Dielectric Properties of Lithium Silicate Fired by Spark Plasma Sintering

Abstract

This paper aims to study various physical properties of lithium silicate ceramics. The work starts with the synthesis followed by characterization of the compounds. The samples are synthesized by reaction between SiO2 and Li2CO3 powders, compacted by spark plasma sintering (SPS) and then characterized by XRD, SEM and other techniques. The electrical properties are studied by dielectric spectroscopy. Dielectric and conductive properties of lithium silicate depend on the composition and microstructure, which factors are interconnected with the processing parameters. Li2SiO3 and Li2Si2O5 were the major components present in the SPS bulk. The best combination of dielectric parameters is relative permittivity 6.41 and loss tangent 0.001 at frequency 0.9 MHz for the sample sintered at 950 °C for 30 min. Relative permittivity as well as loss tangent was monitored to increase with temperature up to 250 °C.