W.-Y. Choi, J.-W. Lee, S.-H. Ahn, J.-H. Park, and Y.-S. Choi (Korea)
Electromagnetic wave absorber, Ni-Zn-ferrite, composites, Glass fabric
An electromagnetic wave (EM wave) absorber exhibiting over 10dB attenuation at 1.8GHz was fabricated. In this research, glass-fabric/epoxy composites with various par ticle additives were used in fabricating the absorber, and their abilities in EM wave absorption were compared. The absorber was made in square plate of many layers by stacking glass fabrics impregnated with epoxy and parti cles. For a comparative study, conductive particles such as CNT (Carbon Nano-tube), CNF (Carbon Nano-fiber) and CB (Carbon Black), and magnetic particles such as Ni-Zn-ferrite were used. Each powder showed different characteristics in EM wave absorption. For measuring absorption ability, a system of repeater antenna and spec trum analyzer was used in radiating and detecting the EM wave. Among various absorbers, the absorber using Ni Zn-ferrite showed over 11dB attenuation and exhibited outstanding results. Although CNT or other particles were highly conductive materials, the result showed lower at tenuation than Ni-Zn-ferrite at 1.8GHz. For a microscopic observation of Ni-Zn-ferrite, the SEM (Scanning Electron Microscope) was used which showed the structure of glass fiber, epoxy and Ni-Zn-ferrite particles.
Important Links:
Go Back
