Experimental Study on Tunable Electromagnetic Shielding by Microlattice Materials with Organized Microstructures

Porous metal materials are widely used for preventing electromagnetic interference, control of heat conduction and impact absorbing. However, a limitation associated with porous metals is that their irregular and non-uniformal microstructures make their functions non-desirably tunable. In this report, the authors propose a microlattice material with precisely controlled microstructures for electromagnetic (EM) shielding. An effective medium model taking into account of the EM stimulated surface current of the metal wires is developed to characterize the EM shielding effect of the microlattice metal. In addition, a compact and integrated measuring device is constructed by using a 3D printing method for experimental verification. The theoretical predictions agree well with the experimental measurement. The influence of the geometrical parameters of the microlattice metals on EM shielding effect is also studied. The theoretical model and the compact measuring system provide robust and efficient tools for the design of EM shielding materials.