Materials Research (Jun 2019)

Corrosion and Micro-abrasive Wear Behaviour of 2524-T3 Aluminium Alloy with PAni-NPs/PSS LbL Coating

  • Uriel Darhê Oudinot Dias Rangel,
  • Roger Borges,
  • Danilo Alves Oliveira,
  • Larissa Solano de Almeida,
  • Rogério Valentim Gelamo,
  • José Roberto Siqueira Júnior,
  • Luciana Sgarbi Rossino,
  • Jéferson Aparecido Moreto

DOI
https://doi.org/10.1590/1980-5373-mr-2018-0593
Journal volume & issue
Vol. 22, no. 3

Abstract

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In this paper, we present an alternative method to obtain thin films for coating protection on the surface of the AA2524-T3 Al-alloy by using the Layer-by-Layer (LbL) technique. The LbL films were fabricated by alternated immersion of the Al-alloy into a poly(styrene sulfonate) (PSS) and polyaniline nanoparticles (PAni-NPs) solutions, obtaining a PAni-NPs/PSS bilayer architecture. The LbL films were characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), electrochemical and micro-abrasive wear tests. The results show that the number of bilayers promotes shifts to less negative potentials, indicating an optimized system, in which the best performance was observed for a 15-bilayer PAni/PSS LbL film. The pitting potential (Epit) values shifted 130 mV (from -610 mV to -480 mV) in comparing a bare Al-alloy. The predominantly wear mechanism for AA2524-T3 with PAni-NPs/PSS bilayers was scratching whereas for the bare material there was an equivalence between scratching and rolling mechanisms. The results proved that the incorporation of PAni-NPS by the LbL method may be propitious as protective coating against corrosion in AA2524-T3 alloy.

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