Corrosion protection of AA2024-T3 by {LDH} conversion films. Analysis of {SVET} results
By Tedim, J.; Bastos, A. C.; Kallip, S.; Zheludkevich, M. L.; Ferreira, M. G. S.
Published in Electrochimica Acta
2016
Abstract
Abstract In this work the protective effect of layered double hydroxide (LDH) films directly grown on the surface of 2024-T3 aluminium alloy is investigated using electrochemical impedance spectroscopy (EIS) and the scanning vibrating electrode technique (SVET). The {SVET} results focused on the localised nature of the corrosion process and are in agreement with the global response measured by EIS. Furthermore, the evolution of active corrosion protection rendered by {LDH} films is surveyed at microscale for the first time for long immersion periods in NaCl solution and in the presence of induced defects. The quantitative information provided by {SVET} is discussed and a parameter to describe the degree of corrosion localisation is introduced based on {LDH} systems.