NdFeB process

- Dec 13, 2018 -

1. Raw material preparation and pretreatment

Process Description: Pretreatment of raw materials, weighing, breaking, and rust removal.


2. Melting

Process introduction: The pretreated raw materials 镨钕, pure iron, boron iron, etc. are proportioned and added to the vacuum melting furnace. After high temperature smelting under the protection of argon gas, the bismuth zone is carried out to make the product components uniform and the crystal orientation degree is high. Good organization and avoid the formation of bismuth-iron.


3. Hydrogen explosion

Process Description: The hydrogen explosion (HD) process utilizes the hydrogen absorption characteristics of rare earth intermetallic compounds. The neodymium iron boron alloy is placed in a hydrogen atmosphere, and the hydrogen enters the alloy along the thin layer of the rich phase, causing it to expand and burst and break. Cracking at the rich phase layer ensures the integrity of the main phase grain and the intergranular boundary. The HD process makes the tantalum sheet of NdFeB very loose, greatly improving the milling efficiency of the jet mill and reducing Production costs.


4. Milling

Process Introduction: Airflow milling powder is pulverized by high-speed collision of the material itself. It has no wear and no pollution to the inner wall of the grinding chamber, and can prepare powder with high efficiency.


5. Molding orientation

Process introduction: The role of orientation is to make the axis of easy magnetization of chaotically oriented powder particles turn in the same direction, so that the main purpose of obtaining the largest residual magnetic pressure type is to press the powder into a certain shape and size. Bad, while maintaining the degree of grain orientation obtained in the orientation of the magnetic field as much as possible. We design a shape magnetic field press and an isostatic press for secondary molding. For special-shaped magnets, special mold tooling is used for direct molding. The sintered magnets can be put into use only with a slight surface treatment, which greatly saves materials. And subsequent processing costs.


6. Sintering

Process Introduction: Sintering is a series of physicochemical changes that occur at high temperatures. It is a simple and inexpensive way to change the microstructure of materials to improve the magnetic properties of materials. Sintering is the final forming process of materials, the density of magnets. And the microstructure has a very important impact.


7. Machining

Process Description: NdFeB magnets obtained after sintering are blanks, which need further machining to obtain various sizes, sizes and shapes. NdFeB magnets are relatively brittle and have poor mechanical properties. Generally, only grinding can be used. Machining and cutting.


8. Surface treatment

Process Description: Surface treatment of various shapes of rare earth permanent magnets, such as electrophoresis, galvanizing, nickel, nickel-copper-nickel and phosphating, to ensure the appearance and corrosion resistance of the product.


9. Finished product inspection and packaging

Process Description: The product's various magnetic properties, corrosion resistance, high temperature performance, etc. are tested and packaged to meet the various needs of customers.


  • Solenoid Electromagnet
  • Injection Plastic Magnet
  • AlNiCO Magnets
  • Sintered NdFeB Magnets
  • Wireless Amplifier
  • Mini Bluetooth Amplifier

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