Process Flow Of Neodymium Magnet

1. Raw material preparation and pretreatment:

Process Description: the raw materials are pre-treated by weighing, crushing, breaking and derusting.

Process equipment: steel cutting machine, drum polishing machine, etc

2. Smelting:

Process Description: the raw materials such as praseodymium neodymium, pure iron and ferroboron after pretreatment are proportioned, added into the vacuum smelting furnace, and the belt is thrown after high temperature smelting under the protection of argon. The results show that the product has uniform composition, high crystal orientation, good microstructure consistency and avoid the formation of λ - Fe.

Process equipment: vacuum melting furnace

3. Hydrogen explosion:

Process Description: hydrogen explosion (hd) process is to use the hydrogen absorption characteristics of rare earth intermetallics to place the neodymium iron boron alloy in the hydrogen environment. Hydrogen enters the alloy along the neodymium rich phase layer, making it expand, burst and break, and crack along the neodymium rich phase layer, so as to ensure the integrity of the main phase grains and the neodymium rich phase interphase. HD technology makes the Nd-Fe-B casting very loose, which greatly improves the efficiency of air flow mill and reduces the production cost.

Process equipment: Vacuum hydrogen treatment furnace

4. Pulverizing:

Process Description: air flow grinding is to use the high-speed collision of the material itself to crush, no wear and no pollution on the inner wall of the grinding chamber, so the powder can be prepared efficiently.

Process equipment: air mill

5. Forming orientation:

Process Description: the function of orientation is to turn the easy magnetization direction c axis of disorderly oriented powder particles to the same direction, so as to obtain the maximum remanence. The main purpose of pressing is to crush the powder into a certain shape and size, while maintaining the grain orientation obtained in the magnetic field orientation as much as possible. We design and use the forming magnetic field press and isostatic press for the secondary forming. For the special-shaped magnet, we use special mold tooling to directly form. After sintering, the magnet can be put into use only with a little surface treatment, which greatly saves the cost of materials and subsequent processing.

Process equipment: magnetic field press, isostatic press

6. Sintering:

Process Description: sintering is a simple and cheap way to change the microstructure of materials and improve the magnetic properties of materials. Sintering is the final forming process of materials, which has a very important influence on the density and microstructure of magnets.

Process equipment: vacuum sintering furnace

7. Machining:

Process Description: the Nd-Fe-B magnets obtained after sintering are all blanks, which need further machining to obtain products of different sizes, sizes and shapes. Because of its brittleness and poor mechanical properties, NdFeB magnets can only be grinded and machined.

Process equipment: surface grinder, double face grinder, chamfering machine

8. Surface treatment:

Process introduction: the surface treatment of various shapes of rare earth permanent magnets, such as electrophoresis, galvanizing, nickel, nickel copper nickel and phosphating, is carried out to ensure the appearance and corrosion resistance of the products.

9. Inspection and packaging of finished products:

Process Description: to test all kinds of magnetic properties, corrosion resistance, high temperature performance, etc. of the products, and pack them after reaching the standard, so as to meet the needs of customers.