Dielectric properties of ceramic composite materials based on alumina reinforced by titanium carbide

Abstract

The aim of this research work is to study the dielectric and microwave properties of the three ceramic composites Al2O3-TiC, Al2O3-0.3TiC and Al2O3-0.7TiC. The results obtained show that the effective permittivity increases with the increase in the filling rate of titanium carbide TiC inclusions and their contrasts. As for the classical mixing laws, they make it possible to estimate permittivity for low volume fractions and low contrasts. The values of the real part of the complex permittivity decrease with frequency increase in the two bands X and Ku, while the imaginary part is approximately constant in the X band and takes negative values in the Ku band.

Permittivity of SiC ceramic matrix compositesin Ku band

“…This indicates that the filling rate effectively improves the complex permittivity parameters of the composite material. As the volume fraction increases, more mobile charges are produced at the interfaces, leading to an improvement of the electronic polarization and relaxation polarization [4]. Therefore, the real part of the permittivity increases with the increase of the volume fraction.…”

“…The latter takes negative values when the frequency increases from 12 GHz to 18 GHz.The results obtained in this work indicate the existence of dielectric losses in the composites studied for the high frequencies. This behavior is due to the relaxation losses of the polarization by the hysteresis between the displacement current and the accumulation potential when the frequency increases [1,16].…”

“…The knowledge of the dielectric permittivity of composite materials is important for several applications [1,2,3], particularly in telecommunications, industry and the design of radarabsorbing materials (RAM) [4]. SiC Ceramic matrix composites reinforced by silicon carbide SiCfibers, such as Nicalonfibers, have become important in various applications [5].…”

“…In the literature, several methods have been used to determine the complex permittivity of materials [1]. The Transmission/Reflection (T/R) technique is one of the most adopted methods to characterize materials in the wide frequency range [8].…”

Complex permittivity of FeSiAl/Al2O3 ceramic composite at X-band frequencies

“…The use of materials in applications requires accurate knowledge of the complex permittivity [9]. In the literature, several methods have been used for the extraction of the complex permittivity of materials [9].…”