Abstract
Different 30Si3N4/70vol.%SiC composites, without and with additions of titanium (Ti), titanium diboride (TiB2) and cubic boron nitride (cBN), were obtained by High Pressure - High Temperature (HPHT) sintering. Density, Young’s modulus, hardness, fracture toughness and coefficient of friction were measured. Microstructural (SEM) investigations were also conducted for selected samples. Materials obtained from 30Si3N4/70vol.%SiC submicro powders with the addition of 30 vol.% cBN micro powder were characterized by the best combination of Young’s modulus, hardness, fracture toughness and coefficient of friction. The microstructures of investigated samples were compact and dense, with the ingredients uniformly distributed in the volume of composite. Such properties predispose 30Si3N4/70vol.%SiC+ 30vol.%cBN composites to various advanced engineering applications.