How Microwave Impact On Porcelain Dielectric Properties

Abstract

This work deals with influence of ceramic processes parameters like moisture, compaction pressure and heating source (electric resistance and hybrid microwave) on dielectric properties of a sintered translucent porcelain. Several porcelain samples were prepared with two levels of moisture (3% and 6%) during the pressing process and two levels of hydraulic pressure (100 and 174 MPa) before drying; porcelain composition was kaolin (43%), potassic feldspar (36%), quartz (17%), bentonite (1%) and wollastonite (3%). Dielectric properties of the green porcelain were measured, and the results induced the use of a hybrid microwave furnace. Dried porcelain samples were sintered at 1200 oC with an electric furnace (7000 W) and with a microwave hybrid furnace (1600 W of microwave with silicon carbide as a susceptor). The dielectric properties of the sintered porcelain were measured. The results were statistically analyzed with Yates' method and variance analysis; it was proved that sintering with microwaves has a significative influence on the dielectric constant and loss tangent with 99.9% of confidence. Compaction pressure level impacted loss tangent value with 99% of confidence and moisture level (at pressing) impacted dielectric constant with 90% of confidence. Multivariate regressions for the green porcelain dielectric constant and loss tangent were determined. © AMPERE 2021. All rights reserved.