Abstract:SiC coating modified Cf by CVD, then fabricated (SiC)Cf / Si3N4 composite by gelcasting. The effect
of (SiC)Cf content toward the mechanical and absorbing properties of the composite were investigated. The flexure
strength of (SiC)Cf / Si3N4 composites reduced 112 MPa compare with Si3N4 ceramic and the fracture toughness increase
11. 5 MPa·m1/2 when the (SiC)Cf content is 10wt%, meanwhile both the real (ε') and imaginary (ε″) permittivity
of (SiC)Cf / Si3N4 composite ceramics reached maximum, the dielectric constant ε' is about 15 to 18 and ε″
is about 6 to 8; the reflectivity of the composites moved to a lower frequency with the (SiC)Cf content and thickness
increased.