Combustion synthesis and spark plasma sintering of MgAl2O4-graphene composites

Abstract

Abstract MgAl2O4-graphene composites have been fabricated from combustion synthesized ceramic-graphene powder mixtures by spark plasma sintering. The synthesis and dispersion of graphene was accomplished readily by a combustion reaction between Mg powders and CO2 gas. Compared with that of pure MgAl2O4, the relative density decreases from 100% to 95.1% and the average grain size decreases from 94 to 0.4\u202fµm for composites containing 2.5\u202fwt% graphene. The bending strength and fracture toughness of the as-prepared MgAl2O4-graphene composites increased by 34% (from 217 to 291\u202fMPa) and 32% (from 1.91 to 2.52\u202fMPa\u202fm1/2) at 0.5\u202fwt% graphene content. The prepared MgAl2O4-graphene composites may provide an alternative refractory material to withstand harsh environments.