Journal of Applied Electrochemistry

, Volume 44, Issue 10, pp 1093–1105 | Cite as

Influence of buffering on the spontaneous deposition of cerium conversion coatings for corrosion protection of AA2024-T3 aluminum alloy

  • Stephan V. Kozhukharov
  • Olaia F. Acuña
  • Maria. S. Machkova
  • Vladimir S. Kozhukharov
Research Article
Part of the following topical collections:
  1. Corrosion


Cerium-based conversion coatings were spontaneously deposited on AA2024-T3 alloy at 60 °C using buffered and non-buffered CeCl3 solutions in the presence of H2O2. Malonic acid or amino-acetic acid (glycine) was used as buffering additives. The deposition process and the properties of the coatings obtained were followed by linear voltammetry and electrochemical impedance spectroscopy. The surface morphology was studied by scanning electron microscopy. It was found that buffering complicates the conversion process and hampers the deposition rate. The coatings deposited using buffered baths had lower barrier ability and corrosion durability in 3.5 % NaCl corrosive medium compared to those deposited in the absence of buffers.


AA2024-T3 alloy Cerium conversion coatings Corrosion protection Electrochemical tests Surface morphology 



The authors gratefully acknowledge the financial support of project BG 051PO001-3.3.06-0038. We are thankful to Assoc. Prof. Dr. Eng. I. Nenov for the valuable information provided and for his assistance with the data interpretation. Dr. Gustavo Pelaez Lourido is acknowledged for the opportunity for international collaboration activities.


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Copyright information

© European Union 2014

Authors and Affiliations

  • Stephan V. Kozhukharov
    • 1
  • Olaia F. Acuña
    • 2
  • Maria. S. Machkova
    • 1
  • Vladimir S. Kozhukharov
    • 1
  1. 1.University of Chemical Technology and MetallurgySofiaBulgaria
  2. 2.University of VigoVigoSpain

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