Improvement of the corrosion resistance of electrodeposited Zn-Fe by sol-gel conversion films

Journal of Electrochemical Science and Engineering

Catherine Savall¹  Juan Creus¹  Yoann Paint²  Céline Arrighi³  Marjorie Olivier⁴ 

[1] Laboratoire des Sciences de l’Ingénieur pour l’Environnement (LaSIE) UMR CNRS 7356 – La Rochelle University, Av. Michel Crépeau, 17042 La Rochelle, France;Materia Nova ASBL, Avenue Copernic 1, 7000 Mons, Belgium;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;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;

关键词: Electrochemical impedance spectroscopy;    zinc alloys;    aqueous based solution;   

DOI  :  10.5599/jese.1282

来源: DOAJ

【 摘 要 】

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.

【 授权许可】

Unknown