The unique properties of certain substances have always surprised people with their unusualness. Particular attention was drawn to the ability of some metals and stones to repel or attract each other. Throughout all ages, this has aroused the interest of the sages and the great surprise of ordinary inhabitants.
From the 12th to 13th centuries it began to be actively used in the production of compasses and other innovative inventions. Today you can see the prevalence and variety of magnets in all areas of our lives. Each time we meet another magnet product, we often ask ourselves: “So how do magnets do?”
Types of Magnets
There are several types of magnets:
- Constant;
- Temporary;
- Electromagnet;
The difference between the first two magnets lies in their degree of magnetization and the retention time of the field inside themselves. Depending on the composition, the magnetic field will be weaker or stronger and more resistant to external fields. An electromagnet is not a real magnet, it is just the effect of electricity, which creates a magnetic field around a metal core.
Interesting fact: For the first time, research on this substance was carried out by our domestic scientist Peter Peregrin. In 1269, he published the “Book of the Magnet,” which described the unique properties of matter and its interaction with the outside world.
What are magnets made of?
To produce permanent and temporary magnets, iron, neodymium, boron, cobalt, samarium, alnico and ferrite are used. They are crushed in several stages and melted, baked or pressed together to obtain a permanent or temporary magnetic field. Depending on the type of magnets and the required characteristics, the composition and proportions of the components change.
This production allows you to get three types of magnets:
- Pressed;
- Cast;
- Sintered;
Magnet Making
Electromagnets are produced by wrapping a wire around a metal core. Changing the size of the core and the length of the wire change the field power, the amount of electricity used and the size of the device.
Component Selection
Permanent and temporary magnets are produced with different field strengths and resistance to environmental influences. Before starting production, the customer determines the composition and form of future products, depending on the place of application and the high cost of production. Up to a gram, all components are selected and sent to the first stage of production.
Smelting
The operator loads all the components of the future magnet into an electric vacuum furnace. After checking the equipment and the conformity of the amount of material, the furnace is closed. Using a pump, all air is pumped out of the chamber and the melting process is started. The air from the chamber is removed in order to prevent oxidation of iron and a possible loss of field power. The molten mixture is independently poured into the mold, and the operator expects it to cool completely.The result is a briquette that already has magnetic properties.
Shredding
Homogeneous alloy in special crushers is crushed in two stages. As a result of the primary crushing of the briquette, large particles are obtained, the size of a small gravel. After secondary crushing, a powder is formed with a particle size of several microns. This is necessary, in the next step, to correctly set the magnetic fields.
Pressing
The powder is loaded into a special apparatus, where under the influence of a magnetic field and mechanical pressure it is pressed into briquettes of the required size and shape. During exposure to a magnetic field, magnetized particles inside the powder are sent in one direction. As a result, the polarity of the future magnet is aligned. Ready briquettes are packed in sealed bags and pumped air from the inside. This is necessary to prevent oxidation of the metal and loss of magnetic properties.
Sintering
The briquette is placed in a special furnace from which air is removed and, under the influence of high temperature, all components are sintered into a single magnet. The product gains high strength and increases the power of magnetic fields.
Production completion
Magnets can be additionally cut, ground and coated with a protective layer. Finished products pass quality control, are packaged and sent to the customer.
Interesting fact: The first magnetic ore mine was built on the hills of magnesia in Asia Minor. Many tons of ore have been mined from its bowels,which was used for the production of compasses and other unique tools.
The production technology of magnets consists in mixing several components and obtaining a product that emits a magnetic field. Depending on the composition and proportions, in each case, the process will be slightly different. Finished products will be used in various areas of our lives, from large electric motors to souvenirs on the refrigerator.
