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Science popularization of high temperature resistant magnets

The science popularization content of high temperature resistant magnet is as follows: magnetic
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Application of powerful NdFeB magnets in various fields

For a long time, the use of NdFeB magnets is very common. With the change of time
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How to distinguish the magnetic force of a magnet

Magnet is a very common thing in our life, but do you know how to distinguish the same size of magnet?
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