1. There are many types of magnets, which are generally divided into two categories: permanent magnets and soft magnets. Permanent magnets are divided into two categories:
The first category is: metal alloy magnets, including neodymium iron boron magnets, samarium cobalt magnets, and alnico magnets.
The second category is: ferrite permanent magnet materials
Ferrite Magnet
The main raw materials of ferrite include BaFe12O19 and SrFe12O19. Manufactured by ceramic technology, the texture is relatively hard and it is a brittle material. Due to the good temperature resistance, low price and moderate performance of ferrite magnets, it has become the most widely used permanent magnet.
Neodymium iron boron magnet
Neodymium iron boron is currently the most commercially available magnet. It is called the Magneto. It has extremely high magnetic properties and its maximum energy product (BHmax) is more than 10 times higher than that of ferrite. Its own mechanical processing performance is also quite good. The operating temperature can reach up to 200 degrees Celsius. Moreover, its texture is hard, its performance is stable, and its cost performance is very good, so its application is extremely wide. But because of its strong chemical activity, it must be treated with a surface coating. (Such as Zn, Ni, electrophoresis, passivation, etc.).
Samarium Cobalt Magnet
Samarium cobalt magnets (SmCo) are divided into SmCo5 and Sm2Co17 according to their composition. Due to the high price of samarium cobalt materials, its development is restricted. As a rare earth permanent magnet, Samarium Cobalt Magnet (SmCo) not only has a high magnetic energy product (14-28MGOe), reliable coercivity and good temperature characteristics. Compared with neodymium iron boron magnets, samarium cobalt magnets are more suitable for working in high temperature environments.
AlNiCo Magnet
AlNiCo is an alloy composed of aluminum, nickel, cobalt, iron and other trace metal elements. The casting process can be processed into different sizes and shapes, and the workability is very good. Cast AlNiCo permanent magnets have the lowest reversible temperature coefficient, and the operating temperature can be as high as 600 degrees Celsius. Alnico permanent magnet products are widely used in various instruments and other applications.
2. The magnetic force is arranged as follows: neodymium iron boron magnet, samarium cobalt magnet, alnico magnet, ferrite magnet.
Neodymium iron boron magnet
Features: NdFeB permanent magnet material is a permanent magnet material based on the intermetallic compound Nd2Fe14B. NdFeB has extremely high magnetic energy product and coercive force. At the same time, the advantages of high energy density make NdFeB permanent magnet materials widely used in modern industry and electronic technology, thereby making instrumentation, electroacoustic motors, and magnetic separation magnetization The miniaturization, weight reduction, and thinning of equipment are possible.
Material characteristics: NdFeB has the advantages of high cost performance and good mechanical properties; the disadvantage is that the Curie temperature is low, the temperature characteristics are poor, and it is easy to pulverize and corrode. It must be adjusted by its chemical composition and surface treatment methods. It can be improved to meet the requirements of practical applications.
Manufacturing process: NdFeB is manufactured using powder metallurgy technology.
Technological process: ingredients → smelting ingots → powder making → profiling → sintering and tempering → magnetic inspection → grinding processing → pin cutting processing → electroplating → finished product.
Ferrite Magnet
Ferrite magnet features: Its main raw materials include BaFe12O19 and SrFe12O19. Manufactured by ceramic technology, the texture is relatively hard and it is a brittle material. Due to the good temperature resistance, low price and moderate performance of ferrite magnets, it has become the most widely used permanent magnet.
Ferrite magnet characteristics: It has higher magnetic properties, better time stability and lower temperature coefficient.
Ferrite magnet applications: widely used in electricity meters, meters, motors, automatic controls, microwave devices, radars and medical equipment, etc.
Magnetizing direction of ferrite magnet: It can be magnetized axially, radially or as required.
Ferrite magnet shape: can produce cylindrical, circular, rectangular, flat, tile, axe-shaped.
AlNiCo Magnet
Features of AlNiCo magnet: It is an alloy composed of aluminum, nickel, cobalt, iron and other trace metal elements. The casting process can be processed into different sizes and shapes, and the workability is very good. Cast AlNiCo permanent magnets have the lowest reversible temperature coefficient, and the operating temperature can be as high as 600 degrees Celsius. Alnico permanent magnet products are widely used in various instruments and other applications.
Classification of AlNiCo magnets: It can be divided into two categories: cast AlNiCo and sintered AlNiCo magnets.
Al-Ni-Co applications: Cast Al-Ni-Co products are mainly used in automotive parts, instrumentation, electro-acoustics, electrical machinery, teaching, aerospace and military applications, with low temperature coefficient, high temperature resistance, moisture resistance, oxidation resistance and working stability Good to wait for the advantages. Sintered AlNiCo is produced by powder metallurgy. It is suitable for the production of complex, light, thin and small products. It is widely used in instrumentation, communications, magnetoelectric switches and various sensors.
Shapes of AlNiCo magnets: cylindrical, circular, rectangular, flat, tile, and horseshoe shapes can be produced.
Samarium Cobalt Magnet
Samarium cobalt magnets are also called samarium cobalt magnets, samarium cobalt permanent magnets, samarium cobalt permanent magnets, samarium cobalt strong magnets, rare earth cobalt permanent magnets, etc. It is a kind of magnetic material made of samarium, cobalt and other metal rare earth materials through proportioning, melting into alloy, crushing, pressing, and sintering. It has a high magnetic energy product, a very low temperature coefficient, and a maximum operating temperature. Up to 350℃, the negative temperature is not limited. When the working temperature is above 180℃, its maximum magnetic energy product, temperature stability and chemical stability exceed the neodymium iron boron permanent magnet material. It has strong corrosion resistance and oxidation resistance; so it is widely used in aerospace, defense and military industry, microwave devices, communications, medical equipment, instruments, meters, various magnetic transmission devices, sensors, magnetic processors, motors, magnetic cranes Wait.
The production process of samarium-cobalt magnets: ingredients → smelting ingots → powder making → pressing → sintering and tempering → magnetic inspection → grinding processing → pin cutting processing → finished product
Typical shapes of samarium cobalt magnets: circle, ring, square, square, tile, special shape can be processed according to the requirements.