GI coatings are covered by a very thin aluminum layer
that precipitates after wiping. Anisotropic growing of zinc
crystals during solidification induces a strong basal texture
in GI coatings. Skin-pass induced changes in GI coating
surface chemistry, crystallography and reactivity have been
assessed. Local coating analyses have been performed (XPS,
TOF-SIMS) in order to describe local effects of roughness
indentation during skin-pass on coating characteristics. A laboratory bi-crushing device supported by XRD and EBSD
has been used to analyze the aluminum oxide behaviour
during deformation and ageing. Reactivity of such surfaces
has been tested using fatty acids.