On the use of Ti Si eutectic alloy as a novel sintering aid for B4C TiB2SiC ceramic composites

24Ti-76Si (wt.%) eutectic alloy as a novel sintering aid for hot-pressing of B4C-based ceramic composites was proposed in this paper. B4C-TiB2-SiC ternary ceramic composites were fabricated by hot-pressing at 1850 degrees C via in-situ reaction of B4C and Ti-Si eutectic alloy. The results indicated that the addition of Ti-Si eutectic alloy significantly increase the density and enhanced the mechanical properties of B4C-based composites. The Vickers hardness, flexural strength, fracture toughness and compressive strength were 28.4 +/- 1.1 GPa, 582.3 +/- 45.5 MPa, 6.3 +/- 0.4 MPa m(1/2), and 4109.3 +/- 209.6 MPa, respectively, for the composite prepared with B4C-30 wt.% Ti-Si. These values were much higher than those of nominally pure B4C ceramic prepared by the same processing condition. The improved mechanical properties were attributed to the well-dispersed fine intergranular/intragranular TiB2 and SiC phases in the B4C matrix.