Microwave Heat-Treated Electronic Waste Constituted X-Band Radar Absorbing Structure Using Electromagnetic Mixing Model Assisted Optimization Strategy

Potential radar absorbing material (RAM) for suppressing electromagnetic (EM) wave over a range of oblique angles of incidence are needed in many applications. In this article, an attempt is being made to build cost-effective and efficient RAM using the EM characterization of microwave heat-treated (MHT) electronic waste followed by an EM mixing model-assisted analytical approach. The robust and facile top-down fabrication technique is employed for the development of heterogeneous composites, which are further subjected to microwave heat treatment at distinct power wattages. The magneto-dielectric spectrographic analysis of samples is carried out in the range of 8.2 to 12.4 GHz. The Debye parameters are optimized and succeeded to obey EM property of the synthesized samples. Jaya's algorithm is adopted for the optimal design of single and dual-layer RAMs at normal and oblique angle incidence based on the constitutive EM parameters under certain restrictive conditions. The embraced MHT method prompts an improvement in microstructure coherency that further increases absorption bandwidth (BW). As a result, a 2.1 mm thick single layer RAM achieves a minimum reflection coefficient (RC) of -17.1 dB at 10.3 GHz with a 100% BW below -10 dB threshold. The groundbreaking findings are obtained by performing a three-fold study of dual-layer RAMs, culminating a minimum RC of -47.8 dB at 11.8 GHz with a layer thickness of 1.8 mm. This article shows that the microwave heat-treated composites have enormous potential in the development of lightweight and broadband RAMs for stealth applications.