Immediately it should be noted that the magnets are divided into several classes.There are permanent magnets - it is usually certain pieces of metal and alloy, has a certain magnetism without external influence.And there is also the electromagnets.This technical devices in which a magnetic field is created by conducting an electric current through a special coil.
of the permanent magnets the category can be attributed only powerful neodymium.With a relatively small size, they have a tremendous magnetic characteristics.Firstly, its magnetic properties are lost only 1% for a hundred years.Second, when a relatively small size, they a
re of great magnetic force.Neodymium magnets are produced artificially.To create them requires the rare earth metal neodymium.Also used iron and boron.The resulting alloy is magnetized in a magnetic field.As a result, a neodymium magnet is ready.
The industry is widely used powerful electromagnets.Their design is much more complicated than that of the permanent magnets .To create the necessary powerful electromagnet coil consisting of a coil of copper wire and the iron core.The strength of the magnet in this case depends only on the current conducted through the coils, and the number of turns of wire on the coil.It is worth noting that at a certain current strength of magnetization of the iron core is saturated.Therefore, the most powerful industrial magnets are produced without it.Instead, it adds a number of more turns of wire.In most powerful industrial magnets with an iron core number of turns of wire is rarely more than ten thousand per meter, and used current - two amps.