| Title |
Effect of Annealing Temperature on the Properties of β -SiC-Ti B_2 Electrocondutive Ceramic Composites by Spray Dry |
| Authors |
신용덕 ; 주진영 ; 최광수 ; 오상수 ; 서재호 |
| Keywords |
Spray-dried powders ; Liquid forming additives ; YAG ; Annealing temperature |
| Abstract |
The composites were fabricated respectively 61vo1.% β -SiC and 39vo1.% Ti B_2 spray-dried powders with the liquid forming additives of l2wt% Al_2 O_3＋ Y_2 O_3 by pressureless annealing at 1700°C, 1750°C, 1800°C for 4 hours. The result of phase analysis of composites by XRD revealed α -SiC(6H), Ti B_2, and YAG(A l_{5} Y_3 O_{12} ) crystal phase. The relative density, the Young's modulus and fracture toughness showed respectively the highest value of 92.97%, 92.88Gpa and 4.4Mpa· m^{ frac{1}{2}} for composites by pressureless annealing temperature 1700°C at room temperature. The electrical resistivity showed the lowest value of 8.09×10^{-3} ·cm for composite by pressureless annealing temperature 1700°C at 25°C. The electrical resistivity of the SiC-Ti B_2 composites was all positive temperature cofficient resistance(PTCR) in the temperature ranges from 25°C to 700°C. |