Conductive grid effects in magnetic composites on power absorption

To evaluate the electromagnetic power absorption in near field, the magnetic composites with the conductive grids were fabricated. The magnetic composites were composed of the 50 wt.% NiFe nanoparticles and silicon rubber. The transmission power absorptions of the magnetic composites on a microstrip line were measured by vector network analyzer up to 6 GHz. The measuring results were compared with those of the 3D FEM simulation results. By the insertion of the conductive grid in magnetic composite, the power absorption ratio was greatly increased from about 20% to 80% and the bandwidth of the absorption frequency broadened from about 2 GHz to 5 GHz, respectively, in comparison with those of the magnetic composite without conductive grid.