NdFeB magnets are used in all aspects of our daily life. For example, household appliances, electric vehicles, and mechanical equipment commonly used in our lives will use rare earth strong NdFeB magnets. Do you know what characteristics they have? Let me share with you the performance parameters of NdFeB magnets.


NdFeB magnet performance

NdFeB magnet is a rare earth permanent magnet material based on the intermetallic compound Nd2Fe14B, the main components are rare earth elements neodymium (Nd), iron (Fe), boron (B). Among them, the rare earth element is mainly neodymium (Nd). In order to achieve different performances of NdFeB magnets, some other rare earth metals such as dysprosium (Dy) and praseodymium (Pr) can be used instead, and iron can also be replaced by other rare earth metals such as cobalt (Co) and aluminum (Al). The metal is partially substituted, and the content of boron is small, but it plays an important role in the formation of tetragonal crystal structure intermetallic compounds, making the compounds have high saturation magnetization, high uniaxial anisotropy and high Curie temperature.


The intrinsic coercivity jHc of NdFeB magnets is a very important performance parameter of NdFeB magnets for permanent magnet materials. For magnets whose jHc is much greater than bHc, when the reverse magnetic field H is greater than bHc but less than jHc, although at this time The magnet has been demagnetized to the extent that the magnetic induction intensity B is reversed, but after the reverse magnetic field H is cancelled, the magnetic induction intensity B of the magnet can still return to the original direction because the vector sum of the internal microscopic magnetic dipole moment is in the original direction.


The performance of sintered NdFeB magnets consists of three parts: the main name and two magnetic properties. The first part is the main name, which is composed of the chemical symbol ND of neodymium element, the chemical symbol FE of iron element and the chemical symbol B of boron element. The second part is the number before the line is the nominal value of the maximum energy product (BH) max of the material (in kj/m3), the third part is the number after the slash, and the coercive force value of the magnetic polarization (in KA/m3 One-tenth of m), the values are rounded to integers. Brand example: NdFeb380/800 means (BH) max is 366~398kj/m3, Hcj is 800KA/MR sintered NdFeB magnet.


NdFeB magnet surface treatment process: 1. Phosphating; 2. Inorganic salt passivation; 3. Electroplating; 4. Electrophoresis; 5. Vacuum deposition.


Sintered NdFeB magnets have good strong magnetic properties and are widely used in electronics, electrical machinery, medical equipment, toys, packaging, hardware machinery, aerospace and other fields. The more common ones are permanent magnet motors, speakers, magnetic separators, Computer disk drives, magnetic resonance imaging equipment instruments, etc.


NdFeB magnet performance parameter table


NdFeB magnet physical performance parameter table



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