Neodymium

Neodymium-Iron-Boron (NdFeB) allows for very strong magnets at low cost. The production takes place via powder metallurgical processes, but today increasingly as plastic-bonded magnets. For a long time, the operating temperatures were limited to a maximum of 60 – 120 °C. With some recent developments, operating temperatures of up to 200 °C are specified. Magnetic material consisting of neodymium, iron, and boron.

What exactly are neodymium magnets?

A neodymium magnet is a particularly strong magnet. These super magnets are also known as neodymium iron boron magnets. Neodymium magnets - i.e., rare earths - are more expensive than conventional magnets due to their complex production technology. However, they are among the strongest of their kind. The largest deposits and explored reserves are in Asia, more precisely in China, where around 55,000,000 tons of the rare earths are currently suspected.

Areas of application for neodymium

Lanthanum (57La) and neodymium (60Nd), often referred to as "twins" in combination, are primarily and intensively used in metallurgy. Lanthanum is used, for example, as a cast iron and alloy additive to increase oxidation resistance. Neodymium, on the other hand, in combination with boron and iron, are currently the strongest known magnets for machines and rotors - for example in hybrid vehicles, wind turbines, loudspeakers and headphones.

China has an almost 100% monopoly on the world production of NdFeB magnets. In its natural form and in significant quantities, neodymium only occurs in the minerals monazite and bastnaesite and in rare earth metal alloys with iron and magnesium. In addition to the Chinese mines, the raw material also exists to a small extent in the Mount Weld ore deposit in Western Australia and in the Mountain Pass mine in San Bernardino County, California, which has been reactivated since 2010.

Neodymium is also required for computer hard drives and in glass coloring, but it is dominant in the production of so-called rare earth magnets. Scientifically, it is known with the abbreviation NdFeB and the incomparably high values in the parameters Curie temperature (310-400), energy density (200-440), coercive field strength (magnetic field, 750-2000) and remanent flux density (1.0-1.4). In popular parlance, the strong neodymium magnets are also referred to as super magnets or even death magnets. This lethal nickname stems not least from the frequent accidents that occur. This can happen with inattentive and improper handling, processing, and use of the powerful magnets, especially in the private sphere.
One hears and reads about bruises, injuries and the destruction of data carriers such as floppy disks, debit and credit cards or pacemakers due to the immense attraction of the NdFeB magnets. The chips and dust particles produced during processing can also easily ignite.

Safety when handling neodymium magnets

When storing and joint storage conditions, care must be taken to ensure that neodymium does not meet oxygen and nitrogen and is protected from moisture. In Germany it is also forbidden to store neodymium together with certain objects or substances:

  • Medicines
  • Groceries
  • Animal feed
  • Flammable substances
  • Toxic substances
  • Radioactive substances
  • Oxidizing substances
  • Self-reactive substances
  • Ammonium Nitrate
  • Organic peroxides

When disposing of neodymium and magnets made of NdFeB, it must be ensured that these represent hazardous waste according to the Waste List Ordinance (AVV), and residues should be recycled in collection containers for regenerable metal salt residues. When processing the flammable solid neodymium, the use of protective clothing and respiratory masks is generally recommended, open flames and sources of ignition as well as smoking are strictly prohibited.

Since they are also widely used as toys and decorative items, manufacturers and distributors also regularly and urgently warn of the dangers of accidental ingestion and potentially life-threatening intestinal perforation. Because of this increased risk, especially for children, the two states of Australia and New Zealand completely banned the import and trade of this type of toy magnet in 2012 and 2013.

Order neodymium in the magnet shop

At magnet-shop you will find a wide variety of models such as:

  • Hookmagnets
  • Telescopic magnets
  • Ringmagnets
  • Discmagnets

As a leading supplier, the company is particularly strong in the field of school and industrial magnets. The rodmagnet is used to make field lines (or lines of force) visible in school lessons. Iron powder is best suited for this visualization. The magnet color can be selected for many articles. The school classic is red/green (N/S). Magnets sold by magnet-shop can also be used, for example, on whiteboards, magnetic boards, as pinboard magnets or as office magnets.

