Ultra-broadband electromagnetic shielding properties of Cu/Ni coatings on CFRP

Abstract

In view of the increasingly frequent electromagnetic interference(EMI) problem of unmanned aerial vehicles (UAVs) and electronic information equipment, the study of metal coating on carbon fiber reinforced plastic(CFRP) that is resistant to ultra-broadband EMI has become an important research direction in the field of electromagnetic protection. In this paper, an electromagnetic shielding coating system of CFRP substrate with high efficiency and ultra-broadband electromagnetic shielding performance is studied. A Cu/Ni gradient coating system with high efficiency electromagnetic loss is prepared by using an electroless plating Cu-electroplating Ni composite process. The research systematically examines the variation patterns of electromagnetic parameters and elucidates the electromagnetic loss mechanisms of the Cu/Ni coating system on the CFRP. The 8.49 µm Cu-Ni-Cu-Ni ultra-thin coating has a peak shielding performance of 60.3 dB in the X-band and 42.8 dB in the Ku-band. The electromagnetic shielding performance is 10–20 dB higher than millimeter-level materials such as hydrogel. Experimental results show that the Cu-Ni-Cu-Ni gradient coating system constructs a conductive network through interface electromagnetic coupling to regulate impedance matching and spatial polarization mechanisms, thereby improving ultra-broadband electromagnetic shielding performance. This paper provides a theoretical basis and technical approach for the development of a new generation of lightweight broadband electromagnetic shielding materials and has important engineering application value for improving the electromagnetic shielding capability of electronic information equipment.