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♦
Anisotropic Magnet:
A magnet having a preferred direction
of magnetic orientation, so that the magnetic characteristics are
optimum in that direction.
♦Coercive
force, Hc:
The demagnetizing force, measured in Oersted, necessary to reduce
observed induction, B to zero after the magnet has previously been
brought to saturation.
♦Curie
temperature:
The temperature at which the parallel alignment of elementary magnetic
moments completely disappears, and the materials is no longer able to
hold magnetization.
♦Flux:
The condition existing in a medium subjected to a magnetizing force.
This quantity is characterized by the fact that an electromotive force
is induced in a conductor surrounding the flux at any time the flux
changes in magnitude. The unit of flux in the GCS system is Maxwell. One
Maxwell equals one volt*seconds.
♦Gauss,
Gs:
A unit of magnetic flux density in the GCS system; the lines of magnetic
flux peer square inch.1 Gauss equals 0.0001 Tesla in the SI system.
♦Induction,
Br:
The magnetic flux per unit area of a section normal to the direction of
flux. The unit of induction is Gauss in the GCS system.
♦Intrinsic
Coercive Force, iHc:
An intrinsic ability of a material to resist demagnetization. Its value
is measured in Oersted and corresponds to zero intrinsic induction in
the material after saturation. Permanent magnets with high intrinsic
coercive force are referred as "Hard" permanent magnets ,which usually
associated with high temperature stability.
♦Maximum
Energy Product, (BH) max:
There is a point at the hysteresis Loop at which the product of
magnetizing force Hand induction B reaches a maximum. The maximum value
is called the Maximum Energy Product. At this point, the volume of
magnet material required to project a given energy into its surrounding
is a minimum. This parameter is generally used to describe how "strong"
this permanent magnet material is. Its unit is Gauss Oersted. One MGOe
means 1,000,000 Gauss Oersted.
♦Oersted,
Oe:
A unit of magnetizing force in GCS system.1 Oersted equals 79.58 A/m in
SI system.
♦Irreversible
Loss:
Defined as the partial demagnetization of a magnet caused by external
fields or other factors. These losses are only recoverable by
demagnetization. Magnets can be stabilized to prevent the variation of
performance caused by irreversible
♦Polymer_
Bonding:
Magnet powders are mixed with a polymer carrier matrix, such as epoxy.
The magnets are formed in a certain shape, when the carrier is
solidified.
♦Residual
Induction, Br:
A value of induction at the point at Hysteresis Loop, at which Hysteres
is loop crosses the B axis at zero magnetizing force. The Br represents
the maximum magnetic flux density output of this material without an
external magnetic field.
♦Saturation:
A condition under which induction of a ferromagnetic material has reach
its maximum value with the increase of applied magnetizing force. All
elementary magnetic moments have become oriented in one direction at the
saturation status.
♦Sintering;:
The bonding of powder compacts by the application of heat to enable one
or more of several mechanisms of atom movement into the particle contact
interfaces to occur; the mechanisms are: viscous flow, liquid phase
solution-precipitation, surface diffusion, bulk diffusion, and
evaporation-condensation. Densification is a usual result of sintering.
♦Stability
:
An ability to resist to demagnetizing influence expected to be
encountered in operation. These demagnetizing influences can be caused
by high or low temperatures or by extremely magnetic fields.
♦Demagnetization
Curve:
The second quadrant of the hysteresis loop, generally describing the
behavior of magnetic characteristics in actual use, Also known as the
B-H curve.North Pole: That pole of a magnet which, when freely
suspended, would point to the north magnetic pole of the earth. The
definition of polarity can be a confusing issue,
and it is often best to clarify by using "north seeking pole" instead of
"north pole" in specifications
♦Magnetized
direction:
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