Magnets include NdFeB magnet, permanent magnet ferrite magnet, samarium cobalt magnet, Al-Ni-Co magnet and Fe-Cr-Co magnet. Among them, the ferrite magnet can't conduct electricity, and the other four magnets can conduct electricity, but the conductivity depends on the composition of the magnet itself every time.
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Magnets are made up of atoms such as iron, cobalt and nickel. Their atoms have special internal structures and have their own magnetic moments. Magnets can generate magnetic fields and attract ferromagnetic substances, such as iron, nickel, cobalt and other metals.
first kind
Sintered Rb-Fe-B: It is a new type of permanent magnet material developed after 1983. With extremely high magnetic properties, it is widely used in various permanent magnet motors, construction machinery, electroacoustic, electrical appliances and medical devices.
Sintered samarium cobalt permanent magnet is an excellent permanent magnet material, which has high magnetic measurement performance, strong corrosion resistance, oxidation resistance, low temperature coefficient and high Curie temperature. It can be used in high environment and widely used in high-tech fields such as motors, sensors, detectors and radars.
Al-Ni-Co is suitable for producing complex shapes. The products are light, thin and small, and are widely used in instruments, communications, magnetoelectric switches and various sensors.
second kind
1, neodymium magnet: it is the magnet with the highest commercial performance found at present, and is called the magnetic king. Its machinability is also quite good. The working temperature can reach up to 200 degrees Celsius. But also because of its hard texture, stable performance, good cost performance and wide application. However, due to its strong chemical activity, its surface must be treated. (such as zinc plating, nickel plating, electrophoresis, passivation, etc. ).
2. Ferrite magnet: Its main raw materials include BaFe 12O 19 and SrFe 12O 19. Made of ceramic technology, it is a brittle material with hard texture. Ferrite magnet has become the most widely used permanent magnet because of its good temperature resistance, low price and moderate performance.
3. Al-Ni-Co magnet: It is an alloy composed of trace metal elements such as aluminum, nickel, cobalt and iron. The casting process can be processed into different sizes and shapes, and the machinability is very good. The reversible temperature coefficient of the cast Al-Ni-Co permanent magnet is the lowest, and the working temperature can be as high as 600 degrees Celsius. Al-Ni-Co permanent magnet products are widely used in various instruments and other application fields.
4.SmCo: It can be divided into SmCo5 and Sm2Co 17 according to different components. Its development is limited by the high price of its materials. As a rare earth permanent magnet, SmCo not only has high magnetic energy product (14-28MGOe), reliable coercivity and good temperature characteristics. Compared with neodymium magnet, samarium cobalt magnet is more suitable for working in high temperature environment.