Chapter 17
Nanocomposites for Permanent Magnets
Isabelle de Moraes and Nora M. Dempsey
Abstract Permanent magnets are exploited in a variety of devices (e.g. motors,
generators, sensors, actuators) used in various fields of applications including transportation (e.g. (hybrid)electric vehicles), energy management (wind turbines…)
and information technology (e.g. hard disc drives). Permanent magnet research
today is concerned with improving the performance of magnets based on various
hard magnetic phases while reducing dependence on any critical materials used.
Nanocomposite magnets which combine a high coercivity hard magnetic phase with a
high magnetisation soft magnetic phase hold great potential to rise to this challenge. In
this chapter, we briefly outline the history of permanent magnets and explain the basic
physical concepts behind nanocomposite permanent magnets. We recall the metallurgical and physical vapour deposition synthesis routes used to fabricate bulk and thin
film nanocomposites, respectively. We then focus on chemical synthesis methods
which offer the possibility to produce hard and soft magnetic nanoparticles or coreshell nanoparticles that can be used as building blocks to fabricate bulk hard-soft
nanocomposites. We present three case studies concerning the fabrication and structural and magnetic characterisation of FePt-Fe 3 Pt, FePd-Fe and SmCo 5 -Fe nanocomposites. We wrap up the chapter with an outline of the challenges faced in producing
hard-soft nanocomposite magnets using chemically synthesised nanoparticles, and
an overview of the advanced magnetic characterisation tools being used to study the
complex magnetisation reversal processes at play in hard-soft nanocomposites.
I. de Moraes · N. M. Dempsey (B)
Institut Néel, CNRS and Université Grenoble Alpes, Grenoble, France
e-mail: nora.dempsey@neel.cnrs.fr
© Springer Nature Switzerland AG 2021
D. Peddis et al. (eds.), New Trends in Nanoparticle Magnetism,
Springer Series in Materials Science 308,
https://doi.org/10.1007/978-3-030-60473-8_17
403
Nanocomposites for Permanent Magnets
Isabelle de Moraes and Nora M. Dempsey
Abstract Permanent magnets are exploited in a variety of devices (e.g. motors,
generators, sensors, actuators) used in various fields of applications including transportation (e.g. (hybrid)electric vehicles), energy management (wind turbines…)
and information technology (e.g. hard disc drives). Permanent magnet research
today is concerned with improving the performance of magnets based on various
hard magnetic phases while reducing dependence on any critical materials used.
Nanocomposite magnets which combine a high coercivity hard magnetic phase with a
high magnetisation soft magnetic phase hold great potential to rise to this challenge. In
this chapter, we briefly outline the history of permanent magnets and explain the basic
physical concepts behind nanocomposite permanent magnets. We recall the metallurgical and physical vapour deposition synthesis routes used to fabricate bulk and thin
film nanocomposites, respectively. We then focus on chemical synthesis methods
which offer the possibility to produce hard and soft magnetic nanoparticles or coreshell nanoparticles that can be used as building blocks to fabricate bulk hard-soft
nanocomposites. We present three case studies concerning the fabrication and structural and magnetic characterisation of FePt-Fe 3 Pt, FePd-Fe and SmCo 5 -Fe nanocomposites. We wrap up the chapter with an outline of the challenges faced in producing
hard-soft nanocomposite magnets using chemically synthesised nanoparticles, and
an overview of the advanced magnetic characterisation tools being used to study the
complex magnetisation reversal processes at play in hard-soft nanocomposites.
I. de Moraes · N. M. Dempsey (B)
Institut Néel, CNRS and Université Grenoble Alpes, Grenoble, France
e-mail: nora.dempsey@neel.cnrs.fr
© Springer Nature Switzerland AG 2021
D. Peddis et al. (eds.), New Trends in Nanoparticle Magnetism,
Springer Series in Materials Science 308,
https://doi.org/10.1007/978-3-030-60473-8_17
403