Influence of pre-treatment on zirconium based conversion coating on AA2024

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Abstract

A comparison of the influence of two alloy pre-treatments and temperature treatments on the formation and composition of zirconium based conversion coating on the AA2024 alloy has been performed. The investigation employed mass changes, atomic force microscopy (AFM), XRD dispersive spectroscopy (EDX), infrared spectroscopy (IR) and electrochemical tests by open circuit potential (OCP) measurements. Pre-treatment using only alkaline etching is called alkaline pre-treatment. When alkaline etching is followed by de-oxidization in a phosphoric acid solution the process is called acidic pre-treatment. Conversion coatings were formed in Pragokor BL. IR analysis revealed the formation of a phosphate on the alloy surface. EDX analysis showed Mg dissolution. The Zr content increased with the temperature of the conversion coating formation. Both pre-treatment methods provided a phosphate layer on the alloy surface.

References

  • Aghazadeh M, Malek Barmi AA, Hosseinifard M (2012) Materials Letters: 28-31.

  • Boag A, Hughes AE, Wilson, NC, Torpy A, MacRae CM, Glenn AM, Muster TH (2009) Corrosion Science 51: 1565-1568.

  • Farmer VC (1974) The Infrared Spectra of Minerals. Mineralogical Society London.

  • Guo Y, Frankel GS (2012) Surface & Coatings Technology: 3895-3902.

  • Chen GS, Gao M, and Wei RP (1996) Corrosion 52: 8-15.

  • Kendig MW, Buchheit RG (2003) Corrosion 59: 379-400.

  • Nyquist RA, Kagel RO (1971) Infrared Spectra of Inorganic Compounds. Academic Press New York and London.

  • Qi J (1), Nemcová A, Walton RJ, Zhou X, Skeldon P, Thompson GE (2016) Thin Solid Films: 270-278.

  • Qi J (2), Hashimoto T, Walton RJ, Zhou X, Skeldon P, Thompson GE (2016) J. Electrochemical Society: C25-C35.

Acta Chimica Slovaca

The Journal of Slovak University of Technology in Bratislava

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