In this paper, the variation of the resistivity of SiC powder at low and high voltage as a function of milling time was investigated by controlling the particle size, morphology and compactness (applied pressure). The particle shape and size of commercially available SiC powders were altered by ball milling. The electrical properties of the various SiC powders were characterized at low voltage by using a pressure controlled ohmmeter and frequency-domain spectroscopy. A resistivity increase from 7 to 54 MΩ.cm was observed when the grinding time increased from 5 to 30 minutes, which corresponded to a decrease of the particle size from 54 µm to ∼4.5 µm. The nonlinear characterization I–V for high electrical field was investigated. X-ray diffraction and scanning electron microscopy have been carried out to highlight the size decreasing and crystalline structure of the milled powder.
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