【摘 要】
：
Flexible,lightweight,conductive materials,having both high rf losses and high permeability,are extremely desirable for applications as electromagnetic(EM)shielding.Gas atomized spherical FeSi-based ferromagnetic metallic particles,having a mean diameter o
【机 构】
：
Center for Microwave Magnetic Materials and Integrated Circuits,Department of Electrical and Compute
论文部分内容阅读
Flexible,lightweight,conductive materials,having both high rf losses and high permeability,are extremely desirable for applications as electromagnetic(EM)shielding.Gas atomized spherical FeSi-based ferromagnetic metallic particles,having a mean diameter of 14.6 μm with a standard deviation of 7.3 μm,were measured to have a room temperature saturation magnetic flux density of 1.49 T with a coercivity of 160 A/m.Ball milling of the amorphous particles led to aspect ratios from 1:1(spherical)to＞100:1(flake-like).Flake-like particles,suspended in paraffin,were found to not only increase the surface area of fillers enhancing the polarization mechanism but also increase the complex permeability and complex permittivity,and thus provide broadband shielding effectiveness.A loading factor of 40 vol.％of the～15 μm diameter powders provided the largest △WRL=-20dB of 9.49 GHz(i.e.,6.55＜f＜16.04 GHz)at a coating thickness of 2 mm.Overall,powder composites show a wide absorption potential above 18 GHz for＜1.5 mm thicknesses.The optimized flake-based composites exhibit strong EM wave absorption with an SE of-40 dB and SE＜-10 dB of 17.57 GHz at 40 vol.％filler at a thickness of 1.6 mm.
其他文献
Aging treatment of Cu-based alloys is essential to enhance their strength that is desirable for their exten-sive engineering applications in electrical industry,whereas the underlying mechanism of strengthening is essential for massive manufacturing of th
A valid strategy to tailor the properties of polylactic acid for more extensive applications was introducing filler.In this work,basalt fiber assembled with in-situ SiO2 nanoparticles on the surface was successfully prepared via hydrothermal method and it
Laser 3D printing based on melt growth has great potential in rapid preparation of Al2O3-based eutectic ceramics.In this work,large-scale Al2O3/GdAlO3/ZrO2 ternary eutectic ceramic rod with diameter of 4-5 mm and height higher than 250 mm was additively m
Many metal matrix self-lubricating composites possess excellent comprehensive properties of high strength and wear resistance after incorporating various lubricants that usually belong to ceramic phase.However,this improvement is always obtained at the co
Radial forging(RF)is an economical manufacturing forging process,in which four dies arranged radially around the workpiece simultaneously act on the workpiece with high-frequency radial movement.In this study,a ZK60 magnesium alloy step-shaft bar was proc
Grain-boundary(GB)precipitation has a significant adverse effect on plasticity of alloys,which easily leads to catastrophic intergranular failure in safety-critical applications under high external loading.Herein,we report a novel strategy that uses the l
The effect of reactive element yttrium on purification and carbide precipitation of superalloy K4169 has been studied through vacuum induction melting.The results show that yttrium has a strong deoxidizing and desulfurizing ability,and the impurity elemen
Non-equiatomic high entropy bulk metallic glasses were reported recently and show unique mechanical and physical properties.Dynamic mechanical relaxation behavior of Zr35Hf17.5Ti5.5Al12.5C07.5Ni12Cu10 high entropy bulk metallic glass was investigated by d
It is well documented that the strain rate sensitivity(m)increases at refined grain size for face-centered cubic(FCC)metals and alloys.Through a series of nanoindentation testing,however,we experimentally demonstrated a striking departure from conventiona
Core-shell materials are promising broadband electromagnetic(EM)absorption materials since the highly component manipulation performance,interfacial effect etc.Herein,a well-defined core-shell shaped structure constructed by 2-dimensional MOS2 nanosheets-