Bulk Resistivity of SiC and Carbon Materials in the Silicon Furnace

The amount of current that will pass through the charge material in the silicon furnace depends on the resistivity of the charge mix because the path will favor least resistance. Thus, this work seeks to examine the conductivity of various materials found in the silicon furnace, namely SiC and various carbon materials and isolate three main factors: carbon source, particle size, and type of SiC material. Charcoal is the least conductive carbon material, followed by char, then coal, and finally coke. The SiC material made from coal and char follows the same trend as the corresponding carbon materials, with the exception of deviations around 1200°C, likely due to volatiles. Compared to the carbon material from which it is made, the SiC material appears to be only slightly more conductive at high temperatures. SiC materials from different carbon sources, in this case from coal and char, appear to have conductive properties of the same magnitude, but the difference in resistivity between the two decreases with increasing temperature and their compositions are similar in range. Particle size does appear to affect the bulk resistivity of the SiC materials, although how it is affected is still disputable, as the results show conflict with previous findings.