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Helmholtz coil with a ferrous core

  1. Apr 12, 2007 #1
    Dear all,
    I know that I can create a uniform field using the design of a Helmholtz coil with an air-core. However, if I use a ferrous core like iron, will I still be able to create a uniform field under the same conditions? Also, how is the equation for the magnetic field, B, changed when I add a ferrous core to the center of a Helmholtz coil?

    Thanks in advance,
    Mike
     
  2. jcsd
  3. Apr 12, 2007 #2

    marcusl

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    Are you trying to generate a uniform field inside the object?
     
  4. Apr 12, 2007 #3
    No. I am trying to create a uniform field between a pair of electromagnets just like the field inbetween any pair of helmholtz coils. Thanks.
     
  5. Apr 12, 2007 #4

    marcusl

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    This type of magnet used to be universally used for NMR, and can still be purchased, e.g.
    http://www.walkerldjscientific.com/Products/Product_Lines/Electromagnetics/electromagnetics.html"

    The iron yoke concentrates all of the return flux lines, dramatically increasing the field strength in the useful region, and the two poles concentrate the flux even further. To design a high quality magnet takes more knowledge of electromagnetism and materials than can be provided in a post. Homogeneity depends critically on the size and shape of the pole pieces, and how close to saturation magnetization the iron is, for instance. Suggest you get a copy of a text like Reitz and Milford, Foundations of Electromagnetism, and do some background study. Then take a look online at sites like
    http://www.geocities.com/CapeCanaveral/2404/Elect67.htm"

    Of course if you aren't too concerned about homogeneity, field strength, electrical efficiency, etc., you can just fool around and see what results.
     
    Last edited by a moderator: Apr 22, 2017
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