The three elements of magnetic materials

- Feb 28, 2019-

The relationship among Br, Hcj, (BH) Max


The value of Br can be considered to indicate the height of the surface gauss of the magnetized magnetic parts; The value of Hcj can indicate the anti-demagnetization and temperature resistance ability of magnetic parts after magnetization. (BH) Max is the maximum value of the product of Br and Hcj, and its value directly indicates the performance of the magnet. At present, we have not detected a magnet binding NdFeB(BH) Max with an energy higher than 11.5 MGOe.


Generally speaking, in magnets with (BH) Max close to each other, Br is high while Hcj is low. High Hcj, low Br. We can not only determine the quality of the product by the value of (BH) Max, but also by whether the data of Br and Hcj is suitable for the product we need.


As we all know, under the same conditions, that is, the same size, the same number of poles and the same magnetizing voltage, the magnetic component with high magnetic energy product will obtain a high magnetic meter, but at the same (BH) Max value, the height of Br and Hcj has the following influence on the magnetization:


highBr , lowHcj : in the same magnetizing voltage, can get a higher magnetic table;

low Br , high Hcj : to get the same table magnetic, need to use a higher magnetizing voltage;


We cannot determine the mass of a magnet by the height of Br, Hcj, (BH) Max. Even under the condition of the same (BH) Max value, high Br value, low Hcj or vice versa shall be determined according to the use and magnetization requirements of the product.


For multipole magnetization, Br high Hcj low magnetic powder should be used. And for the magnetic tile, strong magnet manufacturers generally use high Hcj low Br magnetic powder, this is because the magnetic tile used in the motor in use to bear a large demagnetization current and overload.