The Magnetic production process
Beginning with rare earth ore, high purity rare earth
oxides are separated and refined.
Additives such as rare earth metals, iron, cobalt and
others are measured to produce the desired composition. The materials are then
melted in a vacuum induction furnace as shown below.
The materials are exposed to high frequency and melted
in an induction furnace.
After completion of various process steps, the ingots
are pulverized into particles that are several microns in size. In order to
prevent oxidation from occurring, the small particles are protected by nitrogen
and argon.
The magnetic particles are placed in a jig and a
magnetic field is applied while the magnets are pressed into shape. Through
this process, we achieve magnetic anisotropy.
Two methods of pressing exist: perpendicular pressing
where magnets are pressed in a perpendicular magnetic field and parallel
pressing where they are pressed in a parallel field. Given an equal grade of
magnet, the perpendicular press method will result in a higher performance
magnet. However, ring magnets must be pressed using the parallel method.
Ingots that have been pressed are heat treated in a
sintering furnace. The density of the ingots prior to sintering is about 50% of
true density but after sintering, the true density is 100%. Through this
process the ingots' measurement shrink by about 70%-80% and their volume is
reduced by about 50%.
Aging the magnets after sintering adjusts the
properties of the metals.
Basic magnetic properties are set after the sintering
and aging processes are complete. Key measurements including remnant flux density,
coercivity, and maximum energy product are recorded.
Only those magnets that pass the inspection are sent
to subsequent processes including machining and assembly.
Magnetic Technology
How do magnet function
A
magnet is any object that has a magnetic field. It attracts ferrous objects
like pieces of iron, steel, nickel and cobalt. In the early days, the Greeks
observed that the naturally occurring 'lodestone' attracted iron pieces. From
that day onwards began the journey into the discovery of magnets.
These
days magnets are made artificially in various shapes and sizes depending on
their use. One of the most common magnets - the bar magnet - is a long,
rectangular bar of uniform cross-section that attracts pieces of ferrous
objects. The magnetic compass needle is also commonly used. The compass needle
is a tiny magnet which is free to move horizontally on a pivot. One end of the
compass needle points in the North direction and the other end points in the
South direction.
The
end of a freely pivoted magnet will always point in the North-South
direction.
The
end that points in the North is called the North Pole of the magnet and the end
that points South is called the South Pole of the magnet. It has been proven by
experiments that like magnetic poles repel each other whereas unlike poles
attract each other.
Magnetic Fields
What
is a magnetic field? The space surrounding a magnet, in which magnetic force is
exerted, is called a magnetic field. If a bar magnet is placed in such a field,
it will experience magnetic forces. However, the field will continue to exist
even if the magnet is removed. The direction of magnetic field at a point is
the direction of the resultant force acting on a hypothetical North Pole placed
at that point.
How is a magnetic field created?
When
current flows in a wire, a magnetic field is created around the wire. From this
it has been inferred that magnetic fields are produced by the motion of
electrical charges. A magnetic field of a bar magnet thus results from the
motion of negatively charged electrons in the magnet.
Magnetic Lines Of Force
Just
as an electric field is described by drawing the electric lines of force, in
the same way, a magnetic field is described by drawing the magnetic lines of
force. When a small north magnetic pole is placed in the magnetic field created
by a magnet, it will experience a force. And if the North Pole is free, it will
move under the influence of magnetic field. The path traced by a North magnetic
pole free to move under the influence of a magnetic field is called a magnetic
line of force. In other words, the magnetic lines of force are the lines drawn
in a magnetic field along which a north magnetic pole would move.
The
direction of a magnetic line of force at any point gives the direction of the
magnetic force on a north pole placed at that point. Since the direction of
magnetic line of force is the direction of force on a North Pole, so the
magnetic lines of force always begin on the N-pole of a magnet and end on the
S-pole of the magnet. A small magnetic compass when moved along a line of force
always sets itself along the line tangential to it. So, a line drawn from the
South Pole of the compass to its North Pole indicates the direction of the magnetic
field.
Properties of the magnetic lines of force
- The magnetic
lines of force originate from the North Pole of a magnet and end at its
South Pole.
- The magnetic
lines of force come closer to one another near the poles of a magnet but
they are widely separated at other places.
- The magnetic
lines of force do not intersect (or cross) one another.
- When a magnetic
compass is placed at different points on a magnetic line of force, it
aligns itself along the tangent to the line of force at that point.
Neo Magnets
Neodymium is a rare earth type of permanent magnet made from an alloy of
neodymium, iron, and boron. Neo magnets are currently the strongest permanent
magnets known. It is also one of the most abundant of the rare earth elements.
Metro Aimante exports worldwide
The current range of our Neodymium Iron Boron magnets is as follows:
N27, N30, N33, N35, N38, N40, N42, N45, N48,
N50, N52, N30M, N33M, N35M, N38M, N40M, N42M, N45M, N48M, N50M, N30H, N33H,
N35H, N38H, N40H, N42H, N45H, N48H, N30SH, N33SH, N35SH, N38SH, N40SH, N42SH,
N45SH, N28UH, N30UH, N33UH, N35UH, N38UH, N40UH, N28EH, N30EH, N33EH, N35EH,
N38EH, N33VH/AH.
Metro Aimante manufacturer magnetic technology export
health products Trade & Information Centre Prague
Czech Republic
Export - Europe, Germany, Suisse,
France, Belgium, Holland, Denmark Sweden, Norway, Finland, Italy, Spain,
Greece, Romania, Czech Republic Slovenia, Russia, Poland ,Hungary, Bulgaria,
Latvia, Turkey, Morocco ,Swiss, Israel, Egypt, Jordan , India, USA, Canada,
South- America, South- Africa, North Africa, Middle-East ,Far East.
Technical and trade inquiry well come Metro
Aimante
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