Nanocharacterization of spark plasma sintered TiB2–SiC–graphene composites

Abstract

This investigation studies TiB 2 –SiC–graphene ceramics in terms of microstructure and mechanical properties. Spark plasma sintering (SPS) at 1800 °C was employed as manufacturing route, and the as-sintered composite was studied using high-resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), X-Ray diffractometry (XRD), and nano-indentation. The system was found to be unreactive, and all results dismissed the in-situ nucleation of B 4 C and TiC phases. Although TiO 2 and B 2 O 3 surface impurities were mainly reduced upon the incorporation of graphene nano-platelets (GNPs), the presence of SiO 2 in the final microstructure was confirmed by both XRD and HRTEM methods. The TiB 2 phase achieved a hardness of 35 GPa and a Young modulus of 539 GPa, which were roughly 45% and 25% higher than those measured for the SiC phase. • Microstructure and mechanical properties of TiB 2 –SiC–graphene composite was studied. • TEM, SEM, XPS, EDS, XRD, and nanoindentation tests were used for characterization. • Surface impurities of TiO 2 and B 2 O 3 were reduced by graphene nano-platelets.