Effects of Co Element on the Structure, Magnetic, and Microwave Absorption Properties of La-Fe-B Alloys

  • Pengcheng Yang
  • Chuang Tian
  • Qingrong YaoEmail author
Original Paper


In order to understand the intrinsic properties of high abundance permanent magnet materials, effects of Co element on the structure, magnetic, and microwave absorption properties of La12.5(Fe1-xCox)81.3B6.2 alloys have been investigated with x = 0, 0.1, 0.2, 0.3. The X-ray diffraction results revealed that compounds of La12.5(Fe1-xCox)81.3B6.2 crystallized the Nd2Fe14B-type structure with the space group P42/mnm. The saturation magnetization of the powders increases with the Co content increasing, 97.7 emu/g for x = 0.3. The minimum absorption peak value of La12.5(Fe1-xCox)81.3B6.2 alloy reaches about − 18.69 dB at 10.56 GHz with the matching thickness of 2.5 mm.


Phase structure Magnetic properties Rare earths Microwave absorbing properties 


Funding Information

This work was financially supported by the National Natural Science Foundations of China (No. 51871066, No. 51761007, and No. 2016YFB0700901) and the Guangxi Natural Science Foundation (No. 2016GXNSFGA38001).


  1. 1.
    Hu, Z.H., Qu, H.J., Zhao, J.Q., et al.: Effect of sintering process on the magnetic and mechanical properties of sintered Nd-Fe-B magnets. J. Magn. Magn. Mater. 368, 54 (2014)ADSCrossRefGoogle Scholar
  2. 2.
    Sugimoto, S.: Current status and recent topics of rare-earth permanent magnets. J. Phys. D. Appl. Phys. 44, 111 (2011)CrossRefGoogle Scholar
  3. 3.
    Gutfleisch, O., Willard, M.A., Bruck, E., Chen, C.H., Shankar, S.G., Liu, J.P.: Magnetic materials and devices for the 21st century: stronger, lighter, and more energy efficient. Adv. Mater. 23, 821 (2011)CrossRefGoogle Scholar
  4. 4.
    Woodcock, T.G., Zhang, Y., Hrkac, G., et al.: Understanding the microstructure and coercivity of high performance NdFeB-based magnets. Scr. Mater. 67, 537 (2012)CrossRefGoogle Scholar
  5. 5.
    Alam, A., Khan, M., Mccallum, R.W., et al.: Site-preference and valency for rare-earth sites in (R-Ce)2Fe14B magnets[J]. Appl. Phys. Lett. 102, 4176 (2013)CrossRefGoogle Scholar
  6. 6.
    Susner, M.A., Conner, B.S., Saparov, B.I., et al.: Growth and characterization of Ce- substituted Nd2Fe14B single crystals. J. Magn. Magn. Mater. 434, (2015)Google Scholar
  7. 7.
    Yan, C., Guo, S., Chen, L., et al.: Enhanced temperature stability of coercivity in sintered permanent magnet by substitution of Ce for didymium. IEEE T. Magn. 52, 1 (2016)ADSGoogle Scholar
  8. 8.
    Fan, X., Shuai, G., Kan, C., et al.: Tuning Ce distribution for high performanced Nd-Ce-Fe-B sintered magnets. J. Magn. Magn. Mater. 394, 419 (2016)Google Scholar
  9. 9.
    Zhou, T.D., Liang, D.F., Deng, L.J., et al.: Electron structure and microwave absorbing ability of flaky FeSiAl powders. J. Mater. Sci. Technol. 27, 170 (2011)CrossRefGoogle Scholar
  10. 10.
    Wei, L., Che, R., Jiang, Y., et al.: Study on preparation and microwave absorption property of the core-nanoshell composite materials doped with La. J. Environ. Sci. 25, 27 (2013)CrossRefGoogle Scholar
