Magnet Manufacturing Process

A high frequency is applied to the raw materials in the vacuum melting furnace, causing them to melt. As the temperature rises, the alloy becomes homogeneous and is then poured into molds to form ingots.

3. Pulverization

After several passes, the ingots are pulverized into very fine particles, averaging just a few microns in diameter. This pulverization process occurs in a protected environment of argon or nitrogen to prevent oxidation of the particles.

4. Stamping in magnetic field

Magnetic powder, subjected to an applied magnetic field, is pressed into a mold. This process ensures that the particle crystals align with the direction of the external magnetic field, enhancing the orientation and effectiveness of the magnetic properties.

5. Sintering and heat treatment

The pressed compound undergoes sintering and heat treatment in the vacuum melting furnace. This process "cooks" the compound until it achieves a density close to its true density. At this stage, the dimensions of the sintered compound are compacted by 70-80% compared to the pressed form, with the volume reduced to approximately half. The heat treatment post-sintering regularizes the metallic structure of the magnetic alloy, enhancing its properties.

6. Inspection of magnetic characteristics

After the sintering and heat treatment process is completed, the basic magnetic characteristics of the magnet are established. Key properties such as residual magnetic flux density, coercivity, and maximum energy product are measured. Only magnets that meet the required standards are approved for the subsequent processing and assembly steps.

7. Processing

During sintering, rare earth magnets experience significant shrinkage. To remove the oxidation layer formed on the surface, the magnets undergo a polishing or cutting treatment to achieve the desired dimensions.

8. Surface treatment

The magnets undergo surface treatment tailored to the environment in which they will be used. Neodymium magnets, which are prone to rusting, typically receive a nickel plating or coating for protection. In contrast, samarium-cobalt magnets, known for their excellent anti-corrosion properties, generally do not require any surface treatment.

9. Visual inspection of appearance

Following machining and surface treatment, thorough visual inspections are conducted to assess appearance and dimensions. Additionally, rigorous testing is performed to verify the magnetic and anti-corrosion characteristics, in accordance with the technical specifications of the product.