Corrosion and time dependent passivation of Al 5052 in the presence of H2O2

Batmanghelich, F ; Sharif University of Technology | 2016

392 Viewed
  1. Type of Document: Article
  2. DOI: 10.1007/s12540-016-5699-0
  3. Publisher: Korean Institute of Metals and Materials , 2016
  4. Abstract:
  5. Corrosion and time–dependent oxide film growth on AA5052 Aluminum alloy in 0.25M Na2SO4 solution containing H2O2 was studied using electrochemical impedance spectroscopy, potentiodynamic polarization, chronoamperometric and open circuit potential monitoring. It was found that sequential addition of H2O2 provokes passivation of AA5052 which ultimately thickens the oxide film and brings slower corrosion rates for AA5052. H2O2 facilitates kinetics of oxide film growth on AA 5052 at 25° and 60 °C which is indicative of formation of a thick barrier film that leads to an increment in the charge transfer resistance. Pitting incubation time increases by introduction of H2O2 accompanied by lower pitting and smoother surface morphologies. At short exposure (up to 8 h) to H2O2–containing solution, the inductive response at low frequencies predominantly determined the corrosion mechanism of AA5052. On the other hand, at prolonged exposure times (more than 24 h) to 0.25M Na2SO4+1vol% H2O2 solution, thicker oxide layers resulted in the mixed inductive–Warburg elements in the spectra
  6. Keywords:
  7. Alloys ; Corrosion ; Electrochemistry ; Metals ; Surface
  8. Source: Metals and Materials International ; Volume 22, Issue 4 , 2016 , Pages 609-620 ; 15989623 (ISSN)
  9. URL: https://link.springer.com/article/10.1007%2Fs12540-016-5699-0