| Title |
The Properties of β-SiC-TiB_2 Electroconductive Ceramic Composites Densified by Liquid-Phase Sintering |
| Authors |
임승혁(Yim, Seung-Hyuk) ; 신용덕(Shin, Yong-Deok) ; 송준태(Song, Joon-Tae) |
| Keywords |
Electroconductive ceramic composite ; YAG(Al_5Y_3O_{12}) ; Eletrcial Resistivity ; Fracture Toughness ; Resistance Temperature Coefficient |
| Abstract |
The mechanical and electrical properties of the hot-pressed and annealed β-SiC-TiB_2 electroconductive ceramic composites were investigated as a function of the liquid forming additives of Al_2O_3+Y_2O_34. The result of phase analysis of composites by XRD revealed α-SIC(6H) TiB_2, and YAG(Al5Y3O12) crystal phase. The relative density and the mechanical properties of composites were increased with increasing Al_2O_3+Y_2O_34 contents because YAG of reaction between Al_2O_3 and Y_2O_3 was increased. The Flexural strength showed the highest value of 432.5MPa for composites added with 12wt% Al_2O_3+Y_2O_34 additives at room temperature. Owing to crack deflection crack bridging phase transition and TAG of fracture toughness mechanism the fracture toughness showed 7.1MPa.m1/2 for composites added with 12wt% Al_2O_3+Y_2O_34 additives at room temperature. The electrical resistivity and the resistance temperature coefficient showed the lowest of 6.0×10-4Ω.cm and 3.1×10-3/°C4 respectively for composite added with 12wt% Ω additives at room temperature. The electrical resistivity of the composites was all positive temperature coefficient resistance (PTCR) in the temperature range of 25°C to 700°C |