Magnet Manufacturing Process
Making magnets takes several processes. However, the most common process for magnet production is known as Powder Metallurgy. This process involves pulverizing the raw materials into fine powder then compacted and heated through liquid phase sintering to achieve densification. Due to that, most of the magnets that are produced through this process is called sintered magnets. Manufacturing magnets usually takes up to 4 to 6 weeks. All the steps in manufacturing the magnets assures the customers with the best quality. Each magnet is composed of different materials. Hence, manufacturing processes are also different from each other.
The first step to manufacturing magnets is mining the raw materials.
It is a rapid processing technique where the materials is molten and poured i a shell mold.
HHDR process involves producing the bonded magnets that came from NdFeB sintered magnets with compositions.
After the liquid materials that are poured and cooled down, it is milled to broke down into tiny particles.
The super fine particles are pressed in a mold while applying the magnetic energy simultaneously using a coil wire.
After pressing the powder, a furnace is used for sintering process at over 1200⁰C in a hydrogen atmosphere. It fuses the pressed particles to create a one magnet.
This process measures the magnets’ magnetic field strength, pulling force, and other factors that contributes to a magnet’s strength.
In this process, all the raw magnets that are created are machined to achieve the desired shapes and sizes. Diamond plating cutting tool is required in this process.
Before the remagnetizing process, magnets will undergo into machining to be coated, cleaned, plated, and dried. Therefore, enhancing its resistance against chipping.
After adding a coating or plating, the magnets are remagnetized by placing it in a coil where the electric current will pass through. It then produces a magnetic field.
The final step in the magnet production process is packaging so it can be shipped in a perfect condition and safely to the customers.
Finishing
Sintered magnets undergoes machining processes such as grinding to achieve a smooth and parallel, block magnets, and more. The magnet materials are very hard yet brittle. Therefore, slicing the magnets requires diamond wheels. Slicing process allows to achieve excellent precision while eliminating subsequent grinding requirements. Aside from that, cylindrical magnets can also be pressed-to-shape. This process is usually economical.
To reduce the sharpness, the most common method used is vibratory tumbling. Neodymium magnets are always coated to reduce rusting. The most common coatings that are used are aluminum IVD, e-coat, zinc, iron, dry-sprayed epoxy, and more.
Magnetizing
After the magnet production process is completed, it undergoes charging to create an external magnetic field. It is achieved by using solenoid that is a characterized by its hollow cylinder. Therefore, desired shapes and sizes are met. Other fixtures or unique magnet patterns can also be placed in a solenoid to produce magnetic field.
Large magnetic assemblies can also be magnetized using a solenoid to assembling and handling powerful magnets. The magnetizing field process is very substantial. If you need to know more about this process, Dailymag production and engineering team is ready to help you.