  11. 11.
    Xie, W., Cheng, H.F., Chu, Z.Y., et al.: Comparison of hollow-porous and solid carbon fibers as microwave sbsorbents[J]. Adv. Mater. Res. 7, 150 (2011)Google Scholar
  12. 12.
    Zhang, X.F., Zhang, L.L., Li, Z.B., et al.: Variation of coercivity with Ce content in (Pr, Nd, Ce)2Fe14B sintered magnets. AIP Adv. 7, 056228 (2017)ADSCrossRefGoogle Scholar
  13. 13.
    Nakayama, T.: Nd-Fe-B anisotropic magnet powders produced by the HDDR process. J. Alloys Compd. 193, 259 (1993)CrossRefGoogle Scholar
  14. 14.
    Pathak, A.K., Khan, M., Gschneidner, K.A., et al.: Cerium: an unlikely replacement of dysprosium in high performance Nd-Fe-B permanent magnets. Adv. Mater. 27, 2663 (2015)CrossRefGoogle Scholar
  15. 15.
    Susner, M.A., Conner, B.S., Saparov, B.I., et al.: Growth and characterization of Ce- substituted Nd2Fe14B single crystals. J. Magn. Magn. Mater. 434, (2015)Google Scholar
  16. 16.
    Ling, C., Cao, X., Shuai, G., et al.: Coercivity enhancement of Dy-free sintered Nd–Fe–B magnets by grain refinement and induction heat treatment. IEEE T. Magn. 51, 1 (2015)Google Scholar
  17. 17.
    Xu, Y., Yao, Q., Yang, P., et al.: The effects of La doping on the crystal structure, magnetic, and microwave absorption properties of Nd2Fe14B compound. J. Supercond. Nov. Magn. 1, (2018)Google Scholar
  18. 18.
    Yao, Q., Shen, Y., Yang, P., et al.: Crystal structure and phase relations of Pr2Fe14B-La2Fe14B system. J. Rare Earths. 34, 1121 (2016)CrossRefGoogle Scholar
  19. 19.
    Arrhenius, G.: X-ray diffraction procedures for polycrystalline and amorphous materials. J. Chem. Educ. 32, (1955)ADSCrossRefGoogle Scholar
  20. 20.
    Zhang, M., Li, Z., Shen, B., et al.: Permanent magnetic properties of rapidly quenched (La, Ce) 2Fe14B nanomaterials based on La–Ce mischmetal. J. Alloys Compd. 144, (2015)Google Scholar
  21. 21.
    Shoemaker, C.B., Shoemaker, D.P., Fruchart, R.: The structure of a new magnetic phase related to the sigma phase: iron neodymium boride Nd2Fe14B. Acta Crystallogr. C. 40, 1665 (1984)CrossRefGoogle Scholar
  22. 22.
    Slater, J.C.: Atomic radii in crystals. J. Chem. Phys. 41, 3199 (1964)ADSCrossRefGoogle Scholar
  23. 23.
    Matsuura, Y., Hirosawa, S., Yamamoto, H., et al.: Magnetic properties of the Nd2(Fe1-xCox)14B system. Appl. Phys. Lett. 46, 308 (1985)ADSCrossRefGoogle Scholar
  24. 24.
    Liu, Z., Lin, W.C., Shih, C.W., et al.: Effect of Co addition on the microstructure and magnetic properties of Nd9.5Febal.CoxNb2.5Zr0.5B15 (x = 0, 10, 20) bulk magnets. J. Alloys Compd. 538, (2012)Google Scholar
  25. 25.
    Michielssen, E., Sajer, J.M., et al.: Design of lightweight, broad-band microwave absorbers using genetic algorithms. IEEE T. Microw. Theory. 41, 1024 (1993)CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.School of Materials Science and EngineeringGuilin University of Electronic TechnologyGuilinPeople’s Republic of China
  2. 2.Guangxi Key Laboratory of Information MaterialsGuilin University of Electronic TechnologyGuilinPeople’s Republic of China

Personalised recommendations