FABRICATION AND CHARACTERIZATION OF CONDUCTIVE GLASS COMPOSITES WITH NETWORKS OF SILICON CARBIDE WHISKERS

摘要

In this study, borosilicate glass composites were fabricated using glass microspheres and silicon carbide whiskers (SiCw). These composites have a great deal of potential application in microwave heating and EMI shielding. The microsphere/SiC_w composites were fabricated by hot pressing at relatively low temperatures and pressures in order to control the viscous flow of the glass so that it would segregate the SiCw to specific areas in the composite. This resulted in the formation of percolating SiCw networks at volume fractions around 5-7.5% and a change in about 5-6 orders of magnitude in resistivity, which is typical for these types of composites. Since the SiC_w have a large aspect ratio, the electrical properties were measured in both the parallel and perpendicular direction. Due to the processing method that was intended to form segregated networks, the difference in the resistivity along the two directions was not that large and the small disparities that exist at certain concentrations is likely due to a slight flattening of some of the glass particles due to the hot pressing.