Microwave reflection properties of planar anisotropy Fe₅₀Ni₅₀ powder/paraffin composites

The reflection properties of planar anisotropy Fe₅₀Ni₅₀ powder/paraffin composites have been studied in the microwave frequency range. The permeability of Fe₅₀Ni₅₀ powder/paraffin composites is greatly enhanced by introducing the planar anisotropy, and can be further enhanced by using a rotational orientation method. The complex permeability can be considered as the superposition of two types of magnetic resonance. The resonance peak at high frequency is attributed to the natural resonance, while the peak at low frequency is attributed to the domain-wall resonance. The simulated results of the microwave reflectivity show that the matching thickness, peak frequency, permeability, and permittivity are closely related to the quarter wavelength matching condition. The Fe₅₀Ni₅₀ powder/paraffin composites can be attractive candidates for thinner microwave absorbers in the L-band (1-2 GHz).