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Magnets Handbook
1. Introduction
2. Magnetic Materials
2.1 Neodymium Magnets - Rare Earth Magnets
2.2 SmCo Magnets - Rare Earth Magnets
2.3 AlNiCo
2.4 Ceramic
3. Magnetic Grades
4. Working Temperatures
5. Platings & Coatings
6. Magnetic Orientations
7. Manufacturing Processes
8. Measuring Magnets
8.1 Magnetic Moment and BH-Curves
8.2 Flux Density
8.3 Pull Force
9. Magnets Packaging
10. Magnets Handling
11. Applications
12. Definitions and Terminology
13. Conversions
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1. Introduction
This handbook is designed to provide the fundamental basics of magnetic materials, magnets
properties, methods of manufacture, and costing so that the user has adequate knowledge when
deciding what type or grade of material should be used in various applications.
Magnets are mainly used to help in the conversion of energy.
For example:
Mechanical to Electrical, such as in generators, sensors and microphones
Electrical to Mechanical, such as in motors, actuators and loudspeakers
Mechanical to Mechanical, such as for couplings, bearing and holding devices
There are four major types of permanent magnet materials:
NdFeB, Neodymium or Neo Rare Earth
SmCo, Samarium Cobalt
Ceramics, Ferrites (SrFe2O3 etc.)
AlNiCo, Alnico magnets
2. Magnetic Materials
2.1 Neodymium Magnets - Rare Earth Magnets
Neodymium iron boron (Nd2Fe14B), also known as Neo or NIB, is a type of rare earth magnetic
material. NdFeB is the strongest and most controversial magnets. They are in the rare earth
family because of the Nd, B, Dy, Ga elements in their composition.
NdFeB magnets have the highest energy approaching 52MGOe. Unprotected NdFeB magnets
are subject to corrosion. Coating/Plating are developed to overcome this disadvantages.
Coating/Plating materials include nickel, copper, silver, gold, zinc, tin and epoxy resin etc.
Typical coating is NiCuNi (Nickel).
2.2 SmCo Magnets - Rare Earth Magnets
Samarium Cobalt (SmCo), also known as Sm-Co, is a type of rare earth magnetic material.
They are in the rare earth family because of the Sm, Co elements in their composition.
Magnetic properties are high and they have very good temperature characteristics. They are also
more expensive than the other magnet materials. They come mostly in two grades: SmCo5 and
Sm2Co17, also known as SmCo 1:5 and 2:17. Common uses are in aerospace, military and
medical industries.
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2.2 Ceramic
Ceramics Magnets, also known as Ferrites, have been in production since the 1950's. They are
primarily made from Iron Oxide (FeO) and the addition of Sr and Ba through a calcining
process. They are the least expensive and most common of all magnet materials. Primary grades
are C1, C5 and C8. They are mostly used in motors and sensors.
2.3 AlNiCo
AlNiCo magnets are one of the oldest commercially available magnets and have been
developed from earlier versions of magnetic steels. Primary composition is Al, Ni and Co.
Although they have a high remanent induction, they have relatively low magnetic values
because of their easy of demagnetization. However, they are resistant to heat and have good
mechanical features. Common applications are in measuring instruments and high temperature
processes such as holding devices in heat treat furnaces.
