Neodymium-Iron-Boron magnets (NdFeB)

Rare earth magnets, thanks to their properties, although they are rare on our planet, are essential for the production of special equipment and everyday technology that let the market demand increase. Among the rare earths with special value there are also some of them with mystical value like platin, gold and silver.

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 Neodymium magnet and their "dirty story"

Over 40 years ago, the end of colonialism and the beginning of the clashes about raw materias inspired the novel by the British writer Eric Ambler Clifford (1909-1998) "Dirty story" (1967).
In this story scandium, yttrium, cerium, praseodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium and lanthanum and neodymium are the main characters involved in a conflict with neighboring states, mercenaries and mine operators. With the development of digital information and communication, the global demand for rare earths has risen increasingly and rapidly.
Unlike the novel, the largest deposits of rare metals is not in Africa, but in Asia. Especially in China, where the amount is estimated to approximately 55 million tons of metals and rare earths.

 

Magnets, mines, minerals, monopolies and a million possibilities

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The mentioned elements are present mainly in nuclear reactors and fuel cells. In chemistry for reduction processes, cleaning and as contrast agents in magnetic resonance and for the construction of radar and plasma screens, in lasers, fluorescent lights, LCD and LED, and many other products. The last two elements are said to be "twins", in fact lanthanum (57La) and neodymium (60Nd) and are vastly used in metallurgy.
Lanthanum as cast iron or as an additional element to metal alloys helps to increase the oxidation resistance. Neodymium is used instead in combination with boron and iron for the production of strong magnets, which are used in cars-engine rotors (hybrid cars) and in mills for wind energy production.
China has almost a complete monopoly in terms of world production of neodymium magnets. In its natural state and in a sufficient amount, neodymium was found only in rocky minerals of monazite and bastnaesite in combination with iron and magnesium. This raw material is located outside of China too: in Mount Weld in Western Australia although in smaller quantities, and in Mountain Pass mine in San Bernardino County, California.

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That is a really strong magnetic field!

Neodymium is also used for the construction of hard disks and optical fibers. The production, however, concerns all rare earth magnets. Scientifically they are indicated with NdFeB and with high values ​​incomparable regarding the Curie temperature (310-400), energy density (200-440), the coercivity of the magnetic field (750-2000) and remanence (1.0-1.4).
Generally these are called super magnets or even death magnet. This name comes from the frequent accidents caused by an improper use and the distraction of the person who uses them (especially at home). There are frequent reports of bruises and injuries or destruction of data storage media such as floppy disks, credit cards or pacemakers through the immense magnetic field. Even improper processing can be dangerous because the splinters and dust are flammable.

Tips for storage and use

For the preservation of neodymium magnets is important not to put them in contact with oxygen and CO2 and in humid environments. In Germany the storage in contact with medicines, food and feedstuffs, combustible, poisonous, radioactive, explosive, flammable, oxidizing and self-reactive substances is illegal. The same for gases and aerosols, as well as ammonium nitrate and organic peroxides.
For the disposal of neodymium magnets it is necessary to consult the European Waste Catalogue (EWC), and put them in a special container that reuses metal alloys. During processing and use is recommended a suitable safety clothing as well as the use of a mask. The use of fire or smoke is prohibited.

The result of international cooperation

Because of their use in many fields and also in the toys industry and decorative items, manufacturers and distributors warn about the dangers of accidental ingestion. This could lead to intestinal perforation. Especially children risk ingestion. For this cause Australia and New Zealand have banned the import and trade of toys of this kind, respectively, in 2012 and in 2013.
In accordance with the instructions and information provided in the last paragraph, there are indications by the United States automotive group General Motors with the corporate group Japanese Sumitomo Group that confirm neodymium magnets can be used without problems. These should not be totally welded but only glued using special glues.
In addition to the standard models we offer many models that have a plastic or a metal base with many mounting options. These are used mainly in the field of fashion as a closure for bags and accessories, or in the field of design for a discrete furniture closure possibility.
The incomparable quality of these magnets are their low weight, high holding forces, almost no loss of magnetic force and high weather resistance. The maximum temperatures endured by the magnets were in the past about 60-120 ° C, today thanks to the search may be increased up to 200 ° C. This temperature is achieved by the addition of other rare earths such as dysprosium and lanthanides.

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