Dielectric behaviour of porcelain in relation to constitution

The dielectric properties of porcelain bodies prepared with and without the incorporation of mineralisers were investigated at different frequencies ( 1-10 MHz) and room temperature (25 degreesC). The phase compositions and mi crostructures of the porcelain bodies were also determined. The influence o f concentrations of mullite, quartz, cristobalite and glass as well as size of mullite crystals and the asymmetry of mullite crystal size distribution on dielectric constant, tan delta and loss factor were examined. The resul ts suggested that frequency of the order of 10(6) Hz had almost no effect o n the dielectric constant but influenced the loss factor substantially. Mul tiple regression equations connecting loss factor with the constitutional p arameters of porcelain bodies were developed to calculate loss factor and t he calculated and experimental values were compared. (C) 2000 Elsevier Scie nce Ltd and Techna S.r.l. All rights reserved.