Electrically conductive graphene nanoplatelet/boron carbide composites with high hardness and toughness

B4C composites containing 1-4 vol.% graphene nanoplatelet (GNP) were fabricated aiming at obtaining electrically conductive B4C composites with high toughness. The electrical conductivity of B4C composite was enhanced remarkably with the addition of only 2 vol.% GNPs. Besides, all the GNP/B4C composites maintained high Vickers hardness. The fracture toughness kept increasing with the increase of GNPs volume fraction and a high value of 5.26 MPa.m(1/2) was obtained in GNP/B4C composite with 4 vol.% GNPs. The main toughening mechanisms include GNPs pull-out, crack deflection and crack bridging. (C) 2015 Elsevier Ltd. All rights reserved.