Microstructural and mechanical characterization of SiC-submicron TiB2 composites

The aim of this work is to characterize ceramic composites SiC-TiB2. After preparation of dense composites alpha SiC-TiB2 (5, 10 and 15 vol% TiB2) by reactive pressureless sintering, the materials have been characterized by their microstructure and their mechanical properties. The dispersion of TiB2 particles is quite homogeneous, observed both by optical and scanning electron microscopies. Image analysis has revealed a majority of submicronic particles. Atomic force and transmission electron microscopies have shown the presence of nanometric TiB2 particles. Concerning mechanical properties, toughness increases with the TiB2 content, whereas hardness decreases when the TiB2 content increases. (C) 1999 Elsevier Science Limited. All rights reserved.