Dielectric Loss and Insulation Resistance of Bodies Made from Chlorite, Pyrophyllite, and Sericite

Abstract

The single component bodies of chlorite, pyrophyllite, and sericite, as well as those made from the mixture of chlorite-quartz, pyrophyllite-quartz, and pyrophyllite-sericite were fired to measure shrinkage and absorption. The addition of a small amount of alkaline earth oxides on their physical properties, colour and the degree of vitrification were also noted. The measurements of dielectric loss and insulation resistance were also made using the specimens having smaller porosity values.In general, the chlorite and chlorite-quartz bodies showed high insulation resistance and low dielectric loss, but they had high shrinkage. Chlorite body, and some bodies in the series of pyrophyllite-chlorite had also low dielectric loss, but they were of low insulation resistance. The bodies in the series of pyrophyllite-sericite had high loss factors and low, although some of them had low dielectric loss.Large variatin in the properties such as the range of vitrification, dielectric loss, and insulation resistance etc. followed from the variation in the amount, and the property of the alkali earth oxides added to the body. Bodies having high insulation resistance were not necessarily those having a low dielectric loss.