Physics Van 3-site Navigational Menu

Physics Van Navigational Menu

Q & A: pure metal magnets? or alloys?

Learn more physics!

Most recent answer: 07/25/2016
Q:
Is it possible/feasible to make magnets of pure cobalt, nickel and all other ferromagnetic materials? All magnets I encounter seem to be alloys, and I don't think I've ever seen a pure cobalt magnet.
- Laura (age 18)
Minneapolis, MN
A:

Great question! There's a problem making permanent magnets from pure magnetic metals. They form great magnetic domains, but the magnetic energy is lowered when the domains point different directions, leaving very little net magnetism.To make a permanent magnet, you need some way to trap the magnetic domains so that the magnetism can't just rotate to the lowest energy state. The non-magnetic atoms actually help keep the magnetism from changing by helping trap domain walls so that the boundaries between the domains stay fixed.

Mike W.


(published on 07/25/2016)

Follow-up on this answer.