IN-SITU RAMAN-STUDY OF THE CORROSION OF ZINC-COATED STEEL IN THE PRESENCE OF CHLORIDE .1. CHARACTERIZATION AND STABILITY OF ZINC CORROSION PRODUCTS

The different corrosion products formed on zinc specimens (pure or industrially electrodeposited) during exposure to solutions containing two concentrations of chloride were identified by Raman spectroscopy; the crystallographic nature of these products was checked by x-ray diffraction and their morphology was described by scanning electron microscopy. The conditions of formation of hydroxycarbonates and hydroxychlorides were described, as well as the influence of pH on the growth of the different modifications of Zn(OH)(2). The cathodic or anodic nature of the mechanisms leading to the stabilization of the different products was particularly emphasized.