基于理论计算指导的FeCo合金泡沫设计合成及其在2.0-8.0 GHz范围内的吸波性能研究OA

Effective electromagnetic(EM)wave absorption with minimal coating thickness in the low-to mid-frequency range(2.0-8.0 GHz)remains a significant challenge.Herein,the EM parameters required for low-to mid-frequency EM wave absorption are systematically investigated,and CST Microwave Studio is employed to model and simulate how these target parameters can be realized through microstructural design.The results demonstrate that increasing the real parts of the relative permittivity(εr')and permeability(μr')is beneficial for achieving low-to mid-frequency EM wave absorption with reduced coating thickness.Moreover,CST simulations reveal that,for the same material system and identical volume filling fraction,increasing the specific surface area of the absorber contributes to an enhancement of εr'.Guided by these principles,FeCo cubes,FeCo particles,and FeCo foams with controlled specific surface areas and high permeability were synthesized.Experimental results confirm that an increased specific surface area effectively enhances εr',thereby promoting low-to mid-frequency absorption.As a result,the FeCo foam achieves an effective absorption bandwidth(EAB)of 3.2 GHz(4.8-8.0 GHz)in the C-band with a coating thickness of 2.0 mm,and 1.5 GHz(2.1-3.6 GHz)in the S-band with a coating thickness of 4.0 mm.This work provides valuable insights into the rational design of advanced low-to mid-frequency EM absorbing materials.