1. Neodymium iron boron permanent magnet material is a kind of material with strong magnetism. All kinds of materials and materials around us have large or small magnetism, generally very weak. There are not many substances and materials with strong magnetism. Among the more than one hundred elements in the periodic table, only iron, cobalt, nickel and gadolinium have strong magnetism at room temperature. Some ferrites also have strong magnetism at room temperature.

　　The so-called magnetic substances, in layman's terms, is to use a magnet to attract it, it can be firmly attracted, feel the magnetism is very strong, so they are called strong magnetic substances, or strong magnetic materials. NdFeB is an intermetallic compound composed of three elements of neodymium, iron and boron, and is an excellent magnetic material. After being magnetized, the magnetism it exhibits is not only very strong, but also can be maintained for a long time, and it can be maintained almost permanently. It is an excellent permanent magnetic material.

　　The basic characteristics of permanent magnetic materials are as follows:

　　1. Remanence Br unit Gauss (Gs)

　　2. Coercive force Hcb and Hcj in Oe

　　3. Maximum magnetic energy product (BH) max

　　4. Curie temperature TC, unit ℃.

　　5. The maximum operating temperature (temperature coefficient).

　　2. NdFeB permanent magnet materials are the strongest and medium-priced good materials. At present, barium ferrite and strontium ferrite are the most widely produced and applied: cheap products. Alnico: the dominant position in pointer instruments.

　　Samarium Cobalt: Dominant in military supplies and high-end consumer goods. Platinum Cobalt: mainly used in aircraft black boxes, few products. NdFeB: It has been dominant in the electronic computer and its peripheral equipment, and the application in other aspects is becoming more and more extensive.

　　NdFeB material has the strongest magnetism and medium price. Under the protection of the surface coating, it has good stability, so it has the best development trend of expanding its use range.