Title |
Properties of SiC-ZrB_2 Electroconductive Ceramic Composites by Spark Plasma Sintering |
Authors |
주진영(Ju, Jin-Young) ; 이희승(Lee, Hui-Seung) ; 조성만(Jo, Sung-Man) ; 이정훈(Lee, Jung-Hoon) ; 김철호(Kim, Cheol-Ho) ; 박진형(Park, Jin-Hyoung) ; 신용덕(Shin, Yong-Deok) |
Keywords |
Spark Plasma Sintering(SPS) ; Negative Temperature Coefficient(NTCR) ; Heater ; Electrode ; V-I characteristic |
Abstract |
The composites were fabricated by adding 0, 15, 20, 25[vol.%] Zirconium Diboride(hereafter, ZrB_2) powders as a second phase to Silicon Carbide(hereafter, SiC) matrix. The physical, mechanical and electrical properties of electroconductive SiC ceramic composites by Spark Plasma Sintering(hereafter, SPS) were examined. Reactions between {β}-SiC and ZrB_2 were not observed in the XRD analysis. The relative density of mono SiC, SiC+15[vol.%]ZrB_2, SiC+20[vol.%]ZrB_2 and SiC+25[vol.%]ZrB_2 composites are 90.93[%], 74.62[%], 74.99[%] and 72.61[%], respectively. The XRD phase analysis of the electroconductive SiC ceramic composites reveals high of SiC and ZrB_2 and low of ZrO_2 phase. The lowest flexural strength, 108.79[MPa], shown in SiC+15[vol.%] ZrB_2 composite and the highest - 220.15[MPa] - in SiC+20[vol.%] ZrB_2composite at room temperature. The trend of the mechanical properties of the electroconductive SiC ceramic composites moves in accord with that of the relative density. The electrical resistivities of mono SiC, SiC+15[vol.%]ZrB_2, SiC+20[vol.%]ZrB_2 and SiC+25[vol.%]ZrB_2 composites are 4.57×10^{-1}, 2.13×10^{-1}, 1.53×10^{-1} and 6.37×10^{-2}[{Ω} cm] at room temperature, respectively. The electrical resistivity of mono SiC, SiC+15[vol.%]ZrB_2. SiC+20[vol.%]ZrB_2 and SiC+25[vol.%]ZrB_2 are Negative Temperature Coefficient Resistance(hereafter, NTCR) in temperature ranges from 25[°C] to 100[°C]. The declination of V-I characteristics of SiC+20[vol.%]ZrB_2 composite is 3.72×10^{-1}. It is convinced that SiC+20[vol.%]ZrB_2 composite by SPS can be applied for heater or electrode above 1000[°C] |