Terry Pinnell
Guest
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Posted:
Fri Feb 11, 2005 1:36 pm Post subject:
Determining a magnet's life? |
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I've been pleased with this pair of 'magnetic' sandals I bought a
couple of summers ago. I just slip a foot into one, shake it a bit if
necessary, and the pair of magnets mounted in its strap automatically
fastens it securely with a sharp snap.
Anyone know the approximate 'life' of such magnets? Are we talking
decades, centuries or millennia?
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Terry Pinnell
Hobbyist, West Sussex, UK
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Robert Baer
Guest
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Posted:
Fri Feb 11, 2005 2:09 pm Post subject:
Re: Determining a magnet's life? |
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Terry Pinnell wrote:
| Quote: |
I've been pleased with this pair of 'magnetic' sandals I bought a
couple of summers ago. I just slip a foot into one, shake it a bit if
necessary, and the pair of magnets mounted in its strap automatically
fastens it securely with a sharp snap.
Anyone know the approximate 'life' of such magnets? Are we talking
decades, centuries or millennia?
--
Terry Pinnell
Hobbyist, West Sussex, UK
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Depends on the formulation.
Older ("first" generation) Alnicos were a bit "soft" and certain
storage conditions could make them lose some of their magnetization in a
few years.
AFAIK all new Alnicos and rare-earth types will last until they get
heated to or above their Curie point.
The "plastic" magnets are very wimpy and canot be trusted... |
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