Fracture Toughness of Carbon-Graphene/Epoxy Hybrid Nanocomposites

Abstract

Plain strain fracture toughness (K IC ) of graphene-epoxy (G-Ep) and carbon-graphene-epoxy (C-G-Ep) hybrid nanocomposites have been evaluated using single-edge-notch bending (SENB) specimens. The effects of graphene concentrations on K IC have been examined. G-Ep nanocomposites were prepared using a combination of mechanical mixing, magnetic stirring, sonication and high shear mixing. The hybrid nanocomposites (C-G-Ep) were processed using manual layup techniques and vacuum assistance during curing process. The dispersion morphology and fracture surface of all specimens were evaluated using scanning electron microscopy(SEM) analysis. The results show significant improvement in fracture toughness of both G-Ep and C-G-Ep nanocomposites in comparison to neat epoxy and conventional carbon-epoxy composites. The SEM images show evidence of slight graphene agglomeration, but reasonably effective graphene dispersion is observed throughout epoxy matrix. The toughening mechanisms such as crack deflection, crack pinning, debonding, fiber bridging and pull-out are possibly contributed to enhancing fracture toughness in G-Ep and C-G-Ep nanocomposites.

Investigation of the mechanical, thermal, and anticorrosion properties of epoxy nanocomposite coatings: Effect of synthetic hardener and nanoporous graphene

“…The addition of nanoparticles such as graphene, graphene oxide, carbon nanotubes, and nanosilica could improve toughness and mechanical properties, thermal stability, and anticorrosion properties of ER . Carolan et al .…”

Elaboration of properties of graphene oxide reinforced epoxy nanocomposites

“…However, epoxy resins are generally brittle which restrict their applications. Hawkins et al [35,36] studied the fracture toughness and strain energy behavior of carbon-graphene/epoxy hybrid nanocomposites. GO-epoxy based nanocomposites also possess the flexural behavior.…”

Effects of Hybrid Graphene Oxide with Multiwalled Carbon Nanotubes and Nanoclay on the Mechanical Properties and Fire Resistance of Epoxy Nanocomposite

“…Many studies have been reported on hybrid filler technology in polymers, based on GO and MWCNT [13][14][15][16]. The results of this study open up many directions for further research on GO.…”

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