This review aims to summarise the progress in some materials and structures for electromagnetic applications, such as microwave absorption, electric shielding and antenna designs, which have been developed in recent years. Composites with spherical powders for microwave absorption focus mainly on those based on ferrites (especially hexagonal), carbonyl iron and related alloys and various newly emerged nanosized materials. Composites with long conductive fibres as fillers will be summarised, with speical attentions to prediction, measurment and evaluation of their performances. Metamaterials include structures for microwave absorbing applications, tunable materials or structures with reflection or transmission coefficients that are tunable by external magnetic or electric fields, and specially designed structures for microwave absorbing applications, with thickness much smaller than that of conventional composite materials and performances that can be optimised by the physical properties of substra...

Recent progress in some composite materials and structures for specific electromagnetic applications

Synthesis and microwave absorption properties of FeCo nanoplates

Synthesis and microwave absorbing properties of FeCo alloy particles/graphite nanoflake composites

Flower-like FeNi@C nanocomposites self-assembled by FeNi nanosheets and flocculent carbon were synthesized by the hydrothermal method. The electromagnetic parameters of FeNi@C–paraffin composites were measured at 0.03–18 GHz. Dual dielectric relaxations were observed in the composite system due to the cooperative consequence of the FeNi–C interfaces and dielectric carbon. The strong magnetic loss is from the coexistence of natural resonance and exchange resonance. For the 2.0 mm thickness layer, an optimal reflection loss (RL) of −46.7 dB is observed at 3.17 GHz, whereas the absorbent with a thickness of 1.3 mm has an RL of −32.78 dB at 13.78 GHz. The excellent microwave absorption abilities result from the synergy of dielectric and magnetic losses and quarter-wavelength cancellation.

Enhanced microwave absorption of flower-like FeNi@C nanocomposites by dual dielectric relaxation and multiple magnetic resonance

Constructing 1T/2H MoS2 nanosheets/3D carbon foam for high-performance electromagnetic wave absorption.

FeCo nanocapsules with FeCo alloy as core and amorphous Al(2)O(3) as shell have been synthesized by a modified arc-discharge technique Three-dimensional coral-like aggregates are self-assembled by the nanocapsules in the arc-discharge process The FeCo nanocapsules are ferromagnetic at room temperature The electromagnetic-wave absorption properties of FeCo nanocapsules were investigated in the frequency range from 2 to 18 GHz A reflection loss exceeding -20 dB was obtained in the frequency range of 52-159 GHz for absorber thicknesses of 2-4 mm An optimal reflection loss of -448 dB was reached at 128 GHz for an absorber thickness of 3 mm As a result, these FeCo nanocapsules may be applied in high-frequency electromagnetic-wave absorption (C) 2008 American Institute of Physics [DOI: 101063/12982411]

Electromagnetic-wave absorption properties of FeCo nanocapsules and coral-like aggregates self-assembled by the nanocapsules

Erratum: “Electromagnetic-wave absorption properties of FeCo nanocapsules and coral-like aggregates self-assembled by the nanocapsules” [J. Appl. Phys. 104, 064319 (2008)]

H. Meng

Papers

Electromagnetic-wave absorption properties of FeCo nanocapsules and coral-like aggregates self-assembled by the nanocapsules

Erratum: “Electromagnetic-wave absorption properties of FeCo nanocapsules and coral-like aggregates self-assembled by the nanocapsules” [J. Appl. Phys. 104, 064319 (2008)]