The liquid phase sintering of silicon carbide (SiC) with additions of Al2O3 , Y2O3 and ZrO2 was studied. The high energy milling process resulted in the secondary additivation of the powder, being ZrO2 the major phase. The final microstructures showed a strong influence of the crystalline phases on the average size of the particles, as well as on the ZrO2 content. The secondary additivation of ZrO2 and the consequent formation of the ZrC phase showed a beneficial effect on densification. The sintering obtained by ultrafine powders with milling times of 4 and 6 h and with ZrO2 contents of 12% and 16%, respectively presented values of apparent densities higher than 95%.
sintering; nanopowders; SiC; secondary additivation; ZrO2
