Effect of Ce(III) and Ce(IV) ions on the structure and active protection of PMMA-silica coatings on AA7075 alloy

• DOI: 10.1016/j.corsci.2021.109581
• Publication Date: 2021-05-26T01:39:43Z
• Authors: A. Trentin; S.V. Harb; M.C. Uvida; K. Marcoen; S.H. Pulcinelli; C.V. Santilli; H. Terryn; T. Hauffman; P. Hammer
• Keywords: EIS; Intermetallics; 669; Aluminium alloy; aluminium alloy; Organic coatings; 02 engineering and technology; 0210 nano-technology; SIMS; inhibition; Inhibition

Abstract This work investigates the effect of Ce(III) and Ce(IV) additives on the structure and anti-corrosion properties of poly(methyl methacrylate) (PMMA)-silica coatings on AA7075 aluminium alloy. The results revealed that intermediate Ce(IV) loadings (500 and 1000 ppm) result in a dense hybrid network with a less defective polymeric phase, extending the service time of AA7075 up to 835 days in 3.5% NaCl. Although both additives provide long-term protection, the self-healing ability was observed only for Ce(IV) addition, favoured by the formation of oxides/hydroxides at pH∼3. These properties make the 4 μm-thick PMMA-silica-Ce(IV) coatings very interesting for chromium-free protection technologies.