one: English: coercivity: intrinsic coercive force Coercive force: Intrinsic coercivity
Two: the definition of what is called the coercive force and the intrinsic coercivity: Hcb, Hcj makes the magnetization to technology saturated B magnets (magnetic induction intensity) reduced to zero by the need to reverse the magnetic field strength is called the magnetic coercivity, similarly, the intrinsic magnetic induction intensity of UoM or Mr reduced to zero needed back to the strength of the magnetic field is called the intrinsic coercivity.
Three: the coercivity of permanent magnetic materials in the demagnetization curve, when the reverse magnetic field H increases to a value of bHc, the magnetic induction intensity B of the magnet is 0, called the reverse magnetic field H value for the material of the coercivity of bHc; in the reverse magnetic field H= bHc, magnet foreign not display flux, therefore the coercivity of bHc characterization of permanent magnetic material to resist external reverse magnetic field or other demagnetization effect ability. The coercivity of bHc is an important parameter in one of the magnetic circuit design. It is worth noting that the coercivity of remanence bHc is always less than Jr in value. In H= bHc, B=0 bHc, is 0 mu =J, already indicated above, the magnetic polarization intensity at any point on the demagnetization curve of J value is always less than the remanence Jr, the coercivity of bHc in value is always less than the remanence Jr. For example: Jr =12.3kGs magnet, the bHc may not be greater than 12.3kOe. In other words, Jr is the theoretical limit of the remanence coercivity bHc in value.
Four: the intrinsic coercivity: when the reverse magnetic field H= bHc, although the magnetic induction intensity B of the magnet is 0, the magnet flux vector foreign is not displayed, but the micro magnetic dipole moment magnet internal and tend not to 0, that is to say at this point magnetic polarization of J magnet in the original direction often remain a larger value. Therefore, the intrinsic magnetic properties of bHc are not sufficient to characterize the magnet; when the reverse magnetic field H increases to a value jHc, vector micro magnetic dipole moment magnet internal and 0, called the reverse magnetic field H values for the intrinsic coercivity of the material jHc.
The intrinsic coercivity of jHc is a very important physical parameter of permanent magnet material, magnet for jHc is much greater than bHc, when the reverse magnetic field H is greater than bHc but less than jHc, although at this time has been demagnetized magnet to the magnetic induction intensity B reverse degree, but withdrawn in reverse magnetic field H, the magnetic induction intensity B magnet can still because of microscopic magnetic dipole moment vector internal and in the original direction and the direction to the original. That is to say, as long as the reverse magnetic field H is not reached jHc, permanent magnetic material has yet to be fully demagnetization. Therefore, the intrinsic coercivity jHc is the characterization of permanent magnetic material to resist external reverse magnetic field or other demagnetizing effect, in order to maintain a main index to its original state of magnetization ability.
Five: unit and magnetic field intensity per unit of coercivity bHc and intrinsic coercivity jHc of the same. |
