Permanent magnet ferrite is to SRO and Bao and Fe2O3 as raw material, made by ceramic technology (calcining, crushing, milling, pressing forming, sintering and grinding) manufacturing and has wide hysteresis loop, high coercivity and high remanence, the magnetization that is able to maintain a constant magnetic functional materials. According to different production technology, the permanent magnet ferrite is divided into two kinds of sintering and bonding. The sintering is divided into dry pressing and wet compression molding. Soft, elastic, and twisted magnets made of bonded ferrite powder and synthetic rubber are also known as rubber magnets. According to whether the external magnetic field is divided into isotropic permanent magnet and anisotropic permanent magnet.
At present, permanent ferrite prepared in various ways, but there are several methods are as follows:
(1) chemical co precipitation method,
(2) molten salt method,
(3) glass crystallization method,
(4) hydrothermal synthesis method,
(5) sol gel method,
(6) spray pyrolysis method,
(7) with organic resin method,
(8) self propagating high-temperature synthesis method.
New technology and new technology of permanent magnet ferrite
The way to improve the performance of the permanent magnet ferrite
(1) to improve the orientation degree.
(2) increasing sintering density.
(3) improving the Kl Mn of the ferrite M phase.
(4) to refine the grain size and improve the existence rate
(5) of single domain particles.