Effect of Ti Content on Microwave Absorbing Properties of Nd-Fe Alloys

Abstract:

The Nd_7.69Fe_92.31-xTi_x (x = 0, 4, 8, 12) alloy were prepared by arc smelting and high energy ball milling method. The morphology and phase structure of the powders were analyzed by Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and the effect of the Ti content on microwave absorbing properties of the powders were measured by a vector network analyzer (VNA). The results reveal that the samples mainly consisted of Nd₂Fe₁₇ and α-Fe crystal structure. The minimum absorption peak frequency shifts to lower frequency region firstly and then shifts to higher frequency region with the increasing amount of Ti content. The minimum reflection loss of Nd_7.69Fe_84.31Ti₈ powder is-31.35 dB and the bandwidth of R < -5 dB reach 3.6 GHz when the coating thickness is 2.0 mm. With the increasing of the coating thickness, the minimum reflectivity peak value of the Nd_7.69Fe_84.31Ti₈ moves to lower frequency region and the minimum reflection loss increase firstly and then decrease. And the minimum reflection value of Nd_7.69Fe_84.31Ti₈ alloy can reach to-38.74 dB (microwave absorption rate 99.99%) at 5.68 GHz, and the bandwidth of R < -10 dB reach 1.12 GHz with the best matching thickness of 2.2 mm.

• Periodical: Key Engineering Materials (Volume 727)
• Pages: 117-123
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.727.117
• Online since: January 2017
• Authors: Jia Liang Luo, Shun Kang Pan*, Zhen Zhong Wang, Zi Qiang Qiao, Li Chun Cheng
• Keywords: Crystal Structure, High Energy Ball Milling, Microwave Absorbing Properties, Phase Structure

References

[1] S.H. Liu, J.M. Liu, X.L. Long, Y.P. Duan. Electromagnetic wave shielding and absorbing materials. M. Chemical industry press. (2013)49-60.

[2] J.H. Liu, T.Y. Ma, H. Tong. Electromagnetic wave absorption properties of flaky Fe-Ti-Si-Al nanocrystalline composites. J. Magn. Magn. Mater. 322 (2010) 940-944.

DOI: 10.1016/j.jmmm.2009.11.028

[3] S.G. Zhang, H.G. Zhu, J.J. Tian. Electromagnetic and microwave absorbing properties of FeCoB powder. Rare Met. 32 (2013) 402-407.

DOI: 10.1007/s12598-013-0115-0

[4] M.S. Kim, E.H. Min, J.G. Koh. Comparison of the effects of particle shape on thin FeSiCr electromagnetic wave absorber. J. Magn. Magn. Mater. 321 (2009) 581-585.

DOI: 10.1016/j.jmmm.2008.09.033

[5] X.L. Shi, M.S. Cao, J. Yuan, X.Y. Fang, Dual nonlinear dielectric resonance and nesting microwave absorption peaks of hollow cobalt nanochains composites with negative permeability. Appl. Phys. Lett. 95 (2009) 163108.

DOI: 10.1063/1.3250170

[6] T.D. Zhou, D.F. Liang, L.J. Deng, D.C. Luan. Electron structure and microwave absorbing ability of flaky FeSiAl powders. J. Mater. Sci. Technol. 27 (2011) 170.

DOI: 10.1016/s1005-0302(11)60044-3

[7] K.S. Lee, Y.C. Yun, I.B. Jeong, S.S. Kim. Microwave absorbing properties of flaky Fe-Si-Al alloy powder -rubber composites. J. Materials Science Forum. (2007) 1465-1468.

[8] H. Tian, H.T. Liu, H.F. Cheng, A high-temperature radar absorbing structure: design, fabrication, and characterization. Compos. Sci. Technol. 90 (2014) 202–208.

DOI: 10.1016/j.compscitech.2013.11.013

[9] X. Wang, R.Z. Gong, H. Luo, Z.K. Feng. Microwave properties of surface modified Fe-Co-Zr alloy flakes with mechanochemically synthesized polystyrene. J. Alloy. Compd. 480 (2009) 761–764.

DOI: 10.1016/j.jallcom.2009.02.037

[10] Y.K. Sun. Metallic Soft Magnetic Materials and Its Application. M. Metallurgical Industry Press Chin. 24 (1986) 6-59.

[11] J.L. Xiong, S.K. Pan, L.C. Cheng, Q.R. Rao, G.H. Rao, G.S. Xie. Effects of Ti doping on structure and microwave absorption properties of Pr2Fe17 alloy. J. J. Mater. Sci: Mater. Electron. 26 (2015) 7020-7025.

DOI: 10.1007/s10854-015-3322-7

[12] K. Yanagimoto, K. Majima, S. Sunada. Effect of powder compositions on GHz microwave absorption of EM absorbing sheets. J. Jpn. Soc. Powder Metall. 51 (2004) 293-296.

DOI: 10.2497/jjspm.51.293

[13] W.Q. Zhang, S.W. Bie, H.C. Chen, Y. Lu, J.J. Jiang. Electromagnetic and microwave absorption properties of carbonyl iron/MnO2 composite. J. Magn. Magn. Mater. (2014) 1-4.

[14] S.B. Liao. Ferromagnetic (PartII). M. Science Press Beijing. (1988) 3-88.

[15] S.B. Liao, G.J. Yin. The absorption and reflection of absorbing material on electromagnetic wave [J]. Aerospace Materials and Technology, 2 (1992) 16–20.

[16] I. Kong, S.H. Ahmad, M.H. Abdullah, D. Hui, A.N. Yusoff, D. Puryanti. Microwave absorbing properties of magnetite-thermoplastic natural rubber nanocomposites. J. Magn. Magn. Mater. 322 (2010) 3401-3409.

DOI: 10.1016/j.jmmm.2010.06.036

[17] H.B. Yi. Microwave absorbing properties planar rare earth intermetallic compounds powders/paraffin composites. D. Lanzhou University. (2009) 40-46.