On the respective effect of the surface energy and micro-geometry in the cleaning ability of bare and coated steels

It is aimed in this paper to assess the respective effect of surface energy and topography in the cleaning kinetics of soiled surfaces. Different flat and engraved stainless steels are characterized using contact angle measurements, topographic analysis and cleaning kinetics in presence of surfactants. Two coatings are also distinguished: silicon oxide (hydrophilic) and polysiloxane (hydrophobic).Except for the engraved surfaces, the determining parameter for the cleaning ability is the polar component of the surface energy: the larger this component, the better the cleaning performance. We proposed a simple model following which favorable interactions take between polar sites and the heads of surfactant. However, for engraved surfaces, the cleaning kinetics is strongly modified by some impregnation phenomena.