Complex permeability and microwave absorption properties of Y2Fe17 micropowders with planar anisotropy

Planar anisotropy Y2Fe17 powders were fabricated by rapid quenching and ball-milling techniques. The frequency dependence of complex permeability and permittivity of paraffin composites with 35 vol% Y2Fe17 powders have been investigated in the frequency range 0.1-10 GHz. The oriented composite shows a dramatic increase in permeability and a remarkable decrease in the matching thickness. The minimum reflection losses of unoriented Y2Fe17 composite and oriented Y2Fe17 composite were -48 dB at 2.34 GHz and -59 dB at 3.4 GHz, and the corresponding thicknesses were only 3.9 mm and 2.3 mm, respectively. Otherwise, the product of the static permeability and the resonance frequency for the oriented Y2Fe17 compound is 91.6 GHz, which is much higher than the value of 15.3 GHz calculated by Snoek's limit equation. Hence, the Y2Fe17 composite, with the specific property of the planar anisotropy, has great potential applications in the field of high-frequency microwave absorption.