What are the characteristics and processing technology of ferrite magnets?
Features: Its main raw materials include BaFe12O19 and SrFe12O19. Manufactured by ceramic technology, the texture is relatively hard and is a brittle material. Because ferrite magnets have good temperature resistance, low price, and moderate performance, they have become the most widely used permanent magnets. Features: High magnetic properties, good time stability and low temperature coefficient. Applications of ferrite magnets: Widely used in electric meters, instruments, motors, automatic control, microwave devices, radar and medical equipment, etc. Ferrite magnet magnetization direction: can be magnetized axially, radially or as required. Ferrite magnet shape: can produce cylindrical, circular, cuboid, flat, tile, axe.
Characteristics and processing technology of AlNiCo magnets
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, and the machinability is good. 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 magnets and sintered AlNiCo magnets.
Alnico application places: cast Alnico products are mainly used in the fields of auto parts, instruments, electroacoustics, motors, teaching, aerospace and military, etc., 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 and is suitable for the production of complex, light, thin and small products. It is widely used in instruments and meters, communications, magnetoelectric switches and various sensors.
Alnico magnet shape: can produce cylindrical, circular, cuboid, flat, tile, horseshoe.
Characteristics and processing technology of SmCo magnets?
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 high magnetic energy products and extremely low temperature coefficient. The maximum working temperature can reach 350°C, and the negative temperature is not limited. When the working temperature is above 180°C, its maximum magnetic energy product, temperature stability and chemical stability are all higher than that of NdFeB permanent magnet materials. It has strong corrosion resistance and oxidation resistance; so, it is widely used in aerospace, national defense, 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: batching → smelting ingots → powder making → pressing → sintering and tempering → magnetic testing → grinding → cutting processing → finished products.
SmCo magnet shape: disk, ring, square piece, square bar, tile shape, special shape can be processed according to requirements.
Magnetic field orientation and pressing
Powder magnetic field orientation is one of the key technologies for manufacturing high-performance sintered magnets. The purpose of magnetic field orientation is to make the easy magnetization direction (c-axis) of each powder particle be oriented in the same direction to make an anisotropic magnet, and then the direction along the c-axis orientation of the powder particle has the largest remanence Br, thereby improving the magnetism. The maximum magnetic energy product. The orientation of the powder has an important influence on the remanence Br and the maximum energy product (BH) max of the magnet. Powder compaction has two purposes: one is to press the powder into a compact of a certain shape and size according to user needs; the other is to maintain the degree of crystal orientation obtained in the magnetic field orientation. There are three commonly used pressing methods: mold pressing, mold pressing and cold isostatic pressing, and rubber molding (and cold isostatic pressing).
The pressing process is the main process for the magnetic powder to absorb oxygen, so strict anti-oxidation measures are taken during the forming process, and the weighing or pressing process of the magnetic powder is required to be operated under the protection of an inert gas. The equipment used in this process is a forming press.
Orientation direction of the magnet?
Sintered NdFeB permanent magnets are anisotropic magnets. Orientation direction: The direction in which an anisotropic magnet can obtain the best magnetic properties is called the orientation direction of the magnet, also known as "orientation axis" or "easy magnetization axis".
How do you judge the magnetization direction of the magnet?
Pole test strips are available. The principle of the magnetic pole test piece is actually to put some iron powder in the compartment, and then clamp it with transparent things. When there is a magnetic force, the magnetic powder in the interlayer will attract it, and there will be no magnetic powder in the non-magnetic area, so that the distribution of the magnetic poles can be observed.
What kind of magnet can be used in water?
Depending on the material, not every magnet can be used in water. A corroded and rusted magnet can be a hazard to aquatic life. Ferrite has strong corrosion resistance and oxidation resistance, and can be used normally in water.
What is a magnetic tile?
Magnetic tiles are a kind of tile-shaped magnet mainly used in permanent magnet motors in permanent magnets.
What are the production processes of ferrite tiles?
Ferrite tiles are mainly sintered ferrite. The production process of sintered ferrite magnetic tiles is mainly divided into wet pressing with different sex, dry pressing with same sex, and dry pressing with different sex. Here mainly introduces the process of wet pressing anisotropy. The wet pressing process is: raw material→pre-calcination→coarse crushing (primary ball milling) →batching→secondary ball milling (wet milling) →magnetic field forming→sintering→grinding→cleaning→magnetizing. Because the molding slurry contains moisture, the molding particles are easy to turn in the magnetic field, so it can obtain a higher degree of orientation than dry pressing, and its performance is also higher.
NdFeB magnetic tile production process
Sintered NdFeB magnetic tile: batching → smelting → crushing → powder making → magnetic field forming → isostatic pressing → vacuum sintering and tempering → wire cutting and other processing → electroplating → magnetization.