Densification of high-strength B4C–TiB2 composites fabricated by pulsed electric current sintering of TiC–B mixture

Abstract

The densification and mechanical properties of B4C–TiB2 composites fabricated by reactive pulsed electric current sintering from a mixture of TiC and amorphous B powders were investigated. The excess of B was essential to remove the carbon produced by the reaction. The degassing process at 1900°C before applying a 50MPa external pressure greatly improved the densification of the composites. The B4C–41vol% TiB2 composite obtained at the optimum condition had a high 3-point bending strength of 891MPa, a Vickers hardness of 28GPa and a fracture toughness of 4.4MPam1/2, respectively.