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Glossary MAGNETIC TERMS
Curie temperature
Types of magnetization
Remanence (Br)
If the Curie temperature is reached, the magnetic material loses its magnetism.
Depending on the required application, model and material of the magnets, different types of magnetization are used. For example, with different magnetizations on the same model, differences can be achieved in the relationship between holding power and air gap. The raw magnet used is also an important factor. If this concerns anisotropic material, basically the first two types of magnetization shown above are relevant. The latter type of magnetization is generally used for isotropic magnets.
Remanence is the residual magnetization of a magnetic material magnetized up to saturation in a closed circle. Remanence is stated in Gauss (G), Tesla (T) or Millitesla (mT).
Operating temperature The operating temperature is the highest temperature to which a magnet can be exposed without suffering a permanent loss of its magnetic power. It is an approximate value because there is dependence to the dimensioning. There are factors, e.g. mechanical or chemical stress, which may further limit the maximum operating temperature.
S
N
N
Energy product (B Ă— H)max The maximum energy product of the flux density B and field strength H is the most important quality of a magnetic material. The higher the energy product, the greater the magnetic energy. The higher the (B Ă— H)max value of a magnetic material, the lower the magnetic volume required for a certain task with otherwise identical ratios.
Coercivity Hc Coercivity is the field force necessary to eliminate magnetization. The higher the value, the more resistant the magnetization. A distinction is made between HcB and HcJ.
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Axial magnetization through height. H N
N S
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N
N S
S N
Sector shaped magnetization axially magnetized through height.
N S
S N
N D
S Strip magnetization lateral on one side.
S N S