Combined Elemental Synthesis of Boron and Silicon Carbides

Combined synthesis from powders of elements B, C, and Si at 1400, 1500, and 1650°C is used to prepare heterophase powders in the system SiC–B 4 C containing 80, 57, and 30 (mol.%) boron carbide. Powders containing only SiC and B 4 C phases are prepared at 1550°C from a mixture with 5% excess silicon given vibration grinding for 60 h. The powder has a unimodal particle size distribution and d 50 = 3.5 μm with a volume concentration of 12% submicron particles.