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Can old neodymium magnets be recycled?

  1. Feb 15, 2013 #1
    Can old neodymium magnets be crushed to a powder and re-sintered into new shapes?
  2. jcsd
  3. Feb 15, 2013 #2

    Simon Bridge

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    Don't see why not - by some process. The real question is: "is it cost effective to do so?"
  4. Feb 16, 2013 #3
    Sure. Question is about goal and amounts.

    "Crashing" has meaning if only you can't buy thin NdFeB powder.

    It's not brittle enough for direct crushing.
    Grinding solid magnet will consume a lot of abrasives, need in-liquid grinding or inert atmosphere to avoid burning, will complicate sintering due to a bigger fragment sizes, and product will be more porous than original.
    Last edited: Feb 17, 2013
  5. Feb 17, 2013 #4
    Thank You for responding.

    With China restricting export of neodymium ore, I was wondering if recycling old magnets offered an opportunity.

    Could they be melted and recast?


  6. Feb 17, 2013 #5
    Yes, it can be melted. But I'm not sure about casting idea.

    Sintering is not only about process simplification, there is some meaning to make it ceramic.
    Otherwise, why they first melt this, disperse to the powder, and later sintering

    How neodymium magnets are made
  7. Feb 18, 2013 #6
    Thank you Graniar.

    I enjoyed the link.

    By the way... I would like to know what keeps the hydrogen from igniting when

    metals are smelted in a hydrogen atmosphere.



  8. Feb 18, 2013 #7


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    Ignite with what? There is no oxygen to react with.
    React with the metals? Might depend on the metals.
  9. Feb 19, 2013 #8
    How stupid of me.

    I forgot that without oxygen, hydrogen won't burn.

    Sorry to waste your time.

  10. Mar 2, 2013 #9
    There is some research done on that. Here's an example


    Scientists at the U.S. Department of Energy's (DOE) Ames Laboratory are working to more effectively remove the neodymium, a rare earth element, from the mix of other materials in a magnet. Initial results show recycled materials maintain the properties that make rare-earth magnets useful.
    [more at the link]
  11. Mar 12, 2013 #10
    Very Interesting!
    Thank You SredniVashtar
  12. Mar 12, 2013 #11
    nice. seems like this could really help out the case for electric cars.
    although recycling lithium batteries might be even more important.
  13. Mar 13, 2013 #12
    I think it does be possible.
    But you can not get same strong magnet.
    The property will be much weaker.
  14. Mar 13, 2013 #13
    for old neodymium magnets, it's useful for rare earth element recovery
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