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Ferromagnetism is a property of certain materials (such as iron) that results in a significant, observable magnetic permeability, and in many cases, a significant magnetic coercivity, allowing the material to form a permanent magnet. Ferromagnetic materials are noticeably attracted to a magnet, which is a consequence of their substantial ...
The above describes magnetic domain structure in a perfect crystal lattice, such as would be found in a single crystal of iron. However most magnetic materials are polycrystalline, composed of microscopic crystalline grains. These grains are not the same as domains. Each grain is a little crystal, with the crystal lattices of separate grains ...
Demagnetizing a magnet is also possible. Only a few substances are ferromagnetic; the most common ones are iron, cobalt, nickel, and their alloys. All substances exhibit some type of magnetism. Magnetic materials are classified according to their bulk susceptibility. [1]
Magnetic properties of an alloy are highly dependent not only on the composition but also on heat treatment and mechanical processing. Magnetic alloys have become common, especially in the form of steel (iron and carbon), alnico (iron, nickel, cobalt, and aluminum ), and permalloy (iron and nickel).
Magnets can be used in scrap and salvage operations to separate magnetic metals (iron, cobalt, and nickel) from non-magnetic metals (aluminum, non-ferrous alloys, etc.). The same idea can be used in the so-called "magnet test", in which a car chassis is inspected with a magnet to detect areas repaired using fiberglass or plastic putty.
[7] [8] With the exception of extremely rare native iron deposits, it is the most magnetic of all the naturally occurring minerals on Earth. [7] [9] Naturally magnetized pieces of magnetite, called lodestone, will attract small pieces of iron, which is how ancient peoples first discovered the property of magnetism. [10]
It was found experimentally to be diamagnetic. Deoxy-hemoglobin is generally accepted to be a complex of iron in the +2 oxidation state, that is a d 6 system with a high-spin magnetic moment near to the spin-only value of 4.9 μ B. It was proposed that the iron is oxidized and the oxygen reduced to superoxide.
In this model, a magnetic H-field is produced by fictitious magnetic charges that are spread over the surface of each pole. These magnetic charges are in fact related to the magnetization field M. The H-field, therefore, is analogous to the electric field E, which starts at a positive electric charge and ends at a negative electric charge.