With the help of combustion synthesis under high gravity

TiC-TiB2 fine-grained composite ceramics with different TiB2 contents were prepared by rapid solidification method.Microstructure and mechanical properties of the prepared composite ceramics were investigated by XRD（X-ray diffraction）

FESEM（field emission scanning electron microscope） and EDS（energy dispersive spectrometer） as well as tensile testing.The results reveal that

with increasing in TiB2 content

microstructure of the TiC-TiB2 composite ceramics is composed of those from fine TiC spherical grains to fine TiB2 platelet structure

whereas when TiB2 content reaches 50%（in atom fraction）

ceramics consist of eutectic structure where small-sized TiB2 platelets are embedded in TiC matrix.Relative density and Vickers hardness of TiC-50TiB2 reach up to maximum value（as 98.6% and 18.4GPa

respectively） as a result of eutectic reaction during solidification

meanwhile

TiC-66.7TiB2 ceramics exhibit maximum fracture toughness of 13.4MPa·m1/2 as a result of the cooperative action of crack deflection

crack-bridging and pull-out toughening from fine TiB2 platelets.