We developed composite electromagnetic wave absorbers dispersed aluminum fine particles in polystyrene medium and evalated those properties in order to realize single layer electromagnetic wave absorbers with the good absorption property in the GHz region. Polystyrene particles with two kind of diameters (approximately 200 μm or 1 p.m) and aluminum fine particles were mixed by mechanical milling. Mixture was heated above the melting point of polystyrene and then cooled naturally in the air. The frequency characteristics of the complex relative permeability the complex relative permittivity were calculated from values of the scattering parameters of the coaxial line loaded with a sample of a toroidal-core shape. Both the magnetization and the magnetic loss increased proportional to the volume mixing ratio of aluminum particles up to approximately 34 vol% for samples made of polystyrene particles with approximately 200 μm or 1 μm diameter. The diamagnetism was almost frequency independent and the magnetic loss decreased with increasing frequency for all samples. These results were in agreement with qualitative theoretical prediction.
- Aluminum particles
- Composite electromagnetic wave absorber
- Percolation threshold
- Polystyrene particles
- Skin effect
ASJC Scopus subject areas
- Electrical and Electronic Engineering