Effect of chemical modification conditions on the sintering behavior of TiC powders

Resumo

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°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°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/cm³, 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.