The Development of an Electroconductive SiC-ZrB₂Composite through Spark Plasma Sintering under Argon Atmosphere

Abstract

-The SiC-ZrB 2 composites were fabricated by combining 30, 35, 40, 45 and 50 vol. % of zirconium diboride (ZrB 2 ) powders with silicon carbide (SiC) matrix. The SiC-ZrB 2 composites and the sintered compacts were produced through spark plasma sintering (SPS) under argon atmosphere, and its physical, electrical, and mechanical properties were examined. Also, the thermal image analysis of the SiC-ZrB 2 composites was examined. Reactions between β-SiC and ZrB 2 were not observed via x-ray diffraction (XRD) analysis. The apparent porosity of the SiC+30vol.%ZrB 2 , SiC+35vol.%ZrB 2 , SiC+40vol.%ZrB 2, SiC+45vol.%ZrB 2 and SiC+50vol.%ZrB 2 composites were 7.2546, 0.8920, 0.6038, 1.0981, and 10.0108%, respectively. The XRD phase analysis of the sintered compacts demonstrated a high phase of SiC and ZrB 2 . Among the SiC+ZrB 2 composites, the SiC+50vol. %ZrB 2 composite had the lowest flexural strength, 290.54MPa, the other composites had more than 980MPa flexural strength except the SiC+30vol.%ZrB 2 composite; the SiC+40vol.%ZrB 2 composite had the highest flexural strength, 1011.34MPa, at room temperature. The electrical properties of the SiC-ZrB 2 composites had positive temperature coefficient resistance (PTCR). The V-I characteristics of the SiC-ZrB 2 composites had a linear shape in the temperature range from room to 500℃. The electrical resistivities of the SiC+30vol.%ZrB 2 , SiC+35vol.%ZrB 2 , SiC+40vol.%ZrB 2 SiC+45vol.%ZrB 2 and SiC+50vol.%ZrB 2 composites were 4.573×10 -3 , 1.554×10 -3 , 9.365×10 -4 , 6.999×10 -4 , and 6.069×10 -4 Ω·cm, respectively, at room temperature, and their resistance temperature coefficients were 1.896×10 -3 , 3.064×10 -3 , 3.169×10 -3 , 3.097×10 -3 , and 3.418×10 -3 /℃ in the temperature range from room to 500℃, respectively. Therefore, it is considered that among the sintered compacts the SiC+35vol.%ZrB 2 , SiC+40vol.%ZrB 2 and SiC+45vol.%ZrB 2 composites containing the most outstanding mechanical properties as well as PTCR and V-I characteristics can be used as an energy friendly ceramic heater or ohmic-contact electrode material through SPS.

Spark plasma sintering of structure‐tailored ultrahigh‐temperature components: First step to complex net shaping

“…The material considered in this study is a ceramic composite consisting of SiC and ZrB 2 . Previous studies have reported that the SPS‐processed SiC–ZrB 2 ceramic composites possess high flexural strength (~1 GPa) and good electrical resistivity (~10 −3 Ω·cm) at room temperature . At elevated temperatures, this kind of composite also exhibits an excellent flexural strength .…”

“…SiC powder (99.9% pure, <1 μm, Materion Advanced Material Group, Milwaukee, WI, USA) and ZrB 2 powder (99.5% pure, −325 mesh; Materion Advanced Material Group, Milwaukee, WI, USA) were utilized as starting materials. The volume percentage of ZrB 2 in the target powder composite was set to 40% as it has been reported by Lee et al, to be the optimal ratio. The mixed SiC and ZrB 2 powders were ball‐milled for 8 hours at 60 RPM to homogenize the particle distribution.…”

Optimization of Spark Plasma Sintering Technology by Taguchi Method in the Production of a Wide Range of Materials: Review

“…He stated that the overriding capability of a process should include not only the production of efficiency but should also comply with the target value. Any deviation from the target results in a loss of quality and a decrease in customer satisfaction [ 47 ].…”

Effects of SPS Mold on the Properties of Sintered and Simulated SiC-ZrB2Composites

“…However, the addition of SiC to ZrB 2 results in the formation of a SiC-ZrB 2 composite with high electrical conductivity, superior oxidation resistance, and high mechanical strength. These properties make SiC-ZrB 2 composites suitable conductive materials and Ohmic-contact electrode materials, able to function satisfactorily at both high and low temperatures [5][6][7].…”