What makes ferromagnetic material better for magnetic applications?

[physicist888]

magnetic matter??

hi all
how could we know that this magnetic matter is better than the other?
what should be the structure inside a matter to have the best magnetic matter?
maybe best magnetic matter is the ferromagnetic ??

 

[olgranpappy]

ferromagnets are good magnets, elemental examples being iron, nickel, and cobalt.

Samarium Cobalt makes a darn fine magnet:

http://en.wikipedia.org/wiki/Samarium-cobalt_magnet

I guess the "best" kind depends on what you want the magnet for. More on magnets in a pretty good book called "Solid State Magnetism" by Crangle.