Microwave-absorbing and mechanical properties of carbonyl-iron/epoxy-silicone resin coatings

Graphene nanosheet- and flake carbonyl iron particle-filled epoxy–silicone composites as thin–thickness and wide-bandwidth microwave absorber

“…The values of the complex permittivity of the absorbers decreased with increasing frequency, which exhibited visible frequency-dependent dielectric response when the absorber was filled with high content of GNs and FCI particles. The dielectric properties of conductive particle-filled insulation resin composites depend on the characteristics of the matrix, the property and volume fraction of the filler, the configuration and internal structure of the composites, and the frequency of the EM wave [6][7][8][9][10][11][12][13][14][15][16]. Both the GNs and FCI particles were included in an insulating resin matrix to constitute heterogeneous composites.…”

“…Various absorbers with matching complex permittivity and permeability, including ferrites, magnetic metallic fillers, nanosized particles, carbon nanomaterials, conductive fibers, frequency selective surface, and even meta-materials, have been developed to design MAMs during the past decades [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Among these absorbers, carbon nanomaterials, such as carbon black, carbon nanotubes (CNTs), carbon nanofiber, graphite platelets, graphene nanosheets (GNs), and graphene (GP), were used as dielectric absorbers owing to their strong microwave absorption [17][18][19][20][21][22][23].…”

“…The RGO-SCI composites exhibited efficient EM wave absorption characteristics (RL < À10 dB) in the range of 7.79-11.98 GHz and a minimum RL of À52.46 dB with a thickness of 3.0 mm. Compared with the SCI particles, flake carbonyl iron (FCI) particles have attracted more interest in MAM application due to their high permeability and matched permittivity, which are mainly attributed to low eddy current loss arising the effects of particle shape and size [8]. In our previous reports, absorbers with simple fabrication techniques and uniform dispersion of multiwalled carbon nanotubes (MWCNTs) and FCI particles have been exploited as efficient EM absorbers [41,42].…”

Microwave complex permeability of planar anisotropy carbonyl-iron particles

“…However, the increasing usage of EM-wave devices results in serious electromagnetic interference (EMI) and electromagnetic compatibility (EMC) problems. A good way to overcome these problems is exploiting a type of microwave-absorbing materials with strong absorption [1][2][3][4][5].…”

Microwave absorbing properties of Ag-coated Ni–Zn ferrite microspheres prepared by electroless plating

“…Offering chemical stability, corrosion resistance and high magnetic loss, ferrites are widely used in either tile or composites form for various EMC engineering practices, depending on the frequency of operation. Iron particles and other magnetic alloy particles are also used in many electronic devices, since they have the advantage of a high magnetic permeability (above Snoek's limit) resulting from high saturation magnetization [6][7][8][9].…”