Electromagnetic wave absorption properties of nanocomposite powders derived from intermetallic compounds and amorphous carbon

Nanocomposite materials consisting of Y₂Fe₁₇ and amorphous carbon (a-C) were prepared by a mechanical grinding method. Mean crystalline size of the Y₂Fe₁₇ particles in the nanocomposite materials was evaluated to be 20 nm from the line broadening of diffraction peaks. Complex permittivity, permeability and electromagnetic wave absorption properties of resin compact containing 75 wt.% Y₂Fe ₁₇/a-C powders showed the good electromagnetic wave absorption properties of the minimum reflection loss (RL) value of - 48 dB at 17 GHz with a matching thickness of a 1.3 mm because the eddy current loss was effectively suppressed by increasing the electric resistance for Y₂Fe ₁₇ particle with hybridization with a-C as an insulator.