Plasma synthesized SiC powder obtained from quartz and carbonaceous residue of waste
tires was successfully sintered at 1925 ℃ by pressureless liquid-phase method using yttria and
alumina as sintering aids (T-SiC). Comparison with sintered SiC obtained from commercial powder
(C-SiC) put in evidence of similar sintered density (98%T.D.), but much finer microstructure of T-SiC
than that of C-SiC. T-SiC also showed higher flexural strength than C-SiC both at room temperature
(508 vs. 458 MPa) and at 1500 ℃ (280 vs. 171 MPa). Difference in liquid phase was responsible for
the differences in hardness and fracture toughness. The high value of the Young’s modulus of T-SiC
(427 MPa) confirmed the high degree of sinterability of this powder and that it can be a promising
candidate for structural applications with high added value.