Microwave Absorption Properties of Fe-Based Amorphous Particles Prepared Using Ball-Milling Method

Abstract

Fe_73.5Si_13.5B₉Cu₁Nb₃ amorphous particles of varying size and shape were prepared using a simple ball-milling process. The phase structure and morphology of the particles were determined by x-ray diffraction and scanning electron microscopy, respectively. The static magnetization and electromagnetic properties of the particles were also measured. Particles that were processed by ball-milling for 35 h possessed excellent microwave-absorbing properties which present not only the widest frequency band of reflection loss (RL) at below − 20 dB over the range 10.8–12.8 GHz but also the maximum absorption peak, − 27.3 dB at a frequency of 11.6 GHz. Higher permeability and lower permittivity were obtained due to decreased particle size and formation of nanocrystalline α-Fe(Si) grains in the amorphous matrix. Particles milled for 15 h and 25 h also exhibited improved electromagnetic wave absorbing performance, with RL values of − 24.9 dB at 9.4 GHz and − 23.4 dB at 9.2 GHz, respectively, owing to the appearance of flake-shaped particles. Thus, Fe_73.5Si_13.5B₉Cu₁Nb₃ particles processed using a ball-milling process proved to be effective microwave absorbers.