The injection molded magnets are composed of nylon and magnetic powder, which is produced by injection molding with a special injection molding machine. Compared with other manufacturing methods of permanent magnets, injection molded magnets have unique and irreplaceable advantages.
Injection moulding can produce magnets of complex shapes. In addition, the injection molding process can adopt "embedded molding", "multi-step molding", and "multi-workpiece molding" to combine the magnet with other parts into a whole for forming, thus saving the cost of secondary processing and assembly. Injection molding technology can produce both isotropic and anisotropic magnets. When the anisotropic magnet is formed, it needs to be applied with oriented magnetic field, so that the magnetic powder has a certain orientation in the polymer in the molten state, that is, orientation occurs, and multi-pole magnetization can be realized. The injection molding process makes the products have good consistency in size and performance.
In the molding process, the mold cavity is completely filled with the material at the highest concentration under the strong injection pressure, and the material contains thermoplastic binder, so that the magnet has good physical and mechanical properties. Due to the high content of polymer binder in the injection molded magnet, the magnet itself has a strong anti-corrosion ability, and usually does not need surface coating protection.
Dimensional accuracy: since the size of the injection molded product is consistent with the injection mold cavity, the dimensional accuracy of the product can be controlled relatively high. In addition, the shrinkage of the binder in the material during cooling will also cause the change of product size. The degree of shrinkage depends on the thickness and shape of the product. Typical dimensional tolerances are: ±0.05mm.