Exchange-Coupled Nanocomposite Permanent Magnets



Exchange-coupled nanocomposite magnets are a new type of permanent magnetic materials. Large amounts of theoretical and experimental research have been carried out in the past two decades in understanding the inter-phase exchange interactions and in processing bulk nanocomposite magnets with enhanced energy products. This chapter reviews recent advancements in both the fundamental research and the materials processing technologies. Details in the new findings about the effects of soft phase properties and interface conditions on the hard/soft phase exchange interactions are presented. Various methods for characterizing the inter-phase exchange coupling are reviewed. In materials processing aspects, the development of the bottom-up approaches is discussed. Novel methodology for nanoparticle synthesis including the salt-matrix annealing and surfactant-assisted ball milling is described. Unconventional compaction techniques including warm compaction and dynamic compaction are recommended because they can be used to retain the desired nanoscale morphology for effective exchange coupling in the nanocomposites. At the end of this chapter, perspectives on fabrication of anisotropic nanocomposite magnets are given.


Exchange Coupling Nanocomposite Magnet Dynamic Compaction FePt Nanoparticles Explosive Compaction 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



First I would like to thank my former promoter and colleague Prof. D.J. Sellmyer (one of the editors of this book) who guided me to enter this research area in 1995. I would also like to thank my students, postdoctoral researchers, and collaborators who have contributed directly to the work reviewed in this chapter: H. Zeng, T. S. Vedantam, B. Altuncevahir, N. Poudyal, V. Chakka, K.E. Elkins, V. Nandwana, K.H. Chen, Z.Q. Jin, C.-b Rong, G. Chaubey, Y. Li, K. Yano, D. Li, Y. Wang, M. Yue, T. Black, Q. Zhang, D. Wu, Z.J. Guo, Y. Choi, J.S. Jiang, S.D. Bader, S. Saha, J.A. Barnard, W. Sofa, S.G. Sankar, G. Zangari, C. O’Connor, M.-h Yu, A.J. Zambano, I. Takeuchi, S.S. Yan, B.Z. Cui, K. Han, H. Garmestani, H. Schneider-Muntau, J. Crow, M. Chen, Y. Hou, S. Sun, K. Gallagher, S.-F. Cheng, J. Li, Y. Ding, Y. Liu, Y. Zhang, M.J. Kramer, C.D. Dai, N.N. Thadhani, and Z.L. Wang. This work has been supported in part by US DoD/DARPA through ARO under grant DAAD 19-03-1-0038 and DoD/MURI grant N00014-05-1-0497. Dr. V. Browning and Dr. J. Prater are highly appreciated for their long-term support to this effort.


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© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Department of PhysicsUniversity of Texas at ArlingtonArlingtonUSA

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