Electromagnetic wave absorbing properties and hyperfine interactions of Fe-Cu-Nb-Si-B nanocomposites

• Published in: Chinese physics B 2014-08, Vol.23 (8), p.50-54
• Main Authors: Han, Man-Gui, Guo, Wei, Wu, Yan-Hui, Liu, Min, Hadimani, Magundappa L.
• Format: Article
• Language: English
• Subjects: Atomic beam spectroscopy; Ferromagnetic phases; Flakes; Microwaves; Nanocomposites; Nanostructure; Permeability; Two phase; 微波介电常数; 微波吸收性能; 电磁波吸收; 纳米复合材料; 超精细相互作用; 铁磁相; 高分辨透射电子显微镜
• ISSN: 1674-1056; 2058-3834; 1741-4199
• DOI: 10.1088/1674-1056/23/8/083301

The Fe-Cu-Nb-Si-B alloy nanocomposite containing two ferromagnetic phases （amorphous phase and nanophase phase） is obtained by properly annealing the as-prepared alloys. High resolution transmission electron microscopy （HR- TEM） images show the coexistence of these two phases. It is found that Fe-Si nanograins are surrounded by the retained amorphous ferromagnetic phase. Mossbauer spectroscopy measurements show that the nanophase is the D03-type Fe- Si phase, which is employed to find the atomic fractions of resonant 57Fe atoms in these two phases. The microwave permittivity and permeability spectra of Fe-Cu-Nb-Si-B nanocomposite are measured in the frequency range of 0.5 GHz- 10 GHz. Large relative microwave permeability values are obtained. The results show that the absorber containing the nanocomposite flakes with a volume fraction of 28.59% exhibits good microwave absorption properties. The reflection loss of the absorber is less than -10 dB in a frequency band of 1.93 GHz-3.20 GHz.