SiC structural materials present good properties such as high resistance to wear and to oxidation and high thermal shock resistance. Al2O3 (4wt.%), Y2O3 (4wt.%), polymetylhydrogensiloxane and polymetylhydrogensiloxane with D4Vi were the sintering aids for SiC. The processing procedures were material cure, pyrolysis (500 ºC and 900 ºC/1 h) and sintering (1850 ºC and 1950 ºC/1 h, Ar). Silicon carbide based ceramics with polymer sintering aids achieved 3.0 g/cm³ density after pyrolysis at 900 ºC/1 h and sintering at 1950 ºC/1 h. The effects of the addition of precursor polymers on microstructure and hardness of silicon carbide ceramics were studied. The preparation of ceramic composites using small amounts of precursor polymers shows a suitable process for SiC-based ceramics, even with high mass loss. It is a simple forming route, with high potential for the fabrication of complex shape pieces.
SiC; polysiloxane; microstructure; hardness