Neodymium Magnets

Tantalum 11/20/2018

1. Introduction of Neodymium Magnets:

Neodymium Magnets, (also known as NdFeB, NIB or Neo magnets), the most widely used type of rare earth magnets, are permanent magnets made from an alloy of neodymium, iron and boron to form the Nd2Fe14B tetragonal crystalline structure.
Neodymium Magnets are the strongest type of permanent magnets commercially available today.

When we mention the following synonyms typically we all mean Neodymium Magnets:
Neodymium Magnets
= Neodymium Iron Boron Magnets
= NdFeB Magnets
= NIB Magnets
= Neo (Rare Earth) Magnets
= Nd2Fe14B Magnets
= Strongest Magnets
= Strong Magnets

Neodymium Magnets have replaced AlNiCo Magnets and Ferrite Magnets  in many of the myriad applications in modern technology where strong permanent magnets are required, because their greater strength allows the use of smaller, lighter magnets for a given application, such as motors in cordless tools, hard disk drives and magnetic fasteners.

2. Product List of our Neodymium Magnets: Neodymium Magnets

3. What does Item No. stand for?

Products Information from Item Number, ALB-D42SH for example

ALB	-	D	4	2	SH
Company		Disc	Diameter: 4/16”	Thickness: 2/16”	Grade: N42SH

 

Item No. : ALB-D42SH

Product: Neodymium Disc Magnets

Grade: N42SH

Dimensions: 1/4" dia. x 1/8" thick

Magnetization Direction: Axial

Surface Plating: Ni-Cu-Ni

 

The symbol in item number:

 

Company	-	Shape	Size	Grade	Other
ALB	-	Disc: D Block: B Ring: R Sphere: R Arc: A	1: 1/16” 2: 2/16” …… 9: 9/16” A: 10/16” B: 11/16” C: 12/16” D: 13/16” E: 14/16” F: 15/16” X0: 1” X1: 1 1/16” Y0: 2” Z0: 3” ZX0: 4” ……	if not specified: Grade N42 SH: Grade N42SH N52: Grade N52 ……	DIA: Magnetization Direction is Diametrical S: magnetized with the south pole on the countersunk side. N: magnetized with the north pole on the countersunk side. P: Pair, one will have the north pole on the countersink side and one will have the south pole on the countersink side CS: countersunk DCS: countersunk on both sides PUR: Plastic-Rubber Coated MM: Mounting Magnets ……

4. How is Neodymium Magnet Produced?

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

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 whichare 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 densify 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.

5. Shapes of Neodymium Magnets:

Neodymium Magnets are available in Disc, Cylinder, Block & Bar, Cube, Ring & Tube, Sphere & Ball, Arc & Wedge in a wide range of shapes and sizes. ALB Materials Inc also custom-made shapes according to customer's requirements/drawings.

6. Grade of Neodymium Magnets:

Neodymium Magnets Grade

NdFeB Magnet 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
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
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

7. Coating/Plating of Neodymium Magnets:

Neodymium Magnets Coating:

8. Applications of Neodymium Magnets

Neodymium magnets can be used in following application: 
Benchtop NMR spectrometers
Drive motors for hybrid and electric vehicles. 
Electric generators for wind turbines 
Electric motors: Cordless tools
Electrical power steering
Erase heads for cheap cassette recorders
Head actuators for computer hard disks
Lifting and compressor motors
Locks for doors
Loudspeakers and headphones
Magnetic bearings and couplings
Mechanical e-cigarette firing switches
Servomotors
Spindle and stepper motors
Synchronous motors
Toys
Magnetic jewelry clasps
Children's magnetic building sets (and other neodymium magnet toys) 
as part of the closing mechanism of modern sport parachute equipment.
Magnetic resonance imaging (MRI) scanners
etc.

9. Read the magnet safety warnings before you purchase or use magnets

MAGNET SAFETY WARNING

 

Disclaimer: ALB Materials Inc neither assumes nor accepts any liability for damages resulting from the handling or use of magnets. With your purchase, the buyer confirms that you have read and understood the following warnings, the buyer agrees that he/she is responsible for all damages and injuries caused by the magnets, which include personal injuries , property damages and magnet damages. The buyer must agree with the terms before purchase. Pull forces we provide are estimates only and we are not responsible for any inaccuracy of magnet pull force. Please test the pull force before any usage.

 

1. BIG MAGNET WARNING NOTICE:

Neodymium magnets we sell are very strong. Handling them with care is necessary to prevent personal injuries, property damages and magnet damages.
Magnets the size of a 2 inch cube or larger can cause serious damage to fingers if caught between 2 magnets such as breaking bones or losing finger tips.

 

2. SMALL MAGNET WARNING NOTICE:

Small magnets pose a choking hazard and should never be swallowed or inserted into any part of the body. For safety purposes we include this warning to deter children from using/handling small magnets as they can be dangerous. Small magnets are considered a choking hazard that can result in death and should be treated as such. When confirming your order you the customer become fully responsible for the safety of children, animals and anyone else to come into contact with these magnets.

For more information, see the US Consumer Product Safety Commission's News Release and Magnets Information Center webpages linked below.

1. 16 CFR Part 1240 - http://www.ecfr.gov/cgi-bin/retrieveECFR?gp=1&SID=271341d1457a4e3afc811d9609e87ac0&ty=HTML&h=L&mc=true&r=PART&n=pt16.2.1240
2. News Release - http://www.cpsc.gov/en/Newsroom/News-Releases/2014/CPSC-Approves-Strong-Federal-Safety-Standard-for-High-Powered-Magnet-Sets-to-Protect-Children-and-Teenagers/
3. Magnets Information Center - http://www.cpsc.gov/en/Safety-Education/Safety-Education-Centers/Magnets

 

3. SAFETY HANDLING OF NEODYMIUM MAGNETS

Neodymium magnets are brittle; they can be broken or can splinter in a collision. One should wear gloves and protective glasses when handling these magnets, because splinters and/or spacers could disengage and fly from the magnets.
Normal Neodymium magnets will lose their magnetic properties if heated above 175°F (80° C). Higher temperature rare earth neodymium magnets are available in our company.
The strong magnetic fields of neodymium magnets can damage items such as television, computer monitors, credit cards, bank cards, computers, diskettes and other data carriers, video tapes, mechanical watches, hearing aids, loud speakers and VCRs. Pace-makers may be damaged or switch to "Test Mode" in the presence of a strong magnetic force, if a pace-maker or other electrical body implant is in use, keep a minimum of 3 feet distance.
Children should not be allowed to handle neodymium magnets as they can be dangerous. Small magnets pose a choking hazard and should never be swallowed or inserted into any part of the body.
Under no circumstances should you try to cut, saw or drill the Neodymium magnets! Not only would the magnet break, but the resulting dust from the magnet is very flammable. Neodymium magnets should never be burned, as burning them will create toxic fumes.

10. Permanent Magnets Handbook: permanent-magnets-handbook.pdf

Link to this article: https://www.albmaterials.com/knowledge/neodymium-magnets.html