Electromagnetic and Microwave Absorption Properties of Carbonyl-Iron/Fe91Si9 Composites in Gigahertz Range
- 1
- 2
- 3
- 4
- 5
Abstract
Carbonyl-iron/Fe91Si9 composites for thin microwave absorbers were firstly prepared by a simple blending technique. The patterns of carbonyl-iron and Fe91Si9 were characterized by scanning electron microscope (SEM). The complex permittivity, permeability and microwave absorption properties of the composites were studied in the frequency range of 2 - 7GHz by a HP8720B vector network analyzer. Complex permittivity and permeability decrease gradually with increasing weight percentage of Fe91Si9 in the composites, the variation of permittivity was very large but the variation of permeability was very small. The composites exhibited excellent microwave absorption properties with increasing Fe91Si9 content. The reflection loss (RL) values less than –20 dB were obtained in the 3.7 - 6.7 GHz frequency range for the paraffin matrix composites with 80 wt% carbonyl-iron/Fe91Si9 powders (weight ratio of carbonyl-iron to Fe91Si9 was 1:1), with thickness of 4.0 - 2.4 mm, respectively. The optimal RL of –45 dB was observed at 5.2 GHz with a matching thickness (dm) of 3.0 mm. The excellent microwave absorption properties were attributed to a better electromagnetic impedance match and a higher electric resistivity.
- L. G. Yan, J. B. Wang, Y. Z. Ye, Z. T. Hao, Q. F. Liu and F. S. Li, “Broadband and Thin Microwave Absorbers of Nickel-Znic Ferrite/Carbonyl-Iron Composites,” Journal of Alloys and Compounds, Vol. 487, No. 1-2, August 2009, pp. 708-711. doi:10.1016/j.jallcom.2009.08.051
- T. Kondo, T. Aoki, K. Asano and S. Yoshikado, “Fabrication of the Composites Electromagnetic Wave Absorbers,” International Symposium on Electromagnetic Compatibility, Vol. 19, Tokyo, June 1999, pp. 397-400.
- F. S. Wen, W. L. Zuo, H. B. Yi, N. Wang, L. Qiao and F. S. Li, “Microwave-Absorbing Properties of Shape-Optimized Carbonyl Iron Particles with Maximum Microwave Permeability,” Physica B, Vol. 404, No. 20, October 2009, pp. 3567-3570. doi:10.1016/j.physb.2009.06.001
- J. C. Aphesteguy, A. Damiani, D. DiGiovanni and S. E. Jacobo, “Microwave-Absorbing Characteristics of Epoxy Resin Composites Containing Nanoparticles of NiZn- and NiCuZn-Ferrites,” Physica B, Vol. 404, No. 18, October 2009, pp. 2713-2716. doi:10.1016/j.physb.2009.06.065
- Y. X. Gong, L. Zhen, J. T. Jiang, C. Y. Xu and W. Z. Shao, “Preparation of CoFe Alloy Nanoparticles with Tunable Electromagnetic Wave Absorption Performance,” Journal of Magnetism and Magnetic Materials, Vol. 321, No. 22, November 2009, pp. 3702-3705. doi:10.1016/j.jmmm.2009.07.019
- Y. L. Cheng, J. M. Dai, D. J. Wu and Y. P. Sun, “Electromagnetic and Microwave Absorption Properties of Carbonyl-Iron/La0.6Sr0.4MnO3 Composites,” Journal of Magnetism and Magnetic Materials, Vol. 322, No. 1, January 2010, pp. 97-101. doi:10.1016/j.jmmm.2009.08.037
- J. R. Liu, M. Itoh and K. Machida, “GHz Range Absorption Properties of α-Fe/Y2O3 Nanocomposites Prepared by Melt-Spun Technique,” Chemistry Letters, Vol. 32, No. 4, 2003, pp. 394-396. doi:10.1246/cl.2003.394
- X. G. Liu, D. Y. Geng, H. Meng, P. J. Shang and Z. D. Zhang, “Microwave-Absorption of ZnO-Coated Iron Nanocapsules,” Applied Physics Letters, Vol. 92, No. 17, April 2008, pp. 173117-173117-3. doi:10.1063/1.2919098
- X. L. Dong, X. F. Zhang, H. Huang and F. Zuo, “Enhanced Microwave Absorption in Ni/Polyaniline Nanocomposites by Dual Dielectric Relaxations,” Applied Physics Letters, Vol. 92, No. 1, January 2008, pp. 013127- 013127-3. doi:10.1063/1.2830995
- X. G. Liu, D. Y. Geng, H. Meng, W. B. Cui, F. Yang, D. J. Kang and Z. D. Zhang, “Microwave Absorption Properties of FCC-Co/Al2O3 and FCC-Co/Y2O3 Nanocapsules,” Solid State Communication, Vol. 149, No. 1-2, January 2009, pp. 64-67. doi:10.1016/j.ssc.2008.10.015