Comparison of the Magnetic and Absorption Properties of Flaky Super Sendust and Sendust Alloys

Abstract

Super Sendust and Sendust alloy powders were ball-milled for the same time to produce flakes and their static and dynamic magnetic properties were determined. The average size of flaky Super Sendust alloy particles was approximately 45.25 μm; the average size of Sendust alloy flakes was 40 μm. Fe–Si–Al–Ni flaky particle composites have better electromagnetic properties than Fe–Si–Al flaky particles; they have lower complex permittivity and a permeability that is approximately 1.5 times the permeability of Fe–Si–Al composites. Fe–Si–Al–Ni particles also have higher resonance than Fe–Si–Al composites, which contributes to a wider applied frequency band. The calculated reflection loss shows that the microwave-absorption performance of Fe–Si–Al–Ni composites exceeds that of Fe–Si–Al. In addition, the Fe–Si–Al–Ni composite’s absorbing band of the reflection loss below −5 dB can cover both the L-band and S-band for an absorber thickness of 2.3 mm; this is three times as wide as that of the Fe–Si–Al composite.