Effect of Sendust Particle Size on Absorption Characteristics of Composite Electromagnetic Wave Absorber
The effects of the particle size of sendust, which is an alloy of Al 5%, Si 10%, and Fe 85%, on the absorption characteristics of composite electromagnetic wave absorbers made of polystyrene resin and sendust were investigated in the frequency range from 1 to 40 GHz. The size of sendust particles was varied between approximately 5 and 20 m. A metal-backed single-layer absorber made of 20 m sendust particles absorbed more than 99% of electromagnetic wave power at frequencies above 20 GHz. Meanwhile, a composite made of 5 m particles exhibited a return loss of less than −20 dB in the frequency range of not only several GHz but also above 30 GHz. In addition, the relative complex permeability r* was shown to be controlled by adjusting the particle size of sendust, and an electromagnetic wave absorber with a flexible design was proposed.
Tadashi Takenaka, Hajime Haneda, Kazumi Kato, Masasuke Takata and Kazuo Shinozaki
K. Sakai et al., "Effect of Sendust Particle Size on Absorption Characteristics of Composite Electromagnetic Wave Absorber", Key Engineering Materials, Vols. 421-422, pp. 451-454, 2010