Magnetizing A Steel Bolt
Entry posted by Kzoppistan
3,269 views
So... I did this today.
The reason a coil of wire can create a magnet out of a piece of ferrous material, such as this steel bolt in my picture, is because of a very interesting affect of elctro-magnetic fields. When electricity flows through a wire it generates a magnetic field that travels in a circle along the diameter of the wire. When such a wire is twisted into a helix shaped coil, the fields overlap. Now a meta-field travels in one direction along the inner part of the coil and travels around the edge in the opposite direction on the outer side of
the coil.
Thus, the field which travels through anything else in its path draws the alignment of the spin state of the electrons within atoms parallel with the path of the magnetic current. This amplifies the
dipole attribute of the ferrous molecules, since, in effect, developing a strong attraction to the opposite charge (by the combined alignment of the electrons,) the material becomes a magnet itself. Even with the electrical force removed, the electrons remain in their "combed" state until changed by a stronger field or heated.
That is a simplified model, the particulars behind why some materials, like iron, or nickel, develop and retain strong magnetic forces is of course a bit more complex, involving crystaline lattices and the atomic energy exchange model, but none-the-less a fascinating look at a small part under the quantum theory umbrella.
2 Comments
Recommended Comments