Original scientific paper
https://doi.org/10.5599/jese.1282
Improvement of the corrosion resistance of electrodeposited Zn-Fe by sol-gel conversion films
Céline Arrighi
; University of Mons-UMONS, Faculty of Engineering, Materials Science Department, Place du Parc, 20, 7000 Mons, Belgium and Laboratoire des Sciences de l’Ingénieur pour l’Environnement (LaSIE) UMR CNRS 7356 – La Rochelle University, Av. Michel Crépeau, 17042 La Rochelle, France
Yoann Paint
; Materia Nova ASBL, Avenue Copernic 1, 7000 Mons, Belgium
Catherine Savall
; Laboratoire des Sciences de l’Ingénieur pour l’Environnement (LaSIE) UMR CNRS 7356 – La Rochelle University, Av. Michel Crépeau, 17042 La Rochelle, France
Juan Creus
; Laboratoire des Sciences de l’Ingénieur pour l’Environnement (LaSIE) UMR CNRS 7356 – La Rochelle University, Av. Michel Crépeau, 17042 La Rochelle, France
Marjorie Olivier
orcid.org/0000-0001-7771-7454
; University of Mons-UMONS, Faculty of Engineering, Materials Science Department, Place du Parc, 20, 7000 Mons, Belgium and Materia Nova ASBL, Avenue Copernic 1, 7000 Mons, Belgium
Abstract
An aqueous hybrid inorganic/organic sol-gel solution composed of tetraethylorthosilicate (TEOS), methyltriethoxysilane (MTES) and (3-glycidyloxypropyl)trimethoxysilane (GPTMS) was applied on ZnFe (14 wt.% Fe) electrodeposited on steel as a sacrificial layer. Two precursor contents were studied: 10 (SG10) and 30 % (SG30). First, the morphology and thickness of the films were assessed by Scanning Electron Microscopy (SEM) observations. They revealed the presence of micro-cracks in the films without alkaline surface preparation due to the pyramidal shape of the ZnFe deposit. Then, the corrosion resistance of the systems was determined by Electrochemical Impedance Spectroscopy (EIS) and Neutral Salt Spray (NSS) test. All results indicated an improvement in the corrosion resistance thanks to the presence of the SG films. However, the protection provided by the SG10 film did not permit to durably protect the ZnFe deposit. The combination of surface preparation and a SG30 film provided promising protection to the ZnFe deposit with an increase of the low-frequency modulus and a delay in corrosion product appearance during the NSS test.
Keywords
Electrochemical impedance spectroscopy; zinc alloys; aqueous based solution
Hrčak ID:
283677
URI
Publication date:
18.9.2022.
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