The influence of cerium ion concentrations on the characteristics of hybrid films obtained on AA2024‐T3 aluminum alloy

Abstract

International audienceThis work aimed to study the corrosion behavior of AA2024-T3 aluminum alloy substrates pre-treated with 3 glicidoxypropyltrimethoxysilane (GPTMS) silane layers doped with different cerium ion concentrations. The withdrawal speed of substrates from the sol was 20 cm * min-1. The hybrid films were obtained by dip-coating process and analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy, Rutherford scattering spectroscopy (RBS), salt spray test, and electrochemical analyses. The correlation among the results obtained from different analyses was very good and indicated that the addition of Ce ion in the hybrid coating contributed to the corrosion resistance; however, for the high Ce ion concentration, the barrier effect of the hybrid films was deteriorated. The results obtained by RBS showed that the concentration of Ce ion in the hybrid film increased linearly with the concentration of Ce ion in the sol. Moreover, it was verified that, for the nominal concentration of 0.05 M Ce ion in the sol, the Ce atomic fraction increased in the hybrid film, while the Si atomic fraction reduced, indicating the possible modification on the silane network due to the incorporation of Ce ions

New Sol-gel Formulations to Increase the Barrier Effect of a Protective Coating Against the Corrosion and Wear of Galvanized Steel

“…The aim of this work is to coat galvanized steel with a hybrid film obtained by a dip-coating process from a sol consisting of alkoxide precursors, 3 -(trimethoxysilylpropyl) methacrylate (TMSM) and tetraethoxysilane (TEOS), with nitrate cerium in a concentration of 0.01 M 20 . The influence of the concentrations (0, 20, 40 and 60 g.L -1 ) of polyethylene glycol (PEG 1500) plasticizer added in the sol formulation was evaluated.…”

“…The main steps are the hydrolysis and condensation of metal alkoxides to obtain metaloxane chains. These chains generate sols that can be used to coat numerous metallic and alloy substrates to protecting them against corrosion [20][21][22][23][24][25][26] .…”

Characterization of Siloxane-poly(methyl methacrylate) Hybrid Films Obtained on a Tinplate Substrate Modified by the Addition of Organic and Inorganic Acids

“…In order to improve corrosion resistance of the metallic substracts are applied protective coatings as based in the silanes [6][7][8] . Pretreatments based on siloxane-PMMA have demonstrated promising results, attracting industrial attention.…”

Corrosion Mechanism Suggested Based on Electrochemical Analysis and SVET for Uncoated Tinplate and Post Coated With a Hybrid Film

“…Reactions were conducted in TEOS/TMSM/alcohol/water solutions in the molar ratio 1/0.125/10.327/7.875 M, respectively, with the addition of 0.01 M cerium nitrate 26 . After 24 hours of hydrolysis, there were no significant differences in the pH values, which were in the range of pH 4.6 to pH 4.75.…”