Anisotropic mechanical and functional properties of graphene-based alumina matrix nanocomposites

Yasemin Çelik (1, 2) , Ali Çelik (2) , Emmanuel Flahaut (1) , Ender Suvaci (2)

1 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux
2 Department of Materials Science and Engineering

Graphene platelets (GPLs) containing Al2O3 nanocomposites, which exhibit anisotropic microstructure,have been prepared by spark plasma sintering (SPS), and effects of this anisotropy on mechanical, elec-trical and thermal properties of the nanocomposites have been investigated. 3 vol.% GPLs addition intomonolithic Al2O3caused fracture toughness (Kıc) to increase by 26.7% in the in-plane direction and todecrease by 17.2% in the through thickness direction. Kıcstarted to decrease in the in-plane direction andto increase in the through-thickness direction with further increase in the GPLs amount. The electricalconductivity of the nanocomposites exhibited a slight anisotropy with a lower resistivity in the in-planedirection. Oriented GPLs also led to a less resistive heat conduction path in the in-plane direction. ∼44% increase in the in-plane thermal conductivity was achieved at 600°C with 15 vol.% GPLs addition into themonolithic Al2O3and this resulted in ∼52% increase in the k in-plane/k through-thickness ratio

Mots clés: Graphene platelets/Al2O3 nanocomposites; Mechanical properties; Electrical conductivity; Thermal conductivity; Anisotropy

Domaines: Matériaux; Matériaux

Yasemin Çelik, Ali Çelik, Emmanuel Flahaut, Ender Suvaci. Anisotropic mechanical and functional properties of graphene-based alumina matrix nanocomposites. Journal of the European Ceramic Society, 2016, 36 (8), pp. 2075-2086. ⟨10.1016/j.jeurceramsoc.2016.02.032⟩. ⟨hal-01451008v2⟩