3. Magnetic Grades
Neodymium Magnets Grade
Type Grade Residual
Induction
/BR(Gauss)
Coercive
Force/Hc
(Oe)
Intrinsic
Coercive
Force/Hci (Koe)
Max.Energy
Product/Bhmax
(MGOe)
Maximum
Operating Temp
(°C/°F)
Curie
Temp
(°C/°F)
N N35 11700 10900 12 35 80/176 310/590
N N38 12200 11300 12 38 80/176 310/590
N N40 12500 11400 12 40 80/176 310/590
N N42 12800 11500 12 42 80/176 310/590
N N45 13200 11600 12 45 80/176 310/590
N N48 13800 11600 12 48 80/176 310/590
N N50 14000 10000 11 50 60/140 310/590
N N52 14300 10000 11 52 60/140 310/590
M N33M 11300 10500 14 33 100/212 340/644
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M N35M 11700 10900 14 35 100/212 340/644
M N38M 12200 11300 14 38 100/212 340/644
M N40M 12500 11600 14 40 100/212 340/644
M N42M 12800 12000 14 42 100/212 340/644
M N45M 13200 12500 14 45 100/212 340/644
M N48M 13600 12900 14 48 100/212 340/644
M N50M 14000 13000 14 50 100/212 340/644
H N35H 11700 10900 17 35 120/248 340/644
H N38H 12200 11300 17 38 120/248 340/644
H N40H 12500 11600 17 40 120/248 340/644
H N42H 12800 12000 17 42 120/248 340/644
H N45H 13200 12100 17 45 120/248 340/644
H N48H 13700 12500 17 48 120/248 340/644
SH N35SH 11700 11000 20 35 150/302 340/644
SH N38SH 12200 11400 20 38 150/302 340/644
SH N40SH 12500 11800 20 40 150/302 340/644
SH N42SH 12800 12400 20 42 150/302 340/644
SH N45SH 13200 12600 20 45 150/302 340/644
UH N28UH 10200 9600 25 28 180/356 350/662
UH N30UH 10800 10200 25 30 180/356 350/662
UH N33UH 11300 10700 25 33 180/356 350/662
UH N35UH 11800 10800 25 35 180/356 350/662
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UH N38UH 12200 11000 25 38 180/356 350/662
UH N40UH 12500 11300 25 40 180/356 350/662
UH N42UH 12800 11300 25 42 180/356 350/662
EH N28EH 10400 9800 30 28 200/392 350/662
EH N30EH 10800 10200 30 30 200/392 350/662
EH N33EH 11300 10500 30 33 200/392 350/662
EH N35EH 11700 11000 30 35 200/392 350/662
EH N38EH 12200 11300 30 38 200/392 350/662
EH N40EH 12500 11300 30 40 200/392 350/662
AH N28AH 10400 9900 33 28 230/446 350/662
AH N30AH 10800 10300 33 30 230/446 350/662
AH N33AH 11300 10600 33 33 230/446 350/662
AH N35AH 11700 11000 33 35 230/446 350/662
AH N38AH 12200 11300 33 38 230/446 350/662
Samarium Cobalt Magnets Grade
Mat
erial
s
Type Gr
ade
Residual
Induction/BR
(Gauss)
Coercive
Force/Hc
(Oe)
Intrinsic
Coercive
Force/Hci
(Koe)
Max.Energy
Product/Bhma
x (MGOe)
Maximum
Operating Temp
(°C/°F)
Curie
Temp
(°C/°F)
Sm1
Co5
N 16 8100 7800 15 16 127/260 482/899
N 18 8500 8300 15 18 143/289 482/899
N 20 9000 8500 15 20 167/332 482/899
N 22 9200 8900 15 22 175/347 482/899
N 24 9600 9200 15 24 190/374 482/899
NS 16
S 7900 7700 23 17 135/275 482/899
NS 18
S 8400 8100 23 19 151/303 482/899
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NS 20
S 8900 8600 23 21 167/332 482/899
NS 22
S 9200 8900 23 23 183/361 482/899
NS 24
S 9600 9300 23 25 199/390 482/899
NX 10
X 6200 6100 23 11 88/190 572/1061
Sm2
Co1
7
NL 24
L 9500 6800 8-12 24 191/375 482/899
NL 26
L 10200 6800
8-12 26 207/404 482/899
NL 28
L 10500 6800
8-12 28 220/428 482/899
NL 30
L 10800 6800
8-12 30 240/464 482/899
NL 32
L 11000 6800
8-12 32 255/491 482/899
NM 26
M 10200 8500 12-18 26 207/404 572/1061
NM 28
M 10500 8500
