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Chromate and Chromate–Phosphate Conversion Coatings on Aluminium

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Abstract

Investigations of chromate and chromate–phosphate conversion coatings on aluminium using SIMS and AES techniques revealed that they are composed of hydrated chromium oxide/hydroxide and chromium phosphate respectively. These compositions are consistent with the electrochemical mechanism for conversion coating formation on aluminium. Enrichment of the outermost regions of the coatings with coating solution species suggests the gradual migration of these species under a concentration gradient towards the metal/coating interface where coating formation and growth consume such species.

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Author notes

  1. M. Oki

    Present address: Institute of Petroleum Studies, University of Port Harcourt, PMB 2 Choba Post Office, Port Harcourt, Rivers State, Nigeria

Authors and Affiliations

  1. School of Science and Technology, National Open University of Nigeria, Ahmadu Bello Way, Victoria Island, Lagos, Nigeria

    M. Oki, T. K. Oki & E. Charles

  2. Technical Department, Greenfield-Oaks Limited, London, M25 4HL, UK

    T. K. Oki

  3. Department of mechanical Engineering, Niger Delta University, Wilberforce Island, Bayelsa State, Nigeria

    E. Charles

Authors
  1. M. Oki
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  2. T. K. Oki
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  3. E. Charles
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Correspondence to M. Oki.

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Oki, M., Oki, T.K. & Charles, E. Chromate and Chromate–Phosphate Conversion Coatings on Aluminium. Arab J Sci Eng 37, 59–64 (2012). https://doi.org/10.1007/s13369-011-0157-2

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  • DOI: https://doi.org/10.1007/s13369-011-0157-2

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