Commonly used magnet classification and process differences

Magnets are commonly divided into the following categories: NdFeB magnets, SmCo magnets, AlNiCo magnets, and ferrite magnets.

So what are the costs and characteristics of these types of magnets?

Ferrite: low and medium performance, lowest price, good temperature characteristics, corrosion resistance, good cost performance

NdFeB: Highest performance, medium price, good strength, not resistant to high temperature and corrosion

Samarium cobalt: high performance, highest price, brittle, excellent temperature characteristics, corrosion resistance

AlNiCo: low and medium performance, medium price, excellent temperature characteristics, corrosion resistance, poor interference resistance

Samarium cobalt, ferrite, and NdFeB can be manufactured by sintering and bonding methods. The sintered magnetic properties are high, but the molding is poor. Bonded magnets have good moldability and much reduced performance. AlNiCo can be manufactured by casting and sintering methods. Cast magnets have high performance and poor formability, while sintered magnets have low performance and good formability.

The process characteristics of these types of magnets are listed below:

1. Ferrite magnet

Features: Its main raw materials include BaFe12O19 and SrFe12O19. Manufactured by the ceramic process method, the texture is relatively hard and it is a brittle material. Because of its good temperature resistance, low price and moderate performance, ferrite magnets have become the most widely used permanent magnets.

Features: It has higher magnetic properties, better time stability and lower temperature coefficient.

Ferrite magnet application places: widely used in electric meters, instruments, motors, automatic control, microwave devices, radar and medical equipment, etc.

Magnetizing direction of ferrite magnet: can be magnetized axially, radially or as required. Ferrite magnet shape: cylindrical, circular, rectangular, flat, tile, and axe shapes can be produced. 

2. AlNiCo magnet

AlNiCo magnet features: 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 with good machinability. Cast AlNiCo permanent magnets have the lowest reversible temperature coefficient, and the working temperature can be as high as 600℃. AlNiCo permanent magnet products are widely used in various instrumentation and other application fields.

Classification of AlNiCo magnets: It can be divided into two categories: cast AlNiCo and sintered AlNiCo.

Applications of AlNiCo: Cast AlNiCo products are mainly used in automotive parts, instrumentation, electroacoustics, motors, teaching, aerospace and military fields, with low temperature coefficient, high temperature resistance, moisture resistance, not easy to oxidize and work stability. Good and other advantages. Sintered AlNiCo is produced by powder metallurgy. It is suitable for the production of complex, light, thin and small products, and is widely used in instrumentation, communication, magnetoelectric switches and various sensors.

AlNiCo magnet shape: cylindrical, circular, rectangular, flat, tile, and horseshoe shapes can be produced.

3. 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 magnetic material made of samarium, cobalt and other metal rare earth materials through proportioning, melting into alloys, crushing, pressing and sintering. It has a high magnetic energy product and a very low temperature coefficient. The maximum working temperature can reach 350 ℃, and the negative temperature is not limited. When the working temperature is above 180 ℃, its maximum magnetic energy product, temperature stability and chemical stability are all higher than NdFeB permanent magnet materials. It has strong corrosion resistance and oxidation resistance; so it is widely used in aerospace, defense industry, microwave devices, communications, medical equipment, instruments, meters, various magnetic transmission devices, sensors, magnetic processors, motors, magnetic cranes Wait.

Samarium cobalt magnet production process: batching → smelting and ingot making → pulverizing → pressing → sintering and tempering → magnetic testing → grinding → cutting processing → finished product.

Samarium cobalt magnet shape: disc, ring, square, square, tile, special shapes can be processed according to requirements.