A carbon/silica composite designed for use under compressive loads was fabricated from rice husk (RH),
an agricultural waste material. RH was pulverized by using a planetary ball mill, then carbonized and
molded into the precursor by means of hot-pressing without using any binders. A compression of
100 MPa was intermittently applied to the RH powder heated from room temperature to 150 C, and then
to 280 C. The precursor, the bulk density of which was 1.37 g/cm3, was sintered for further densification
at up to 1400 C without compression, in nitrogen gas. The smaller particle size of the pulverized RH was
beneficial for densifying the carbon/silica composite and increasing its compressive strength. Sintering at
800 C for 1 h in nitrogen gas provided the maximum bulk density of 1.52 g/cm3 and the maximum Vickers
hardness at the surface of 343 HV. The maximum compressive strength was measured to be 55.7 MPa
using a sintering temperature of 1200 C.