Electromagnetic and absorbing properties of the composites based on iron, cobalt, B and rare earth Nd

Abstract

In this paper, nanocomposite FeCoB alloy with low content of Nd were prepared by rapidly quenched technology and then treated with high energy ball milling for different milling time. The XRD spectra suggests that all samples only have the single ∝-Fe phase. Calculated by Scherrer formula, the grain size decreases with increasing ball milling time. The electromagnetic (EM) properties were investigated in the frequency range of 2–18 GHz by Agilent PNA 8363B. The permeability-frequency for all ball milling samples were increased at first and then decreased, while the permittivity-frequency were remained relatively a constant. It is found that the absorbing mechanism for as spun sample is natural resonance while that of the milled samples are eddy current effect. According to the transmission line theory, the reflection loss of samples has been significantly improved in the specific frequency range. The particles milled for 4 h presented a reflection loss of −9.8 dB at 3.8 GHz. It is noted that the appropriate milling time is the key of the excellent electromagnetic wave absorption properties in C-band.