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Anisotropic Magnet:
it is a magnet that has a favourite direction of
magnetic orientation, so that the magnetic
characteristics are optimal in that direction.
Coercive Force, HC:
it is the force of demagnetization, measure in
Oersted, needed to reduce the B induction to
zero, after the magnet has been previously taken
to saturation.
Curie Temperature:
it is the temperature at which the magnets are
not able to keep magnetization anymore.
Flux:
it is the condition that exists in a magnetized
and undergone to a force piece. This is
characterised by the fact that the electromotive
force is produced in a direction that surrounds
the flux at every moment. Flux unity: 1 Wb
(Weber) = 1 Vs (Volt per second) = B (A =
surface).
Gauss, Gs:
it is the density unity of magnetic flux of the
GSC system, the magnetic flux line per aligned
inch. The induction unity is Gauss in the GCS
system.
Hysteresis Curve:
it is a one sluice curve obtained by a material,
tracing and corresponding the magnetic induction
value, B (on the abscissa), against the force
magnetization, H (on the ordinate) = (B)max
Induction, B:
it is the magnetic flux for a normal sector of a
normal section to the flux direction. The
induction unity is Gauss in the GCS system.
Intrinsic Coercive Force, Hci:
it is an intrinsic capacity of a material to
resist the demagnetization. Its value is
measured in Oersted and it is correspondent to
null intrinsic induction of the material after
the saturation. The permanent magnets with the
high intrinsic coercive force are called
permanent magnets, that usually are associated
with a high stability of temperature.
Irreversible loss:
it is defined as a magnet partial
demagnetization caused by external causes or
other reasons. These loss can be recovered only
by remagnetisation. The magnet can be stabilised
to avoid performance variations caused by
irreversible losses.
Isotropic Magnets:
it is material of a magnet whose magnetic
properties are the same in any direction. They
can be therefore magnetised in any direction
without loss of magnetic characteristics.
Magnetic Force:
it is the magnetomotive force for length of an
unity in any point of a magnetic circuit.
Oersted unity is the magnetic force of the GCS
system.
Maximum Energy Product, (BH) max:
there is a point in the hysteresis loop where
the product magnetizes the H force and the B
induction reaching a maximum. The maximum value
is called the Maximum Energy Product. This point
is the magnet required value to program an
energy. This parameter is usually used to
describe how strong this permanent magnetic
material is. Its unity is Gauss Oersted. One
MGOe means 1.000.000 Gauss Oersted.
Oersted, Oe:
it is an unity to magnetize the force in the GCS
system. One Oersted is equal to 79.58 A/m in HE
system.
Remainder, Bd:
it is the magnetic induction that remains in a
magnetic circuit after the removal of an
application, magnetizing the force. If there is
an aerial difference in the circuit, the
remainder will be lower than the remaining
induction, Br.
Residual Induction, Br:
it is the value of the induction in a point of
the hysteresis loop, to whom the hysteresis wrap
crosses up, the one of the B axis to zero that
magnetizes the force. The Br is the product of
the maximum magnetic flux density of this
material without an external magnetic field.
Saturation:
it is a condition for which the induction of a
ferromagnetic material has reached its maximum
value with the applied increase, magnetizing the
force. All the magnetic flux are oriented in one
direction to the state of saturation.
Stability:
it is the capacity to resist a demagnetization
during an operation. This influence of
demagnetization can be caused by high or low
temperatures or by external magnetic fields.
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