Sealing of tartaric sulfuric (TSA) anodized AA2024 with nanostructured LDH layers

• Autor(a) principal: Kuznetsov, B.
• Data de Publicação: 2016
• Outros Autores: Serdechnova, M., Tedim, J., Starykevich, M., Kallip, S., Oliveira, M. P., Hack, T., Nixon, S., Ferreira, M. G. S., Zheludkevich, M. L.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Texto Completo: http://hdl.handle.net/10773/20113
• topic: ACTIVE CORROSION PROTECTION; DOUBLE HYDROXIDE FILM; T3 ALUMINUM-ALLOY; SOL-GEL COATINGS; ORGANIC COATINGS; BEHAVIOR; ACID; INHIBITION; NANOCONTAINERS; HYDROTALCITE

In this work, a functional sealing of a TSA anodic layer on AA2024 is suggested based upon the formation of inhibitor-containing Zn-Al layered double hydroxides (LDH). The LDH structures are formed in the pores of the anodic layer and on top of it as a result of hydrothermal treatment in a Zn2+-containing bath as shown by the structure, morphology and composition analysis. The resulting LDHs were loaded with a well-known corrosion inhibitor (vanadate). Electrochemical impedance spectroscopy, salt spray tests and scanning vibrating electrode techniques have shown a remarkable improvement in corrosion resistance of the LDH-modified sample in comparison with conventional hot-water sealing. The vanadate-loaded LDHs rendered a significant long-term active protection for the covered aluminum alloy substrate.