12-18 28 220/428 572/1061
NM 30
M 10800 8500
12-18 30 240/464 572/1061
NM 32
M 11000 8500
12-18 32 255/491 572/1061
N 24 9500 8700 18 24 191/375 572/1061
N 26 10200 9400 18 26 207/404 572/1061
N 28 10500 9700 18 28 220/428 572/1061
N 30 10800 9900 18 30 240/464 572/1061
N 32 11000 10200 18 32 255/491 572/1061
NH 24
H 9500 8700 25 24 191/375 662/1223
NH 26
H 10200 9400 25 26 207/404 662/1223
NH 28
H 10500 9700 25 28 220/428 662/1223
NH 30
H 10800 9900 25 30 240/464 662/1223
NH 32
H 11000 10200 25 32 255/491 662/1223
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NX 22
X 9400 8400 15-20 22 175/347 572/1061
Ceramic/ Ferrite Magnets Grade
Materi
als
T
y
p
e
Grade
Residual
Induction/B
R(Gauss)
Coercive
Force/Hc
(Oe)
Intrinsic
Coercive
Force/Hci
(Koe)
Max.Energy
Product/Bhmax
(MGOe)
Maximum
Operating
Temp (°C/°F)
Curie
Temp
(°C/°F)
Ferrite N C1 2200 1860 3.25 1.05 300/572 450/842
Ferrite N C5 3800 2400 2.5 3.4 300/572 450/842
Ferrite N C7 3400 3250 4 2.75 300/572 450/842
Ferrite N C8 3850 2950 3.05 3.5 300/572 450/842
Ferrite N C10 4200 2950 3.51 3.82 300/572 450/842
AlNiCo Magnets Grade
Type Grade
Residual
Inductio
n/BR
(Gauss)
Coercive
Force/Hc
(Oe)
Intrinsic
Coercive
Force/Hc
i (Koe)
Max.Energy
Product/Bhmax
(MGOe)
Maximum
Operating
Temp (°C/°F)
Curie
Temp
(°C/°F)
Sintered
Isotropic *FLN8 5200 540 0.5 1.0-1.25 250/480 450/842
Sintered
Isotropic *FLNG12 7000 540 0.5 1.5-1.75 250/480 450/842
Sintered
Isotropic
*FLNGT1
4 5700 980 0.95 1.75-2.0 250/480 450/842
Sintered
Isotropic
*FLNGT1
8 5600 1130 1.1 2.25-2.75 250/480 450/842
Sintered
Anisotropic FLNG28 10500 590 0.58 3.5-4.15 250/480 450/842
Sintered
Anisotropic FLNG34 11000 640 0.63 4.3-4.8 250/480 450/842
Sintered
Anisotropic FLNGT28 10000 710 0.7 3.5-3.8 250/480 450/842
Sintered
Anisotropic FLNGT3 17800 1130 1.3 3.9-4.5 250/480 450/842
Sintered
Anisotropic FLNG33J 6500 1880 1.7 4.15-4.5 250/480 450/842
Sintered
Anisotropic FLNGT38 8000 1580 1.55 4.75-5.3 250/480 450/842
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Sintered
Anisotropic FLNGT42 8800 1530 1.5 5.3-6.0 250/480 450/842
Cast
Isotropic *LN96 800 380
1.13 250/480 450/842
Cast
Isotropic *LN10 6000 500
1.2 250/480 450/842
Cast
Isotropic *LNG12 7200 500
1.5 5250/480 450/842
Cast
Isotropic *LNG13 7000 600
1.6 250/480 450/842
Cast
Anisotropic LNG37 12000 600
4.65 250/480 450/842
Cast
Anisotropic LNG40 12500 600
5 250/480 450/842
Cast
Anisotropic LNG44 12500 650
5.5 250/480 450/842
Cast
Anisotropic LNG52 13000 700
6.5 250/480 450/842
Cast
Anisotropic LNG60 13500 740
7.5 250/480 450/842
Cast
Anisotropic LNGT28 10000 720
3.5 250/480 450/842
Cast
Anisotropic LNGT36J 7000 1750
4.5 250/480 450/842
Cast
Anisotropic LNGT52J 9000 1750
6.5 250/480 450/842
Cast
Anisotropic *LNGT18 5800 1250
2.2 250/480 450/842
Cast
Anisotropic LNGT32 8000 1250
4 250/480 450/842
Cast
Anisotropic LNGT40 8000 1380
5 250/480 450/842
Cast
Anisotropic LNGT60 9000 1380
7.5 250/480 450/842
Cast
Anisotropic LNGT72 10500 1400
9 250/480 450/842
Cast
Anisotropic LNGT88 11000 1500
11 250/480 450/842
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4. Maximum Working Temperatures
The following table shows different magnetic materials and their maximum working
temperatures.
