Microstructures and properties of large bulk solidified TiC–TiB 2 composites prepared by combustion synthesis under high gravity

Abstract

Large bulk solidified TiC–TiB2 composites with full density were prepared by combustion synthesis in a high-gravity field. The materials presented unique solidification microstructures in which a number of fine TiB2 platelets were embedded in TiC matrix. The hardness, flexural strength and fracture toughness of the materials were 28.5 GPa, 750 ± 25 MPa and 6.2 ± 0.5 MPa m1/2, respectively. The materials’ high hardness resulted from the absence of intermediate borides and the achievement of stoichiometric TiC phases due to rapid solidification.