Effect of Chemical Modification Conditions on the Sintering Behavior of TiC Powders

摘要

Dense ceramics have been produced from a chemically modified titanium carbide powder. Chemical modification was carried out by siliciding titanium carbide powder in a gaseous SiO atmosphere at 1350 degrees C. This treatment produced a Ti3SiC2 layer (up to 19 wt %) on the surface of the TiC particles. Hot pressing at a temperature of 1600 degrees C and pressures from 10 to 20 MPa ensured effective densification of the modified powders. The density of the resultant material reaches 4.8 g/cm(3), with a residual porosity under 2%. Its bending strength and fracture toughness are 330 +/- 50 MPa and 6.2 +/- 0.6 MPa m(1/2), respectively.