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Neodymium magnets particulars

  1. Dec 18, 2006 #1
    There are lots of patents on Neo magnets and they are difficult to sort out. Some of the patents restrict the use of the magnets that contain cobalt and/or have a tetragonal crystalline structure.
    Does someone know:

    What types of magnets contain cobalt?
    What types of magnets have a tetragonal structure?
  2. jcsd
  3. Dec 18, 2006 #2


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    Most NdFeB magnet patents are held by GE and/or Sumitomo. You should check with them.

    I expect there's a lot of literature on Co doping in the Fe site (I think it increases Tc and uniaxial anisotropy, up to some optimal doping), but know absolutely nothing about patents here.
  4. Dec 19, 2006 #3
    The Neomax (Sumitomo) and Magnequench (GM) patents do require licences for Neo magnets that contain cobalt and have tetragonal structures. I am curious if all high energy (>30MOe) and high temperature (>110C) magnets use this type of technology.
    Last edited: Dec 19, 2006
  5. Dec 27, 2006 #4
    Does anyone know who has the patents on Quadrupole Neodymium. I found a video of one on YouTube:

    You can find these magnets in particle accelerators, and they have 4 poles (Quadrupole). This one is a permanent magnet, and without the video I couldn't tell the difference between it and an ordinary bar magnet.
    Last edited by a moderator: Sep 25, 2014
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