Nanoparticle incorporation in plasma-electrolytic oxidation

Abstract

One remaining problem of thicker PEO based topcoats on light metal substrates is the enhanced porosity with increasing layer thickness. While modern deposition techniques such as pulsed anodisation counteract this phenomenon, a simple current signal based approach cannot completely eliminate this problem. In the process described in this paper the pulse anodised PEO layers are modified by the incorporation of functional nanoparticles and the effects of such embedded nanoparticles on the resulting microstructure of the layer are studied. The examination of the layer properties was performed using scanning electron microscopy, electrochemical techniques and X-ray diffraction methods. The dependency of corrosion resistance on the presence of nanoparticles in the layer as well as the alloy composition of the substrate and the applied current signal is shown.

Keywords:

• Plasma-electrolytic oxidation
• Nanoparticles
• Aluminium
• Pulse anodisation

Acknowledgements

The X-ray diffraction measurements were performed by Werner Artner at the X-ray Center of the Vienna University of Technology. This paper is based on a presentation given at IMFAir 2015 conference, Dudley, 9–10 June, 2015.