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Close proximity magnets and demagnetism

Close proximity magnets and demagnetism

Close proximity magnets and demagnetism

Hi all,

My first post here.

I am looking to use two strong magnets, to repel each other, in close proximity.

Neodymium, same strength, same dimensions

They will not touch, but over time will the close proximity demagnetise them?

Heat is no issue and they will not be hammered in anyway, one will revolve (but not change position), while the other stays static

Any help would be greatly appreciated

Kindest Regards


RE: Close proximity magnets and demagnetism

They will demag some, or you wouldn't end up with any force.
Will the gap between them fluctuate?  if so then you will have a bit more demag over time. Even slight changes in temperature will cause significant demag.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

RE: Close proximity magnets and demagnetism

Yes the distance between will fluctuate, around 1mm or so. And spin would be around 100 rpm

How long can i expect them to take to demagnatise? hours? days? years?

Heat change would be around 2 or 3 degrees

I am looking at magnets with around a 20kg pull



RE: Close proximity magnets and demagnetism

Bump it up

Any more thoughts on how long they would last?



RE: Close proximity magnets and demagnetism

To keep things simple, under the conditions you intend to use Rare Earth Magnets, they will not demagnitize.

RE: Close proximity magnets and demagnetism


I keep the same idea with SREID, if the Magnets has the same magnetic properties, it is hard to be demagnitized .

RE: Close proximity magnets and demagnetism

If you are using rare earth material, the demagnizing level is very small according to your discribe. In the production, sometime we do "aging process" to the magnets, the magnetic property will be reduced by 3-5%, and after that, the magnets will be stablized. So i think your case will be less than this.

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