Elsevier

Metal Powder Report

Volume 72, Issue 6, November–December 2017, Pages 425-429
Metal Powder Report

Special Feature
Soft magnetic composites: recent advancements in the technology

https://doi.org/10.1016/j.mprp.2016.08.003Get rights and content

Soft magnetic composites allow for revolutionized designs of electromagnetic devices to aid in improved efficiency and reduced weight and costs, without sacrificing magnetic performance. Electrically insulated core powder are formed into toroid shapes and tested for core loss and magnetic permeability, which are desired to be minimized and maximized, respectively. Ferromagnetic powder has shown the most potential as core materials, however nanocrystalline materials are highly resistive and amorphous materials have benefits of very low coercivities. Likewise, organic and inorganic coating materials have been explored for the reduction of eddy currents to improve overall core losses at higher frequencies. The balance between properties is of the utmost concern for SMC applications.

Section snippets

Processing steps

The processing methods to form SMCs often follow conventional powder metallurgy techniques, such as milling or mixing of metal powder potentially with alloying elements, compacting, curing, and secondary operations, as depicted in Fig. 2. Milling of various elemental powder allows for the development of mechanically alloyed core materials, often annealed to control grain size and increase magnetic permeability [6]. Smaller grain sizes, nominally nanocrystalline materials have very high

Material selection

By and large, selecting the proper material for any application is of the utmost importance. SMCs require materials with superb soft magnetic properties to be functional at the desired frequency and possess the mechanical integrity to be handled in a manufacturing facility and perform at high speeds. The soft magnetic properties of interest include high magnetic permeability (high magnetic saturation and low coercivity), which are obtained by the least amount of nonmagnetic inclusions. A great

Future of SMCs

SMCs require low core losses and high magnetic permeability at various frequency ranges for diverse applications such as aerospace and automobiles. The future of SMCs lies in balancing high electrical resistivity, high mechanical strength, and high magnetic performance utilizing both a core and coating material, or maybe a new class of materials. Such as an Fe–Si–Cu composition that allows for improved mechanical strength and electrical resistivity without decreasing magnetic properties greatly

Acknowledgements

The authors gratefully acknowledge support in part from the National Science Foundation under contract 1031403, and in part from the Hoeganaes Corporation.

References (53)

  • H. Shokrollahi et al.

    J. Mater. Process. Technol.

    (2007)
  • B. Slusarek et al.

    Metal Powder Rep.

    (2009)
  • W. Xu et al.

    J. Magn. Magn. Mater.

    (2015)
  • W. Ding et al.

    J. Magn. Magn. Mater.

    (2015)
  • K. Gheisari et al.

    J. Magn. Magn. Mater.

    (2008)
  • M. Lauda et al.

    J. Magn. Magn. Mater.

    (2016)
  • A.H. Taghvaei et al.

    Mater. Des.

    (2009)
  • M. Wang et al.

    J. Magn. Magn. Mater.

    (2014)
  • M.E. McHenry et al.

    Prog. Mater. Sci.

    (1999)
  • C. Oikonomou et al.

    Mater. Sci. Eng. B

    (2014)
  • G. Zhao et al.

    J. Magn. Magn. Mater.

    (2016)
  • Y. Peng et al.

    J. Magn. Magn. Mater.

    (2015)
  • M. Yaghtin et al.

    J. Alloys Compd.

    (2013)
  • S. Wu et al.

    J. Magn. Magn. Mater.

    (2012)
  • S. Wu et al.

    J. Magn. Magn. Mater.

    (2015)
  • M.A. Malik et al.

    Arab. J. Chem.

    (2012)
  • K.J. Sunday et al.

    J. Alloys Compd.

    (2015)
  • C. Wu et al.

    J. Alloys Compd.

    (2016)
  • I. Hemmati et al.

    J. Magn. Magn. Mater.

    (2006)
  • A.H. Bahrami et al.

    Powder Technol.

    (2013)
  • W.J. Yuan et al.

    J. Alloys Compd.

    (2010)
  • P. Kollár et al.

    J. Magn. Magn. Mater.

    (2014)
  • M.M. Dias et al.

    Powder Technol.

    (2013)
  • L. Svensson et al.

    J. Magn. Magn. Mater.

    (2012)
  • M. Huang et al.

    J. Alloys Compd.

    (2015)
  • M. Strecková et al.

    Mater. Lett.

    (2013)
  • Cited by (168)

    View all citing articles on Scopus
    View full text