Advanced Materials

Passivation of metals by coating with polyaniline: Corrosion potential shift and morphological changes

Authors

  • Dr. Berhard Wessling

    Corresponding author
    1. Zipperling Kesseler & Co P.O. Box 1469, D-22904 Ahrensburg (FRG)
    • Zipperling Kesseler & Co P.O. Box 1469, D-22904 Ahrensburg (FRG)
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Abstract

Corrosion protection of metals can be obtained by coating them with polyaniline dispersions, resulting in a signifiecant and reproducible shift of the corrosion potential. Scanning electron micrograph indicate that the passivation is a multistep process, beginning with an etching stage in wh8ch grain boundaries become visible (see Figure). In the second step the metal surface is coated—non-electrochemically—with an oxide layer. The exact mechanism of formation of this layer remains to be explored.

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