The purpose of this article is to study the dielectric dispersion of two different ternary composites made of epoxy resin (RE), black iron oxide (Fe3O4) with one of the two titanates (calcium titanate (CaTiO3) or strontium (SrTiO3)) on several frequency bands. Additionally, the effect of the two titanates and the (Fe3O4) on the permittivity and conductivity of these ternary composites is investigated. These composite materials were characterized using time domain spectroscopy (TDS). The inclusion of the two titanates increased the real permittivity and conductivity of the two composites, shifting the resonance frequency (ƒR) towards the low frequency range and causing the opposite phenomenon for the static permittivity (ε s). The frequency dispersion behavior model for the complex permittivity has been proposed to improve the effectiveness of the predictive frequency model through a better choice of the damping factor and to bring theoretical and experimental findings closer together. Comparing these data shows that the proposed model is applicable to ternary combinations with high accuracy. The values of the quality factor (Q) obtained are encouraging in microwave applications. These composite materials witch containing CaTiO3 and SrTiO3 inclusions have contributed to the development of dielectric permittivity that suits very well frequency communication systems.

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In the same matrix of epoxy resin, Fe3O4 powder was evenly mixed with one of two titanate powders, CaTiO3 or SrTiO3. The dielectric properties of these blends were evaluated using the measurement technique of time domain spectroscopy. During this work, low-frequency analyses (DC - 300 MHz) were carried out, mainly focusing on the static permittivity and conductivity properties as a function of titanate concentrations. The results allowed us to confirm the validity and effectiveness of the modified Lichtenecker Laws (MLL). Significant agreement can be shown between the MLL-calculated and experimentally determined permittivity values for ternary combinations. The perspective of this research lies in the production of new materials for use in the field of telecommunications and in particular for microelectronic components.

This study aim is to investigate the ternary composites dielectric behavior and experimentally validate the predictive model that simplifies ternary models into binary ones using time domain spectroscopy (TDS). The scattered white silicon dioxide (SiO2) powder was evenly mixed with barium titanate (BaTiO3 or BT) powder in the same epoxy resin (RE) matrix. Over a frequency range from DC to 30 GHz, the dielectric behavior of these composite samples is examined, adding in particular a low frequency study at 500 MHz. The BT addition grew the mixture dielectric permittivity from 3.6063 to 8.2313 and moving the resonance frequency (ƒr) in the direction of the low frequency from 26.245 GHz until 17.09 GHz. By improving the shape factor smoothing and bringing theoretical and experimental results closer together, this seeks to optimize the modified Lichtenecker's law (MLL). These findings comparison demonstrates that the MLL model applies to ternary composites (RE-BT-SiO2) with an acceptable accuracy level. Another numerical method was used to evaluate the RE-[RE-BT-SiO2] composites employing a binary mixing model based on an MLL equation that is identical to the former ternary. This model results correlate well with binary composites experimental values as well as ternaries that are modeled using this law. This research perspective lies on the production of new materials for use in microelectronics and particularly on the MOS structure oxides improvement.

The RE-ST-FE and RE-BT-FE/FR composites have been prepared and characterized using time domain spectroscopy method in the [DC-12.5] GHz range. The dielectric, magnetic, and electrical properties of the ternary composites have been investigated. In the RE-ST-FE composite, the dielectric permittivity (ε’) has been found to decrease from 9.25 to 3.70 with increase in FE concentration. While it has been observed that the electrical conductivity increases as the ST concentration increases reaching a value of 11.6 (mS / m) and shows a percolation behavior with (Vth = 26,9% ST). In the RE-BT-FE/FR composites, the magnetization hysteresis loops have been measured by vibrating sample magnetometer from -3 to +3 kOe. This has made it possible to have a maximum of saturation magnetization equal 29.3 emu/g and the permeability value close to 1.9 with the RE-BT-FR composite which is considered higher than that of the other one. It was found that an increase in the (FE/FR) concentration increases the magnetic permeability, which is confirmed by the modified Lichtenecker law with error ratio less than 0.5%. The results of this study will undoubtedly yield new materials that can be used to miniaturize electronic components used in telecommunications systems, resonators, antennas and wave absorbers.