Magnetic characteristics of neodymium magnets

Material
magnetization
grade

RemanenceCoercivityEnergy productMax.
Temperature
BrbHciHc(BxH)max
Gauss (G)Tesla (T)kOek/mkOek/mMGOekJ/m³°C
N30 10800-11200 1.08-1.12 9.8-10.5 780-836 ≥ 12 ≥ 955 28-30 223-239 ≤ 80
N33 11400-11700 1.14-1.17 10.3-11.0 820-876 ≥ 12 ≥ 955 31-33 247-263 ≤ 80
N35 11700-12100 1.17-1.21 10.8-11.5 860-915 ≥ 12 ≥ 955 33-35 263-279 ≤ 80
N38 12200-12600 1.22-1.26 10.8-11.5 860-915 ≥ 12 ≥ 955 36-38 287-303 ≤ 80
N40 12600-12900 1.26-1.29 10.5-12.0 860-955 ≥ 12 ≥ 955 38-40 303-318 ≤ 80
N42 12900-13200 1.29-1.32 10.8-12.0 860-955 ≥ 12 ≥ 955 40-42 318-334 ≤ 80
N45 13200-13700 1.32-1.37 10.8-12.5 860-995 ≥ 12 ≥ 955 43-45 342-358 ≤ 80
N48 13700-14200 1.37-1.42 10.8-12.5 860-995 ≥ 12 ≥ 955 45-48 358-382 ≤ 80
N50 14000-14600 1.40-1.46 10.8-12.5 860-995 ≥ 12 ≥ 955 47-51 374-406 ≤ 80
N52 14200-14700 1.42-1.47 10.8-12.5 860-995 ≥ 12 ≥ 955 48-53 380-422 ≤ 80
N30M 10800-11200 1.08-1.12 9.8-10.5 780-836 ≥ 14 ≥ 1114 28-30 223-239 ≤ 100
N33M 11400-11700 1.14-1.17 10.3-11.0 820-876 ≥ 14 ≥ 1114 31-33 247-263 ≤ 100
N35M 11700-12100 1.17-1.21 10.8-11.5 860-915 ≥ 14 ≥ 1114 33-35 263-279 ≤ 100
N38M 12200-12600 1.22-1.26 10.8-11.5 860-915 ≥ 14 ≥ 1114 36-38 287-303 ≤ 100
N40M 12600-12900 1.26-1.29 10.8-12.0 860-955 ≥ 14 ≥ 1114 38-40 303-318 ≤ 100
N42M 12900-13200 1.29-1.32 10.8-12.5 860-995 ≥ 14 ≥ 1114 40-42 318-334 ≤ 100
N45M 13200-13700 1.32-1.37 10.8-13.0 860-1035 ≥ 14 ≥ 1114 43-45 342-358 ≤ 100
N48M 13700-14200 1.37-1.42 10.8-12.5 860-995 ≥ 14 ≥ 1114 45-48 358-382 ≤ 100
N50M 14000-14600 1.40-1.46 10.8-12.5 860-995 ≥ 14 ≥ 1114 47-51 374-406 ≤ 100
N27H 10200-10600 1.02-1.06 9.5-10.1 756-804 ≥ 17 ≥ 1353 25-27 199-215 ≤ 120
N30H 10800-11200 1.08-1.12 10.1-10.6 804-844 ≥ 17 ≥ 1353 28-30 223-239 ≤ 120
N33H 11400-11700 1.14-1.17 10.3-11.0 820-876 ≥ 17 ≥ 1353 31-33 247-263 ≤ 120
N35H 11700-12100 1.17-1.21 10.8-11.5 860-915 ≥ 17 ≥ 1353 33-35 263-279 ≤ 120
N38H 12200-12600 1.22-1.26 10.8-11.5 860-915 ≥ 17 ≥ 1353 36-38 287-303 ≤ 120
N40H 12600-12900 1.26-1.29 10.8-12.0 860-955 ≥ 17 ≥ 1353 38-40 303-318 ≤ 120
N42H 12900-13200 1.29-1.32 10.8-12.0 860-955 ≥ 17 ≥ 1353 40-42 318-334 ≤ 120
N44H 13200-13600 1.32-1.36 10.8-13.0 860-1035 ≥ 17 ≥ 1353 42-44 334-350 ≤ 120
N45H 13200-13800 1.32-1.38 10.8-12.2 860-963 ≥ 17 ≥ 1353 43-46 342-366 ≤ 120
