The rare earth permanent magnetic material is an alloy composed of rare-earth metals and transition metals(such as cobalt, iron, etc.). It is pressed and sintered by powder metallurgical method and is made by magnetic field filling. Magnetic material. Permanent magnetic material refers to a material that can retain magnetism for a long time after being magnetized and removing the external magnetic field. Rare earth permanent magnetic material, namely rare earth permanent magnetic alloy. The permanent magnetic material contains rare earth metals as an alloy element.
Development history of rare earth permanent magnetic materials
From the perspective of development, rare earth permanent magnetic materials have roughly gone through three stages:

Classification of rare earth permanent magnetic materials
Since its inception in 1983, neodymium ferroboron permanent magnetic materials have been the most magnetic permanent magnetic materials in the world. Due to different preparation methods(or different uses), neodymium ferroboron permanent magnetic materials are mainly divided into two categories: sintering and bonding.
1. The sintered neodymium iron boron permanent magnet material sintering neodymium iron boron permanent magnet is formed and sintered after grinding the powder by the air flow, and its maximum magnetic energy product(BH) Max is more than 10 times higher than the ferrite. Sintered neodymium iron boron is very hard and brittle, but it can be cut into different shapes and drilled

Preparation process
At present, sintered neodymium iron boron permanent magnetic materials are mainly produced by sintering method(powder metallurgical method) in China. The main process is as follows: 2. The bonding germanium iron boron permanent magnetic material bonding germanium iron boron is a composite type of germanium iron boron permanent magnet made by evenly mixing germanium iron boron powder with resins, plastics or low melting point metals and other binders, and then made by compression, extrusion or injection molding. The product is formed at one time without secondary processing and can be directly made into a variety of complex shapes(above).

Preparation schedule:

The preparation process of bonding permanent magnets is more and more important than that of pressing and extruding molding in the production of bonding Nd-Fi-B magnets. Their process flow is shown in the figure below. The bonding process process is simple and the forming is accurate. No post-processing is required. The use of rare earth permanent magnetic materials is very extensive. With the Advancement of science and technology, rare earth permanent magnetic materials are not only used in computers, automobiles, instrumentation, household appliances, petrochemicals, medical care, aerospace and other industries. And in components such as nuclear magnetic resonance equipment, electrical devices, magnetic separation equipment, magnetic machinery, and magnetic therapy devices that need to generate strong magnetic fields, In addition, the demand for high-end rare earth permanent magnetic materials in emerging fields such as wind power generation, new energy vehicles, inverter appliances, energy-saving elevators, and energy-saving oil pumping machines is increasing, and the application market has huge space. As a strategic material, rare earth permanent magnet has been used in emerging industries, and it is an important basic material that has significantly improved the performance and efficiency of related products. At present, it has become the largest consumption area of rare earth new materials. In the future, we should continue to strengthen the exploration of new types of rare earth permanent magnetic materials, and strengthen the development of high-end rare earth permanent magnetic materials and related production technologies and equipment, so that China's rare earth permanent magnetic materials industry will maintain long-term and sustained development.