DI-UMONS : Dépôt institutionnel de l’université de Mons

Recherche transversale
(titres de publication, de périodique et noms de colloque inclus)
2019-09-12 - Colloque/Présentation - communication orale - Anglais - page(s)

Prince Loïc , Rousseau Marie-Aude, Noirfalise Xavier, Bertolucci Coelho Leonardo , Poorteman Marc , Olivier Marie-Georges , "Comparative study on the effect of cerium, lanthanum and lithium salts corrosion inhibitors for the protection of AZ31 magnesium alloys" in Eurocorr 2019, Sevilla, Spain, 2019

  • Codes CREF : Corrosion des matériaux (DI2114)
  • Unités de recherche UMONS : Science des Matériaux (F502)
  • Instituts UMONS : Institut de Recherche en Science et Ingénierie des Matériaux (Matériaux)

Abstract(s) :

(Anglais) Magnesium alloys are the world’s lightest structural metals, with an extraordinary growth potential in view of the accelerating demands for light-weighting materials in portable devices and transportation (aerospace, automotive). However, this material class has poor corrosion resistance properties and, therefore, requires an efficient protective system. Furthermore, due to health issues concerning Cr VI - based anti-corrosion compounds, the mentioned sectors urge for the development of new environmentally friendly corrosion inhibitors. Fast, effective and irreversible passivation is an essential protection of magnesium alloys. Since a few years, lithium-salts gained increasing interest as a potential alternative for chromates for corrosion protection of aluminum alloys. In this paper, the authors present a comparative study of the active protective properties of cerium, lanthanum and lithium salts on AZ31 magnesium alloy, aiming at improving the understanding of the inhibition behavior for long immersion periods in an aqueous electrolyte. The influence of counter ions of the salt inhibitor has also been investigated. The morphology of the surface was studied using Scanning Electron Microscopy (SEM). The electrochemical activity of the inhibitors in sodium chloride solution was studied versus immersion time using Electrochemical Impedance Spectroscopy (EIS) and anodic and cathodic polarization curves. The composition of the film formed in the surface were analyzed using X-ray Photoelectron Spectroscopy (XPS). A protection mechanism is proposed.