The Design and Electromagnetic‐Wave‐Absorbing Performance of a Broadband Four‐Layer Absorbing Composite

A four‐layer absorbing composite on millimeter scale is designed containing an absorbent with multilayer‐like structure on the microscale. In this four‐layer absorbing composite, epoxy resin acts as transparent layer, the multilayer‐like structure absorbent serves as the main absorbing layer; graphene/Ni composite acts as an impedance matching layer; and Fe₃O₄ nanoparticles serve as a magnetic‐loss absorbing layer. The reflection loss of the composites is simulated with CST Microwave Studio, and the absorbency of the composites is discussed in detail when the thickness of each layer is changed. The results show that when the thicknesses of the transparent layer, main absorbing layer, impedance matching layer, and magnetic‐loss absorbing layer are 2.5, 2, 1.5, and 2 mm, respectively, the minimum reflection loss of the composite is ?51.7 dB, the bandwidth below ?10 dB reaches 11.82 GHz, and the density of the composite is nearly 1.9 g cm^?3. Therefore, this new four‐layer absorbing composite possesses strong absorbency, broad absorbing bandwidth, thin thickness, and light weight. Thus, a new way to the development of multilayer absorbing composites is presented.