Maximum Working Temperature
Material ℃ ℉
NdFeB N 80 176
NdFeB M 100 212
NdFeB H 120 248
NdFeB SH 150 302
NdFeB UH 180 356
NdFeB EH 200 392
Sm1Co5 260 500
Sm2Co17 350 662
AlNiCo 540 1004
Ferrite 400 752
5. Plating & Coatings
There are various plating/coating available for permanent magnets. Samarium cobalt, AlNiCo
and Ferrite magnets are not prone to corrosion. NdFeB magnets are prone to corrosion and need
plating/coating in most conditions. Typical plating/coating for NdFeB magnets is nickel or Ni-
Cu-Ni. Nickel-copper-nickel(Ni-Cu-Ni) plating has proved to be one of the most corrosion
resistant and durable types of plating. Magnets can also be coated with organic coatings such as
epoxy resins. Magnets Plating & Coatings
Magnets Plating & Coatings
Ni-Cu-Ni Double Ni Epoxy
Ni Black Ni Phosphating
Cu White Zn Plastic
Au Color Zn Rubber
Ag Sn Teflon (PTFE)
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6. Magnetic Orientations
A magnet can be magnetized in a variety of directions. Anisotropic materials must be
magnetically oriented during production. Therefore are inclined to a fixed orientation.
Disc & Cylinder Magnets, Ring & Tube Magnets
Axially Magnetized Diametrically Magnetized
Block & Bar & Cube Magnets Sphere & Ball Magnets
Magnetized Through Thickness Axially Magnetized
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Arc & Wedge Magnets
7. Manufacturing Processes
Production Process of Neodymium Magnets:
1) Vacuum Melting
Compositions of neodymium, iron, iron-boron, dysprosium and minor additions including
cobalt, copper, gallium, aluminum and others are mixed and induce-melted to form
Nd2Fe14B phase and other necessary structures required for high performance permanent
magnets. The melting temperature reaches over 1300o C. Usually repeated melting is
needed to produce an even phase and structure distribution.
2) Crushing
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The ingots from the vacuum melting process are crushed into coarse powder directly, or
strip cast followed by HDDR processing into coarse powder.
3) Jet Milling
The coarse powder further milled into required particles sized about 3 microns in diameter
by a jet miller. Those particles become single-domain and anisotropic which are critical for
producing a high coercivity magnet. Jet milling is the most effective way to mill the
particles so far.
4) Pressing
Compact the fine powder to produce block magnets. Usually a magnetic field is applied
during pressing to align those anisotropic particles in order to produce maximum magnetic
output in a particular direction. There are two pressing methods, transverse and axial,
depending on different applications. Isostatic pressing is normally used to further density
magnets to 75-80%.
5) Vacuum Sintering
The compacted magnets are sintered at temperatures above 1000 o C and for many hours to
be solidified and compacted further more up to 99% by shrinking it's body. A required
microstructure between particles for high performance permanent magnets is also formed in
this stage. Some following heat-treatments are needed to stabilize the magnets.
6) Machining
Shrinkage and distortion during sintering is too difficult to control adequately and magnets
normally need at least a “ clean up” grind on the surface. Small parts are cut or sliced
precisely to form a big block to meet the demanding tolerances and different shapes.
7) Surface Treatment
Various surface treatments can be applied on the final products. They include zinc, nickel,
Ni-Cu-Ni multi-layer, e-coating, epoxy and others. They provide different surface finishing,
appearance and corrosion resistance, applicable to different application environments.
8) Inspection
This is the final step. Magnets are inspected based on customer specifications and needs,
including dimensional and magnetic tests.
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8. Measuring Magnets
8.1 Magnetic Moment and BH-Curves
The magnetic moment is a measure of the strength of a magnetic source. Using a fluxmeter and
a helmholtz coil, the magnetic moment of a particular permanent magnet can be determined.
