Development of Hybrid Polymer Composites for Electronic Warfare Casings and Investigation of Electromagnetic Interference Shielding Performance

Modern aircraft rely on electronic warfare (EW) systems to ensure dependable and continuous functioning. However, due to their susceptibility to EMI in busy signal environments, they require high-performance shielding solutions. Traditional metallic casings, while effective, significantly increase the overall weight of EW systems, driving the defense industry's demand for lightweight, multifunctional polymer composites. Here we present a new avenue to address this need through the development of high-performance composites using an acrylonitrile butadiene styrene (ABS) matrix with hexagonal boron nitride (h-BN) and carbon nanotube (CNT) fillers. These materials were selected for their exceptional thermal and electrical properties. The composites were meticulously prepared using twin-screw extrusion, and test samples were precisely formed via injection molding. Our results indicate an impressive 100% improvement in EMI shielding effectiveness in the h-BN and CNT-reinforced ABS composites compared to unmodified ABS, as validated by waveguide measurements. Furthermore, a novel design incorporating the composite mixture between two thin aluminium 6061 T6 plates achieved a substantial 50 dB shielding effectiveness, meeting the stringent requirements for military platforms. This research presents a significant advancement in developing lightweight, yet highly effective, EMI shielding solutions for next-generation EW systems.