Introduction of wet pressing and dry pressing process of ferrite permanent magnet
Speaking of ferrite magnets, it is necessary to talk about its dry pressure and wet pressure. As for the difference between them, some introductions have been introduced in the previous article "Some Introduction to Dry Pressure and Wet Pressure Ferrite Magnets", such as the difference in magnetic properties. , Molding speed, etc. Today we will talk about the wet pressing and dry pressing of ferrite.
In the ferrite magnetic field molding process, the wet press molding process is to directly place the slurry after the secondary ball milling in the mold, and apply a certain direction (consistent with the direction of the magnetic field required when the product is used) during press molding. With a strong magnetic field, the easy magnetization axis of the single domain crystal grains are aligned along the direction of the external magnetic field. At the same time, the water must be pumped out when pressing, and the upper and lower punches need gaskets to prevent the slurry from being drawn out, and then dry after molding. Because of the high water content in the slurry, the wet-pressing molding process allows the crystal grains to rotate freely during the molding process, which facilitates the orientation of the crystal grains, and thus has good magnetic properties, high Br and high Hcb. However, gaskets and suction filtration are required during molding, which results in low production efficiency.
The figure below shows the performance parameters of wet-pressed anisotropic ferrite powder
Dry press molding is to add a proper amount of binder (Binder) to the dry powder without moisture after secondary ball milling, and place it in a molding magnetic field for compression molding. The magnetic field orientation of dry pressing is slightly worse, and the magnetic properties are worse than that of wet pressing.
The above is about the introduction of the two different processes of ferrite wet pressing and dry pressing. If you have purchase needs, remember to contact Courage.