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. (C) 2016 Elsevier Ltd. All rights reserved.
keywords
ALUMINUM-ALLOY 2024-T3; INHIBITION; AL; CHROMATE; COATINGS; METALS
subject category
Electrochemistry
authors
Tedim, J; Bastos, AC; Kallip, S; Zheludkevich, ML; Ferreira, MGS
our authors
António Alexandre Cunha Bastos
Assistant Researcher
João Tedim
Associate Professor
Mário Guerreiro Silva Ferreira
Retired Professor
Mikhail Zheludkevich
Invited Principal Researcher
Silvar Kallip
Assistant Researcheracknowledgements
This work was developed in the scope of the project CICECO-Aveiro Institute of Materials (Ref. FCT UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when applicable co-financed by FEDER under the PT2020 Partnership Agreement. JT and SK thank FCT for researcher grants IF/00347/2013 and IF/00856/2013, respectively. Authors also thank FCT (Portugal) for project CONVPROTECT - PTDC/CTM-MAT/1515/2012 and the European Commission for project H2020-MSCA-RISE-2014-645676-MULTISURF. Authors thank Dr. Eddy Domingues for the acquisition of SEM/EDS images.