You will need
- a piece of low carbon electrical steels, cylindrical shape, insulated copper wire, a constant current source.
Take a blank of electrical steel and carefully, turn to turn her wrap insulated copper wire. Wire take the middle cross-section in order to fit more turns, but at the same time not too thin, so he doesn't burn out from high current.
After that, connect the wire to the DC power source through the rheostat, if in the source there is no possibility to adjust the voltage. For such a magnet is enough of a source that emits up to 24 V. After that, move the slider of the rheostat at maximum resistance, or the controller of the source at the minimum voltage.
Slowly and carefully increase the voltage. This displays the characteristic vibration accompanied by sound, which you can hear in the transformer is normal. Be sure to monitor the winding temperature, since it depends on the duration of the electromagnet. Bring the voltage up to that value at which the copper wire will begin to heat up clearly. After that, cut the power and allow the winding to cool. Again turn on the current and through such manipulation to find the maximum voltage at which the conductor is not heated. This will be the nominal mode of operation is made , the electromagnet.
Move to one of the poles of the operating magnet body from the substance, which contains iron. It should firmly be attracted to the magnet nickle (nickle believe the base is a steel core). If the force of attraction is insufficient, take the cable with greater length and put the coils in several layers, proportionally increasing magnetic field. The conductor resistance will increase, and his adjustment would be needed again.
Magnet better attracted, take the core is u-shaped and wrap wire it straight - then the surface gravity and its strength will increase. To increase the force of gravity, make a core of an alloy of iron and cobalt, the conductivity of the magnetic field which is slightly higher.
Advice 2: How to make a powerful magnet
The creation of a powerful electromagnets is a difficult technical task. In industry, as indeed in everyday life magnets of great power is required. In some States, even working trains on a magnetic cushion. The machine is with electromagnetic motor soon massively and we will be under the brand name "E-mobility". But how are the magnets of great power?
It is worth noting that the magnets are divided into several classes. There are permanent magnets is, as a rule, pieces of a specific metal alloy, possessing a certain magnetism without outside influence. But there are also electromagnets. This technical devices in which a magnetic field is generated by conducting electric current through a special coil.
Of the permanent magnets to the category of powerful can be attributed only to neodymium. With a relatively small size, they are simply stunning magnetic characteristics. First, their magnetic properties, they lose only 1% for a hundred years. Second, despite its relatively small size, they have a huge magnetic force. Neodymium magnets are made artificially. To create the necessary rare earth metal neodymium. Also used iron and boron. The resulting alloy is magnetized in a magnetic field. In the end, the neodymium magnet is ready.
In industry, widely used in powerful electromagnets. Their design is much more complicated than that of permanent magnets. To create a strong electromagnet required coil consisting of windings of copper wire and iron core. Magnetic force in this case depends on the current drawn through the coil and number of turns of wire in the winding. It is worth noting that at a certain current strength the magnetization of the iron core undergoes saturation. Therefore, the most powerful industrial magnets are manufactured without him. Instead, you add an additional number of turns of wire. The most powerful industrial magnets with iron core the number of turns of wires rarely exceeds ten thousand per meter, and used the current is two amperes.