RT info:eu-repo/semantics/article
T1 Contributions of microelectrochemical scanning techniques for the efficient detection of localized corrosion processes at the cut edges of polymer-coated galvanized steel. D. Filotás, J. Izquierdo, B.M. Fernández-Pérez, L. Nagy, G. Nagy, R.M. Souto.
A1 Souto, Ricardo Manuel
A1 Filotás, Dániel
A1 Izquierdo Pérez, Javier
A1 Fernández Pérez, Bibiana María
A1 Nagy, Lívia
A1 Nagy, Géza
A2 Química
A2 Grupo de Electroquímica y Corrosión
Departamento de Química
Instituto de Materiales y Nanotecnología
AB Spatially resolved information on corrosion reactions operating at the cut edges of coatedmetals can be obtained using microelectrochemical scanning techniques using a suitable selection ofoperation modes and scanning probes. The scanning vibrating electrode technique (SVET) providescurrent density maps with a spatial resolution of the order of the dimensions of the sample, whichallows the temporal evolution of the corrosion reactions to be followed over time. This leads to theidentification and localization of cathodic and anodic sites, although the technique lacks chemicalspecificity for the unequivocal identification of the reactive species. The application of scanningelectrochemical microscopy (SECM) was previously limited to image cathodic reaction sites, eitherdue to oxygen consumption in the amperometric operation or by the alkalinisation of the electrolytein potentiometric operation. However, it is shown that anodic sites can be effectively monitoredusing an ion-selective microelectrode (ISME) as a probe. The ISME probes detected differences inthe local concentrations of Zn2+ and OH− ions from the cut edges of a complete coil coating systemcompared to the same system after the polymeric layers were removed. In this way, it has been shownthat the inhibitor loading in the polymer layers effectively contributes to reducing the corrosionrates at the cut edge, thus helping to extend the useful life of the sacrificial galvanized layer bondeddirectly to the steel matrix. Additionally, these two probe configurations can be integrated into amulti-electrode tip for potentiometric operation to simultaneously monitor localized changes in pHvalues and metal ion dissolution in a single scan. Spatial and temporal distributions were furtherinvestigated using different rastering procedures, and the potential of constructing pseudomaps for2D-imaging is described.
YR 2022
FD 2022
LK http://riull.ull.es/xmlui/handle/915/26909
UL http://riull.ull.es/xmlui/handle/915/26909
LA en
DS Repositorio institucional de la Universidad de La Laguna
RD 19-may-2024