Know "Strontium iron boron"

NdFeB magnetic materials, as the latest result of the development of rare earth permanent magnetic materials, are called "magnetic kings" because of their excellent magnetic properties. NdFeB magnetic materials are alloys of niobium, iron oxide, and the like. Also known as magnetic steel. Neodymium iron boron has a very high magnetic energy product and corrective force, and at the same time, the advantage of high energy density makes NdFeB permanent magnet materials widely used in modern industry and electronic technology, so that instrumentation, electro-acoustic motor, magnetic separation magnetization Equipment such as miniaturization, light weight, and thinness are possible. The advantages of neodymium-iron-boron are its high performance-to-price ratio and good mechanical properties; its disadvantages are its low Curie temperature point, poor temperature characteristics, and its tendency to pulverize and corrode, which must be improved by adjusting its chemical composition and adopting surface treatment methods. In order to meet the requirements of practical applications.

classification

Neodymium iron boron is divided into two kinds of sintered neodymium-iron boron and bonded neodymium iron boron, bonded neodymium iron boron in all directions are magnetic, corrosion resistance; and sintered neodymium iron boron due to corrosion, the surface needs to be coated, generally galvanized, Nickel, environmental zinc, environmental protection nickel, nickel-copper-nickel, environmental protection nickel, copper and nickel. The sintered Nd-Fe-B is generally divided into axial magnetization and radial magnetization, according to the required working surface.

chemical composition

NdFeB permanent magnet materials are permanent magnetic materials based on the intermetallic compound RE2FE14B. The main components are rare earth (Re), iron (Fe), and boron (B). The rare earth ND can be replaced by other rare earth metals such as Dy and Pr for obtaining different properties. Iron can also be replaced by other metals such as cobalt and aluminum, and the content of boron is small, but However, it plays an important role in the formation of tetragonal crystal structure intermetallic compounds, resulting in compounds with high saturation magnetization, high uniaxial anisotropy and high Curie temperature.

The third generation of rare earth permanent magnet NdFeB is the most powerful permanent magnet in contemporary magnets, and its main raw materials are rare earth metals 钕29%-32.5% metal element iron 63.95-68.65% non-metallic element boron 1.1-1.2% small amount to add镝0.6-1.2% 铌0.3-0.5% aluminum 0.3-0.5% copper 0.05-0.15% and other elements.

Grade

Overview

Each type of product is divided into several brands according to the maximum energy product size

NdFeB magnetic material grades are: N35-N52, N35M-N50M, N30H-N48H, N30SH-N45SH, N28UH-N35UH, N28EH-N35EH.

Digital number

Grades Example: 048021 means sintered NdFeB permanent magnet material with (BH)max of 366~398kj/m3 and Hcj of 800KA/m.

Character number

The grades of sintered NdFeB permanent magnet materials are composed of three parts of the main composer's two magnetic properties. The first part is mainly called by the chemical symbol ND of the lanthanum element, the chemical symbol FE of the iron element and the chemical symbol B of the boron element. The second part is the number before the line, which is the nominal value (in kj/m3) of the maximum energy product (BH)max of the material. The third part is the number after the slash, and the coercive force value of magnetic polarization (in KA). One-tenth of /m) The value is rounded off.

Grades example: NdFeb380/80 is a sintered NdFeB permanent magnet material with (BH)max of 366~398kj/m3 and Hcj of 800KA/MR.

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 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 produce is a biological magnetic field that mimics the characteristics of the human body's magnetic field. The performance is stable! The human body can correct the magnetic field of the human body, and enhance the biological electromagnetic energy of the meridians of the human body to promote the operation of the gas to reach the meridians. Increase blood supply and oxygen supply to the brain, reduce excitability of the peripheral nerves of the cerebral cortex, increase the supply of oxygen and oxygen to the lungs, spleen, liver, and perianal organs, promote local blood circulation, and return the venous blood to reduce the capillary volume. The permeability of blood vessels promotes the absorption and dissipation of inflammation and results in the promotion of bone and joint tissue metabolism, hypnosis, anti-inflammatory analgesia, sedation, blood circulation, and anxiety elimination. Currently used to treat insomnia, neurasthenia, bronchitis, asthma, cervical spondylosis, frozen shoulder, acne, constipation, lumbar muscle strain, lumbar disc herniation and other system diseases, and these diseases caused by pain, numbness and other symptoms.

Edit this section Sintered NdFeB production process

Process flow: Ingredients → Smelting ingot/stripping → Milling → Pressing → Sintering → Magnetic detection → Grinding → Pin cutting → Plating → Finished product. Wherein the ingredients are the basis, sintering and tempering are the key.

NdFeB magnet production tools: smelting furnace, rejection belt furnace, crusher, jet mill, press molding machine, vacuum packaging machine, isostatic press, sintering furnace, heat treatment vacuum furnace, magnetic performance tester, Gauss meter.

NdFeB magnet processing tools: special slicing machine, wire cutting machine, flat grinding machine, double-sided machine, drilling machine, chamfering machine, electroplating equipment.