Enhanced sintering of SiC using infiltration of preceramic polymer

The effects of infiltrated preceramic polymers on the formation and sintering of SiC ceramics were investigated. Polysilazane was chosen as SiC precursors. Partially sintered SiC specimens were infiltrated with preceramic polymer by vacuum infiltration and ultrasonic stirring. The specimens infiltrated with the preceramic polymers were cured at 200-250 degrees C. The specimens were then sintered at 2000-2100 degrees C in flowing Ar atmosphere. The preceramic polymers were converted to SiC during heating. After sintering, the densification behavior and microstructure of the specimens were analyzed. The bending strength and Vickers hardness were measured and discussed. (C) 2011 Elsevier Ltd and Techna Group S.r.l. All rights reserved.