Conventional powder processing is commonly used to fabricate Al2O3/SiC nanocomposites, in which SiC is added in a powder form with sizes of tens to hundreds nanometres. Recently a new processing route using a SiC polymeric precursor such as polysilazane, polysilastyrene, or polycarbosilane has been also attempted, where a polymeric precursor solution is mixed with alumina powder. The resulting powder is dried and heal-treated or sintered to form nano-sized SiC particles in situ by the pyrolysis of the polymeric precursor. In this study, porous alumina bodies were infiltrated with the hexane solution of polycarbosilane and sintered at 1600degreesC for 2 h in Ar or N-2. The densification and phase formation behavior was studied as was the effect of SiO2 addition.
Keywords: Al2O3/SiC nanocomposites, Plycarbosilane, Infiltration, Sintering.