From the magnetic moment, the operating flux desity (Bd), operating field strength (Hd),
coercive force (Hc), residual flux density (Br) and maximum energy product (BHmax) can be
derived.
8.2 Flux Density
The measurement of flux density is made using a gauss/tesla meter. Generally this simple
measurement is made at the surface of the magnet. Most gauss meters use a hall effect sensor to
produce a flux density measurement. The gauss meter provides a constant input current to the
hall sensor which then produces an output voltage that is proportional to the density of the
magnetic field passing through it. The resulting measurement is usually expressed as gauss or
tesla.
8.3 Pull Force
Pull force measurements are a mechanical method of obtaining a measurement of the holding or
pulling strength of a magnet. In this measurement test, a magnet is attached to an actuator with
an integrated strain gauge. The opposite side of the magnet is attached to a fixed piece of
ferromagnetic material such as a plate of mild steel. As the actuator forces the magnet from the
steel plate, the force needed to separate the two is recorded by the strain gauge. Pull force tests
are not standardized and pull force values provided by manufacturers vary widely and should
not be used as the basis of final magnet selection.
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9. Magnets Packing
Magnets are normally shipped in steel lined boxes to shield the magnetic flux from the outside
of the box. In actually, the steel provides a circuit or path for the flux to move. Magnetic flux
can only be redirected it can never really be adsorbed or blocked.
Strong magnets may require separate packaging or spacers to provide a buffer space between
the magnets. These spacers allow the magnets to be separated and more easily handled. In
addition to spacers between magnets, boxes of magnets may require rigid material between the
boxes to prevent the boxes from attracting each other.
10. Magnets Handling
Magnets are produced in a wide array of sizes, shapes, and strengths, but there are similarities
between all magnetic materials. They are all relatively brittle which when coupled with their
magnetic strength present a number of issues.
Handling concerns are common for many our customers, whether it’s in protecting the magnets
or the individuals that are using the magnets. The lack of familiarity in using magnets is quite
common among receiving and inspection personnel.
The two primary issues resulting from incorrect handling are personal injury and damaged
magnets. Personal injury can result in a variety of ways. Strong magnets can draw ferrous
objects or other magnets towards them with surprisingly strong forces resulting in sharp
fragments and pinching hazards. This can happen so fast that the human body is unable to stop
the collision. This action is sudden and will typically catch untrained or uninformed technicians
by surprise. Magnetic fields can also negatively impact people with pacemakers or other
implanted medical devices. Although magnets and magnetic fields are around all of us every
day, we are not always aware of the strength of industrial magnets. People with implanted
medical devices should avoid handling magnets without previously consulting their doctor.
The second opportunity for an issue is damage to the magnets or actually losing the magnet.
Magnets can be damaged both physically and magnetically. Some alloys will lose their
magnetism when not handled properly. Always keep and store the magnets in the manner in
which they were received from the magnet supplier. This will help ensure the magnets do not
chip, get broken, or become demagnetized. The other issue to the magnet is that it can be easily
lost because they attract to ferrous objects.
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We employ a number of techniques to mitigate handling issues that arise from time to time.
When it comes to packaging you should never be concerned about the magnets arriving in a
safe manner. We’ve developed various packaging methods that mean you’ll receive your order
of magnets packaged appropriately for transit, storage, and ultimately safe removal. As a
producer of very powerful magnets and magnetic assemblies, there are occasional and
unavoidable situations that involve risk to either the magnet or the persons working with the
magnets. By default, extreme caution should be practiced when working with all magnets
regardless of one’s familiarity when them. Our commitment is to provide the highest level of
service which includes educating our customers on safe handling procedures and practices. We
urge all of our customers to contact us with any questions regarding handling or storage of our
magnetic products.
