Study of dielectric properties of high-energy radio-absorbing composites

The solution of problems in the field of microwave electrotechnology related to mathematical modelling, development of installations or technology of electromagnetic field influence on the processing object requires knowledge of dielectric properties of high-energy radio-absorbing composites. The paper presents the results of computational and experimental study of dielectric properties of composite materials based on epoxy matrix with different absorbing fillers. Dielectric properties of materials were determined using the waveguide method based on the determination of the complex reflection coefficient and passage of electromagnetic waves through the working chamber with the investigated sample. By means of modelling the electric field strength distribution, the optimum geometry of the electromagnetic wave in the measuring microwave line (frequency — 2450 MHz) was found. It was found that the use of silicon carbide as an absorbing filler in the composite is very promising, providing a high temperature of its heating at dissipation of microwave energy. At the same time, the results of in-situ experiment of measuring dielectric properties of composites with different fillers and numerical results showed convergence with an error of 14%. The obtained results can be used in the creation of new radio-absorbing composites on the polymer basis with a given complex of functional properties.