Comparative study of the corrosion behavior of zinc coatings deposited on low carbon steel substrates

The corrosion behavior of zinc pack coatings was examined with X-ray diffraction (XRD) and scanning electron microscopy (SEM) and it was compared with the performance of the zinc coatings formed with hot dipping. The examined samples were exposed in a salt spray chamber (SSC) for different periods of time starting from 24 h up to ten days. This investigation showed that the main corrosion products were Zn- and Fe-hydrated chlorides and oxides, while a stress corrosion mechanism controlled the pack corrosion. By contrast, the hot-dipped coatings are uniformly corroded, while pitting corrosion and internal oxidation are also possible. Copyright (C) 2006 John Wiley & Sons, Ltd.