In order to enhance the shielding performance of material against electromagnetic wave and reduce the harms caused by the secondary electromagnetic wave reflection at the same time,based on the synergistic effect mechanism of electric-magnetic loss,compounding magnetic loss material carbonyl iron powder (CIP),which was modified by mechanical ball milling and coated with silica (SiO2),with silver-plated fabric to prepare composite electromagnetic shielding fabric combining absorbing layer and reflecting layer.The phase characterization of the modified CIP was carried out by microscopic imager,XRD and FT-IR.The electromagnetic parameters and shielding efficiency of the modified CIP and composite fabric were tested and analyzed by coaxial method and waveguides method.The experimental results showed that the band width of electromagnetic wave absorption loss of the doubly modified carbonyl iron powder increased and the optimal reflection loss was -62.7dB.When the overall thickness of the coating and the substrate was 3mm,the reflectance (R) of the composite to electromagnetic wave decreased from 0.96 to 0.2,and the absorption rate (A) increased from 0.03 to 0.82,which realized the shielding effect dominated by absorption.
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基金资助
新疆维吾尔自治区自然科学基金-青年科学基金项目(2021D01C094);天山青年计划项目(2020Q073);天池博士计划项目(TCBS202012)
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