Thermophysical properties of porous SiC ceramics fabricated by pressureless sintering

Highly porous SiC with approximately 30–41% porosity was fabricated by pressureless sintering without sintering additives at temperatures in the range 1700–2000 °C. Thermal diffusivities, specific heats, thermal conductivities and thermal resistivities of sintered samples are reported for temperatures from room temperature to 1000 °C. The thermal diffusivities and thermal conductivities of all samples decreased significantly with increasing temperature over this range, whereas specific heats and thermal resistivities increased. At any given temperature, the greater the porosity of the SiC, the lower the thermal conductivity.