Design and study of a hybrid composite structure that improves electromagnetic shielding and sound absorption simultaneously

A novel hybrid composite structure is proposed, which can shield electromagnetic pollution and substantially increase sound absorption at the same time. The structure can be prepared using a facile manufacturing method. The theoretical model, FEM simulation, and experimental results indicate that the hybrid composite structure has an electromagnetic shielding efficiency of more than 90 dB in the X band. In addition, the sound absorption coefficient was greatly improved compared to the pure porous material (conductive sponge). This confirms that two different propagation modes (electromagnetic waves and sound waves) can be manipulated with a single structure. The dual-function design also opens new possibilities to create metamaterials, and it can be used to reduce electromagnetic and noise pollution.