Electromagnetic wave-absorption properties of rapidly quenched of Nd–Fe–B nanocomposites with low Nd content

The electromagnetic wave-absorption properties of Nd3Fe68−xMnxCo18B11 (x=0, 1, 2) alloys obtained by rapid quenching from the melt was studied. The complex permittivity-frequency and permeability-frequency properties were determined in the microwave frequency regime of 2–18 GHz by vector network analysis. XRD spectra showed that only α-Fe diffraction peak was observed in the as-spun alloys. It is found that the acquired complex permittivity and permeability values match the microwave frequency when the 1 at% Mn content was doped. A minimum reflection loss of −6.9 dB is obtained at 2.7 GHz for composite Nd3Fe66Mn2Co18B11 with absorber thickness of 1.5 mm. The exchange interaction was attributed to the microwave absorption properties. The results suggest a new design of microwave absorbers based on electromagnetic wave-absorbing materials.