water rinsing temperature for steel substrate on corrosion behavior of hot-dip aluminizing coatings

摘要

The relationship between the morphology and protective action of hot-dip aluminizing coatings on Q235 steel have been investigated by SEM, EDS and EIS in 3.5 wt% NaCl aqueous solution. The results indicated that the anti-corrosion performance of the hot-dip aluminizing coatings using steel substrate rinsed by the distilled water at 25°C was higher than that at 80°C. The evolution of localized corrosion from pitting to exfoliation corrosion has been found on the aluminum-coating surface during immersion, and corresponding equivalent circuit models were proposed to fit the EIS data in the initiation and propagation stages of corrosion process.