N48H 13700-14200 1.37-1.42 10.8-12.5 860-995 ≥ 17 ≥ 1353 45-48 358-382 ≤ 120
N27SH 10200-10600 1.02-1.06 9.5-10.1 756-804 ≥ 20 ≥ 1592 25-27 199-215 ≤ 150
N30SH 10800-11200 1.08-1.12 10.1-10.6 804-844 ≥ 20 ≥ 1592 28-30 223-239 ≤ 150
N33SH 11400-11700 1.14-1.17 10.3-11.0 820-876 ≥ 20 ≥ 1592 31-33 247-263 ≤ 150
N35SH 11700-12100 1.17-1.21 10.8-11.5 860-915 ≥ 20 ≥ 1592 33-35 263-279 ≤ 150
N38SH 12200-12600 1.22-1.26 10.8-11.5 860-915 ≥ 20 ≥ 1592 36-38 287-303 ≤ 150
N40SH 12600-12900 1.26-1.29 10.8-12.0 860-955 ≥ 20 ≥ 1592 38-40 303-318 ≤ 150
N42SH 12900-13200 1.29-1.32 10.8-12.0 860-955 ≥ 20 ≥ 1592 40-42 318-334 ≤ 150
N45SH 13200-13700 1.32-1.37 10.8-12.5 860-955 ≥ 20 ≥ 1592 43-45 342-358 ≤ 150
N25UH 9800-10200 0.98-1.02 9.2-9.6 732-764 ≥ 25 ≥ 1990 23-25 183-199 ≤ 180
N28UH 10400-10800 1.04-1.08 9.8-10.2 780-812 ≥ 25 ≥ 1990 26-28 207-233 ≤ 180
N30UH 10800-11200 1.08-1.12 10.1-10.6 804-844 ≥ 25 ≥ 1990 28-30 223-239 ≤ 180
N33UH 11400-11700 1.14-1.17 10.3-11.0 820-876 ≥ 25 ≥ 1990 31-33 247-263 ≤ 180
N35UH 11700-12100 1.17-1.21 10.8-11.5 860-915 ≥ 25 ≥ 1990 33-35 263-279 ≤ 180
N38UH 12200-12600 1.22-1.26 10.8-11.5 860-915 ≥ 25 ≥ 1990 36-38 287-303 ≤ 180
N40UH 12600-12900 1.26-1.29 10.5-12.0 860-955 ≥ 25 ≥ 1990 38-40 303-318 ≤ 180
N25EH 9800-10200 0.98-1.02 9.2-9.6 732-764 ≥ 30 ≥ 2388 23-25 183-199 ≤ 200
N28EH 10400-10800 1.04-1.08 9.8-10.2 780-812 ≥ 30 ≥ 2388 26-28 207-223 ≤ 200
N30EH 10800-11200 1.08-1.12 10.1-10.6 804-844 ≥ 30 ≥ 2388 28-30 223-239 ≤ 200
N33EH 11400-11700 1.14-1.17 10.3-11.0 820-876 ≥ 30 ≥ 2388 31-33 247-263 ≤ 200
N35EH 11700-12100 1.17-1.21 10.8-11.5 860-915 ≥ 30 ≥ 2388 33-35 263-279 ≤ 200

Material characteristics of neodymium magnets

Curie temperature 310 - 370 °C
Maximum operating temperature 60 - 230 °C
Temperature coefficient of remanence Br -0.0012 - -0.0010 /K
Temperature coefficient of coercivity iHc -0.006 /K
Thermal conductivity approx. 8.5 W/(m·K)
Specific heat approx. 440 J/(kg·K)
Thermal expansion coefficient ca. 5·10-6/K
Density 7,4 ... 7,5 g/cm³
Modulus of elasticity approx. 160 kN/mm²
Flexural strength approx. 250 N/mm²
Compressive strength ca. 900 N/mm²
Vickers hardness 560 ... 580
Specific electrical resistance ca. 1,6 Ω·mm²/m


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