Corrosion inhibition of aluminium alloy AA6063-T5 by vanadates: Local surface chemical events elucidated by confocal Raman micro-spectroscopy

Kharitonov D. S., Sommertune J., Ornek C., Ryl J., Kurilo I. I., Claesson P. M., ...Daha Fazla

CORROSION SCIENCE, cilt.148, ss.237-250, 2019 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 148
  • Basım Tarihi: 2019
  • Doi Numarası: 10.1016/j.corsci.2018.12.011
  • Dergi Adı: CORROSION SCIENCE
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.237-250
  • Anahtar Kelimeler: Aluminium, Alloy, Raman spectroscopy, SEM, XPS, Vanadate inhibitor, OXIDE THIN-FILMS, IN-SITU, AQUEOUS VANADATE, GALVANIC CORROSION, AL-ALLOYS, VANADIUM, OXIDATION, 2024-T3, MECHANISMS, PROTECTION
  • İstanbul Teknik Üniversitesi Adresli: Hayır

Özet

Chemical interactions between aqueous vanadium species and aluminium alloy AA6063-T5 were investigated in vanadate-containing NaCl solutions. Confocal Raman and X-ray photoelectron spectroscopy experiments were utilised to gain insight into the mechanism of corrosion inhibition by vanadates. A greenish-grey coloured surface layer, consisting of V+4 and V+5 polymerized species, was seen to form on the alloy surface, especially on top of cathodic micrometre-sized IMPs, whereby suppressing oxygen reduction kinetics. The results suggest a two-step mechanism of corrosion inhibition in which V+5 species are first reduced to V+4 or V+3 species above cathodic IMPs, and then oxidized to mixed-valence V+5/V+4 polymerized compounds.