The performance of magnetic materials in general, through its fourparameters can be expressed, namely, residual magnetic flux density (referred to as Br) Br (Gauss units Gs or mT mT, 1mT = 10Gs), coercivity Hcb (unit Oster Oe ), intrinsic coercive force Hcj (unit Oster Oe), the maximum energy product (BH) max (units of megabyte, high-Austrian MGOe), where Br, Hcj, (BH) max of three parameters is the most direct expression.
Br, Hcj, (BH) max relationship between the three  The size of Br is generally thought to show that magnetic pieces of the surface magnetic field after magnetizing the level; Hcj may specify the size of the magnetic pieces of magnetization and demagnetization resistance after the high and low temperature capacity; (BH) max is the maximum value of the product of Br and Hcj It directly shows the size of the magnetic properties of high and low. At present we have not detected bonded NdFeB (BH) max can be larger than 11.5 of the magnets.  In general, (BH) max similar to the magnet, Br Gao, Hcj on the low side; Hcj Gao, Br on the low side. We can not simply with (BH) max to determine the level of products, good or bad, depends on the level of Br and Hcj the suitability of the products we need.  Size does that indicate that the three materials, good or bad  We can not Br, Hcj, (BH) max of the high and low to determine their good or bad, it is necessary to use the product, the required characteristics to determine the level of the three; even in the same (BH) max value of the condition, but also look at the product use to determine the requirements of magnetizing high Br values, low Hcj, or the contrary.
Three size of the effects of magnetizing
We all know, under the same conditions, that is the same size, same pole number and the same magnetizing voltage, high energy product magnetic sheet obtained by magnetic pieces are also high, but at the same (BH) max value, Br, and Hcj the level of the magnetization have the following effects:
Br Gao, Hcj low: at the same magnetizing voltage, the table can get a higher magnetic;
Br low, Hcj high: To get the same table and magnetic, magnetizing need to use a higher voltage;
For a multi-polar magnetization, to adopt the high Br low Hcj magnetic,while for magnetic tile, the general Hcj high Br low magnetic, this is because the magnetic tile for the motor in use to bear the larger to the magnetic current and overload.