Mu metal......

[beedees]

What is it? How does it work?

[lancaIV]

Mumetal(l),also called Permalloy,for example Nickel-based core !
The "net/Google:Mumetal" gives you more information !

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[gn0stik]

Perhaps that's the stuff I found inside the hard drives I've been taking apart for the magnets. I found the magnets glued to this stuff that seemed to shield the neo mag's field that was directly epoxied to it. A screw would not stick to that stuff even though the field of one is over an inch large when not attached to the mystery metal I found inside. The screw would just slide right off. It looked like steel but didn't act like it at all.

[gn0stik]

After doing a quick google search of "hard drive mu-metal shield" they are used in hard drives for magnetic shielding, and they DO shield magnetic fields. Just an FYI

The stuff in hard drives doesn't completely negate it, for obvious reasons, but the heads and the armature magnet shields are made of mu metal. That's why HDs have such powerful magnets in them, yet do not destroy the data on them.


They do not shield 100% but it is very effective, in my tests, the magnet attached to the other side of the mu metal, had the effect that If I tried to pick up something iron with it on the mu metal side it wouldn't work, but on the magnet side, it picked it up from over an inch away. However if I tried to attach another magnet to that side the shielding was not strong enough to block that. It would still pick up another magnet. I have a feeling, If I had another piece to sandwich onto the back it wouldnt' have even picked that up.

too bad femm doesn't have the ability to add this stuff to it to simulate the effect on fields.

Regards.

[lancaIV]

www.northwestmagnet.com/permanent-magnets-ceramic-assemblies.html

Its about magnet field force shielding and concentrating/
amplifying !

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