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Indexed by:Journal Papers

Date of Publication:2020-03-01

Journal:JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

Included Journals:EI、SCIE

Volume:497

ISSN No.:0304-8853

Key Words:Fe-based nanocrystalline alloys; Ferromagnetic powders; Electromagnetic properties; Electromagnetic wave absorption; Ball milling

Abstract:Fe80.7Si4B13Cu2.3 nanocrystalline soft magnetic alloy powders with outstanding electromagnetic wave absorption properties in X-band (8-12 GHz) have been successfully synthesized by a ball-milling method. As milling time increases from 40 to 160 h, the mean particle size of the near spherical powders with a bcc-Fe nanocrys-talline/amorphous composite structure decreases from 9 to 6 while the average nanocry-stalline grain size stabilizes at around 10 nm. The alloy powders possess high saturation magnetization of 178.2-183.4 emu/g. The alloy powders/paraffin (3:1 in mass ratio) composites exhibit real permeability and permittivity of 2.18-2.42 and 7.3-9.7 at 2 GHz, respectively, and imaginary permeability of 0.68-0.77 at resonance frequencies of around 12.5 GHz. The composites with thicknesses of 2.1-2.3 mm exhibit large reflection losses (RL) of -39.1 to - 50.5 dB with effective absorption bandwidths (RL < - 10 dB) of 4.5-5.0 GHz covering the X-band. The excellent absorption properties are benefited from the high permeability and matchable permittivity of the nanocrystalline alloy powders in GHz range.