Please read the magnet safety warnings before you purchase or use magnets: Magnets Safety
Warnings (https://www.albmagnets.com/magnets-safety-warnings.html)
11. Applications
Machinery and drive engineering:
Electric motors, textile machines, brakes, drive couplings (permanently magnetic), robots
Electrical engineering:
Hall sensor technology, Reed switch, relay, electric tools, proximity sensors
Automotive engineering:
Antilock braking system, tachometers, window regulators, central locking system, wipers,
airbag
Power engineering:
Windmills, dynamos, generators
Conveyer technology:
Pumps, lifts, conveyor bands
Aeronautical and aerospace engineering:
Navigation, control systems, physical facilities
Measurement and regulation technologies:
Scales, magnetic valves, gas, water and electric meters, level measurement
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Organization and control technologies:
Warehouse labeling, organization, packaging
Medical engineering:
Magnetic resonance tomography
Textile sector:
Magnetic closures
Telecommunication:
Televisions, microphones, telephones, headsets, loudspeakers
Model making:
For the construction of electric motors, cleaning of rails, sensor technology, automation
Furniture production:
Opening mechanisms, supporters
Office requirements:
Pin boards, classification systems, name badges
Garage and Hobby:
Cleaning of motor oil, find and recover objects, fixation of tools and devices, removal of bumps,
fixation of objects
Household:
Pin board, delete media (hard disks, audiotapes, videotapes, cash cards), removal of swarfs
Research and school:
Experiments, atom model
Games and handicraft:
Jewelry, magnetic curtain, decorative magnets, gift ideas, legerdemains
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12. Definitions and Terminology
1. Anisotropic Magnet
A magnet having a preferred direction of magnetic orientation, so that the magnetic
characteristics are optimum in that direction.
2. 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.
3. Curie temperature, Tc
The temperature at which the parallel alignment of elementary magnetic moments
completely disappears, and the materials are no longer able to hold magnetization.
4. 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 x seconds.
5. Gauss, Gs
A unit of magnetic flux density in the GCS system; the lines of magnetic flux per square
inch. 1 Gauss equals 0.0001 Tesla in the SI system.
6. Hysteresis Loop
A closed curve obtained for a material by plotting corresponding values off magnetic
induction, B (on the abscissa), against magnetizing force, H (on the ordinate).
7. Induction, B
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, Hci: 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.
8. Intrinsic Coercive Force, Hci
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.
9. Irreversible Loss
Defined as the partial demagnetization of a magnet caused by external fields or other factors.
These losses are only recoverable by remagnetization. Magnets can be stabilized to prevent
the variation of performance caused by irreversible losses.
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10. Isotropic Magnets
A magnet material whose magnetic properties are the same in any direction, and which can,
therefore, be magnetized in any direction without loss of magnetic characteristics.
11. Magnetic Flex
The total magnetic induction over a given area.
12. Magnetizing Force
The magnetomotive force per unit length at any point in a magnetic circuit. The unit of the
magnetizing force is Oersted in the GCS system.
13. Maximum Energy Product, (BH)max
There is a point at the Hysteresis Loop at which the product of magnetizing force H and
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.
14. Oersted, Oe
A unit of magnetizing force in the GCS system. 1 Oersted equals 79.58 A/m in SI system.
15. Permeability, Recoil
The Average slope of the minor hysteresis loop.
16. Rare Earths
A family of elements with an atomic number from 57 to 71 plus 21 and 39. They are
lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium,
dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium, and yttrium.
17. Remenance, Bd
The magnetic induction which remains in a magnetic circuit after the removal of an applied
magnetizing force. If there is an air gap in the circuit, the remenance will be less than the
residual induction, Br.
18. Reversible Temperature Coefficient
A measure of the reversible changes in flux caused by temperature variations.
19. Residual Induction, Br
A value of induction at the point at Hysteresis Loop, at which Hysteresis 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.
20. Saturation
A condition under which induction of a ferromagnetic material has reached its maximum
value with the increase of applied magnetizing force. All elementary magnetic moments
have become oriented in one direction at the saturation status.
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21. 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.
22. Surface Coatings
Unlike Samarium Cobalt, Alnico and ceramic materials, which are corrosion resistant,
Neodymium Iron
13. Conversions
Reading G mT Oe kA/m
1 G Gauss − 0.1 1 0.07977
1 mT milli Tesla 10 − 10 0.7977
1 Oe Oersted 1 0.1 − 0.07977
1 kA/m kilo Ampere
per meter 12.54 1.254 12.54 −