Fast fabrication of SiC particulate-reinforced SiC composites by modified PIP process using spark plasma sintering – effects of green density and heating rate

SiC particulate-reinforced SiC ceramic matrix composites (SiC_p/SiC) were fabricated by a modified polymer infiltration and pyrolysis (PIP) process using spark plasma sintering (SPS). The effects of pyrolysis conditions, green density, and polymer infiltration method on the densification and properties of the SiC_p/SiC were investigated. SiC_p/SiC with high relative density up to 88.06 % was fabricated after 4 PIP cycles by adopting high green density of SiC pellet (76.5 %) provided from drying the high solid loaded (70 vol. %) SiC slurry and fast SPS pyrolysis. The highest hardness of 21.05 ± 2.4 GPa was achieved for the as-fabricated SiC_p/SiC, and the hardness value increased up to 23.99 ± 1.8 GPa after heat treatment at 2000℃. The improvement was attributed to the thermally stable SiC fillers, and partial sintering between the fillers and precursor derived ceramics (PDC) matrix. The excellent mechanical property, thermal stability, and short processing time render the SiC_p/SiC composite a challenging candidate for high-temperature application.