Investigating the Effect of Cohesive FSS of the Base Textile and Multilayer Absorbant on Microwave Absorption Properties of Electromagnetic Absorption Coating

In this work, the fabrication of a broadband MAC with a multilayer structure, prepared by carbon nanotube (CNT), silicon carbide (SiC) and carbonyl iron (CI) particles as fillers, was carried out, in which a hexagonal mesh sized knitted polyester fabric was sandwiched between two layers functioning as the frequency selective surface (FSS). The gradient and alternating multilayer structures were simultaneously employed so that a number of optimum main properties, e.g. cost-efficiency, low density along with high and broad band microwave absorbing properties, could be attained. The impact of a single layer sample possessing one type of filler, a single layer sample possessing various types of fillers and a multilayer sample on the above-mentioned main parameters was also studied. Network analyzer was utilized in 4-18 GHz in order to analyze not only the electromagnetic parameters but also the reflection loss (RL) versus frequency of samples by using the transmission/reflection approach. In comparison with other samples, a return loss value as high as 50.80 dB, absorption band width (RL-5 dB) as high as 14.23 GHz and density of 1.73 gr/cm3 could be achieved by using the multilayer MACs with three layers containing multi fillers (CNT, CI and SiC), with various concentrations, and two FSS film interlayers, possessing a 2mm total thickness. Furthermore, to verify the effect of FSS to improve mechanical properties of samples along its effect on microwave absorbing properties, the mechanical properties of samples containing FSS and without FSS analyzed by a standard tensile test instrument.