Effect of Nd content on natural resonance frequency and microwave permeability of Nd2Fe14B/α-Fe nanocomposites in 26.5–40 GHz frequency range

The effect of the rare earth Nd contents on the natural resonance frequency and microwave permeability of Nd2Fe14B/α-Fe nanocomposites was investigated. The NdxFe94−xB6 (x = 9.5, 10.5, 11.5) ribbons were prepared using melt-spining and annealing method. The microwave complex permeability was measured in the 26.5–40 GHz frequency range. The microwave complex permeability decreased and the resonance frequencies (fr) of NdxFe94−xB6 shifted to higher values with the increase of rare earth Nd content due to the increase of Nd2Fe14B with the large anisotropy field (HA). The Nd9.5Fe84.5B6 composite realized the optimum matching situation (RL = −8.9 dB) with thin matching thickness of 0.27 mm at 36 GHz.