Integrated Foam‐Type Electromagnetic Wave Absorption Materials

The rapid advancement of information technology in electronic equipment in military and civil fields stimulates the demand for portable and wearable electronic devices. Therefore, lightweight and high-efficiency electromagnetic wave (EMW) absorption materials are intensely demanded. This chapter briefly introduces the advances in integrated foam-type EMW-absorbing materials, including carbon-based foam, ferrite-based foam, silicon carbide (SiC)-based foam, and conductive polymer composite foam. The three-dimensional porous structure of carbon materials has a variety of internal reflections and scattering, further trapping and attenuating EMW. Compared with carbon-based materials and ferrites, SiC-based materials, as dielectric absorbents with tunable dielectric properties and the advantages of chemical and high-temperature stabilities, can meet the application requirements of high-temperature stealth. For polymer-based composite foams, improving the surface impedance matching can effectively promote the incident EMW entering the materials to the maximum extent. High-performance electromagnetic wave-absorbing materials used in high-temperature environments are of great importance in both civil and military fields.