Mechanical Properties of Si<sub>3</sub>N<sub>4</sub>-SiC Composites Sintered by HPHT Method

Three types: micro-, submicro- and nano-structured Si3N4-SiC composites have been obtained by High Pressure-High Temperature (HPHT) sintering. Density, Young modulus, hardness and fracture toughness have been measured. Composites obtained from sub-micron powders are characterized by better mechanical properties than composites obtained from nanopowders.