Dielectric characterization of heterogeneous materials using two hyper-frequency measurement techniques

Abstract

This thesis focuses on characterizing and studying dielectric composite materials, comprising polymers and ferroelectric ceramics, which have recently emerged as vital components for sustainable energy generation, transformation, and storage applications. Balancing dielectric permittivity, dielectric loss, and dissipation factor is crucial, with the ultimate goal being energy storage capacity. Epoxy resin (RE)/barium titanate (BaTiO3) composite samples are prepared using a mixture cast method with new molds. Dielectric properties, including permittivity, loss, electrical modulus, static conductivity, and dissipation factors influenced by barium titanate concentration and frequency effects, are analyzed via two characterization methods. The study aims to determine material dielectric permittivity using two microwave methods: time-domain spectroscopy (TDS) and X-band microwave test bench (MTB). Various empirical mixture laws are employed to estimate dielectric permittivity. Increasing filler concentration (BaTiO3) correlates with heightened effective dielectric permittivity, confirmed through diverse empirical mixture models. The research findings hold promise for diverse electrical applications, encompassing sensors, wave absorbers, resonators, and antennas.