10. Magnetic materials category
Magnetic materials basically include Ferrite and AlNiCo, Sm-Co and NdFeB.
Sm-Co and NdFeB were called rare earth permanent magnet.
At present, the magnet most widely applied are Ferrites, cause it is very cheap; the following is Nd-Fe-B magnet.
The temperature stability of AlNiCo and Sm-Co are better than NdFeB. So in some pointer instrument, military supplies and luxury goods, AlNiCo and SmCo materials are essential.
Curie temperature of Ferrites is 465℃, Nd-Fe-B is 310℃, Alnico is 800℃, Sm-Co is 700℃--800℃. we can see that temperature stability of Nd-Fe-B is the worst. but the magnetic performance is the highest, that’s why it called "magnetism king", Currently the manufacture craft of magnetic materials are sintered and bonded. bonded magnet has lower performance, because it use adhesive bonding, but with higher precision.
Contact