ABSTRACT
During past three decades, extensive and worldwide study has resulted in progress with respect to many aspects of percolation behavior of composites with a single kind of filler. However, composites made with two kinds of filler have not yet been investigated in depth. The percolation behavior of potential grading materials composed of Fe3O4, SiC, and high density polyethylene has been discussed in this study. The electric field dependence of electrical resistivity in the composites above the percolation threshold has been explained without violating the universal law of conductivity. The electrical resistivity of Fe3O4 or SiC filled polymer matrix composites (PMCs) decreased with increasing volume fraction of fillers. The percolation threshold of PMCs is estimated to be 0.25, 0.3, and 0.32 with Fe3O4, SiC, and Fe3O4+SiC filler, respectively. A potential grading layer that has stable and excellent partial discharge suppression capability has been developed.
keyword : composites, extrusion, electrical properties, resistivity, percolation threshold
