A Primary Study into Graphene/Polyether Ether Ketone (PEEK) Nanocomposite for Laser Sintering
Applied Surface Science
Elsevier for North-Holland Publishing
© 2017 The Authors. Published by Elsevier B.V.. Open Access funded by Engineering and Physical Sciences Research Council. Under a Creative Commons license: https://creativecommons.org/licenses/by/4.0/
This paper proposes two methods of preparation of graphene/PEEK powders for Laser Sintering (LS) and investigates their behaviour in relation to their microstructure, the powder bed process and their properties. Thin composite films were fabricated in an attempt to replicate the thin layer formation of the powder bed process. Both methods of composite powder preparation (wet and dry) led to enhanced mechanical performance of the composite films at 0.1 and 0.5% graphene nano-platelets (GNP) concentrations. The TEM images show that the GNP act as a nucleation point in crystallisation of PEEK, being at the centre of the spherulites. The hot stage microscopy revealed a 20 second delay in the onset of GNP/PEEK nanocomposite coalescence in comparison with plain PEEK. This is a very important observation for laser sintering, as it will influence the build strategy and specific parameters (e.g. time between layers deposition, multiple exposures). The excellent electrical conductivity properties of graphene were noticeable in the nanocomposite films at concentrations above 1 wt% GNP.
The authors would like to thank the UK Engineering and Physical Science Research Council for its funding (EPSRC grant no EP/L017318/1-Particle Shape and Flow behaviour in Laser Sintering: from modelling to experimental validation), 2D-Tech for providing the graphene and John Benson for his help with the Raman evaluation.
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.
Published online 28 September 2017