Synthesis of TiB2-TiC-Ti3SiC2 composites by reactive hot pressing of B4C-SiC-Ti powder mixtures

Abstract

TiB2-TiC-Ti3SiC2 composites were reaction-sintered from B4C-xSiC-(3 + 2x)Ti (x = 0 to 1) powder mixtures using reactive hot pressing, and the phase relation of reaction products and sintering behavior were investigated. The reaction B4C + xSiC + (3 + 2x)Ti → 2TiB2 + (1 -x)TiC + xTi3SiC 2 proceeded fundamentally during hot pressing. Although the reaction demands no production of TiC phase at x = 1, TiC phase was formed due to the nonstoichiometry of TiC and Ti3SiC2 phases produced. The hot-pressed composites containing the layered compound Ti3SiC 2 had no preferential texture. Both TiB2 and TiC were first produced near 960°C during heating, and then Ti3SiC 2 near 1200°C. The product Ti3SiC2 contributed effectively to the densification of the composites above 1450°C. © 2008 The Japan Institute of Metals.