Fabrication of short-C_f/SiC functionally graded materials

By using Spark Plasma Sintering (SPS), homogeneous SiC composites reinforced with unidirectional short carbon fibers were sintered. And (Al₂O₃+graphite), (AlN+graphite) and (B₄C+graphite) are added respectively as additives in order to achieving high densification. The effects of these additives on the densification of short-C_f/SiC composites are investigated, and their influences on carbon fibers are also analyzed. Then by adjusting the additive amount of suitable additives, homogeneous short-C_f/SiC composites with different bulk ratio are densified at the same sintering conditions. Finally, these homogeneous composites are stacked layer by layer and formed FGM. And as a result, short-C_f/SiC functionally graded materials, in which the volume distribution of short C_f changes gradually along the thickness orientation, were successfully fabricated.