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Neodymium iron boron magnets, as the latest result of the development of rare earth permanent magnetic materials, are called "magnet kings" due to their excellent magnetic properties.

Neodymium iron boron magnets are alloys of neodymium and iron oxide. Also known as magnet.

NdFeB material contains a lot of neodymium and iron, which is easy to rust. Therefore, neodymium iron boron magnets must be surface coated. Surface chemical passivation is currently one of the good solutions. NdFeB has extremely high magnetic energy product and coercive force, and 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. The advantages of NdFeB are high cost performance and good mechanical properties; the shortcomings are that the Curie temperature is low, the temperature characteristics are poor, and it is easy to pulverize and corrode. It must be improved by adjusting its chemical composition and adopting surface treatment methods. In order to meet the requirements of practical applications.

classification:

NdFeB is divided into two types: sintered NdFeB and bonded NdFeB. Bonded NdFeB has magnetism in all directions and is corrosion-resistant; while sintered NdFeB is easy to corrode, and the surface needs to be coated, generally galvanized, Nickel, environmental protection zinc, environmental protection nickel, nickel copper nickel, environmental protection nickel copper nickel, etc. Sintered NdFeB is generally divided into axial magnetization and radial magnetization, depending on the required working surface.

chemical composition:

The NdFeB permanent magnet material is a permanent magnet material based on the intermetallic compound RE2FE14B. The main components are rare earth (RE), iron (FE), and boron (B). In order to obtain different properties, rare earth ND can be replaced by some other rare earth metals such as dysprosium (Dy) and praseodymium (Pr). Iron can also be partially replaced by other metals such as cobalt (Co) and aluminum (Al). The content of boron is small, but However, it plays an important role in the formation of tetragonal crystal structure intermetallic compounds. The compound has high saturation magnetization, high uniaxial anisotropy and high Curie temperature.

Grade:

Each type of product is divided into several grades according to the maximum magnetic energy product. The grades of NdFeB magnetic materials are: N35—N52, N35M—N50M, N30H—N48H, N30SH—N45SH, N28UH—N35UH, N28EH—N35EH.

Digital grade

Brand example: 048021 means (BH) max is 366~398kj/m3, Hcj is 800KA/m sintered NdFeB permanent magnet material.

Character brand

The grades of sintered NdFeB permanent magnet materials are composed of three parts, the main name and two magnetic properties. The first part is the main name, consisting of the chemical symbol ND of neodymium element, the chemical symbol of iron element FE and the chemical symbol of boron element B. The second part is the number before the line, which is the nominal value of the material’s maximum magnetic energy product (BH) max (unit: kj/m3), and the third part is the number after the diagonal line, the coercive force value of the magnetic polarization (unit is KA /m), the value is rounded up.

Brand example: NdFeb380/80 means (BH) max is 366~398kj/m3, Hcj is 800KA/MR sintered neodymium iron boron permanent magnet material.

application:

Sintered NdFeB permanent magnet materials have excellent magnetic properties and are widely used in electronics, electrical machinery, medical equipment, toys, packaging, hardware machinery, aerospace and other fields. The more common ones are permanent magnet motors, speakers, magnetic separators, Computer disk drives, magnetic resonance imaging equipment meters, etc.

Medical function:

NdFeB permanent magnets are high-tech materials for the National 863 Project. What he can generate is a biomagnetic field that simulates the characteristics of the human body's magnetic field, with stable performance! Acting on the human body, it can correct the human body’s own magnetic field, and by enhancing the bio-electromagnetic energy of the human body’s meridians, promote the movement of the meridians, so as to achieve the passage of the meridians, increase the brain’s blood supply and oxygen, reduce the excitability of the peripheral nerves of the cerebral cortex, and promote bone The effect of joint tissue metabolism, hypnosis, analgesia, sedation, blood circulation and anxiety elimination. Currently commonly used to treat insomnia, neurasthenia, cervical spondylosis, frozen shoulder, lumbar muscle strain, lumbar disc herniation and other chronic bone and joint diseases, as well as the pain and numbness caused by these diseases