Are Rare Earth Magnets In My Speaker?

Rare Magnets, contrary to what the term might suggest, are as common as tin and iron. However, it is true that the are manufactured with alloys made of rare earth materials. Such elements are spread below the earth's surface, making them usable but not easily exploitable. As discovered, 17 ferromagnetic rare earth elements are different from transition elements, which may not have magnetic properties. Such elements are also 3 times more effective compared to equivalent compounds such as ceramic (ferrite) or alnico.


NIB Magnets

Neodymium magnets came out in the early 1880s under efforts from General Motors and a Chinese academic body. Produced using a rare earth element (Neodymium) with boron and iron (transitional metals), the invention came to be known as NIB (Neon-Iron-Boron) magnets. One uses certain compounds for coating the magnet so that it stays protected from oxidation and subsequent decay Common elements used include Parylene, also known as epoxy resin, and nickel, tin, gold and zinc. The down side is that the magnets can fail to exhibit properties at moderate temperatures such as 210 degree Fahrenheit (for a low Curie temperature resistance).


At the end of the last millennium, NIB magnets have became easily procurable for a drop in prices, and now come in a variety of shapes and strengths. Often used by businesses and individuals, one can find them in various everyday items such as audio systems, turbine generators, flashlights and a number of other products . Used in toys, the permanent “rare magnet” has proven not as effective as samarium-cobalt magnet.

The Magnet of the  last Century


With a high Curie temperature resistance (500 degrees Fahrenheit), this type of magnet uses samarium, iron and cobalt. Invented under US Air Force more than 80 years after the invention of NIB magnets, these showed greater resistance to oxidation as well.  Although its powerful properties could lead one to foresee industrial benefits, they can be brittle and more expensive than NIB magnets.


Properties of Rare Earth Magnets

Magnets are graded on three accounts – which include resistance to high temperatures, strength of field and its ability to resist a countering magnetic field. The two magnets discussed above have commendable properties of magnetism, but could be losing strength and moderately high temperatures required for production and molding in some fields. However, they can be perfect for use in a large range of manufacturing and mechanical ventures. Owing to strong magnetic fields, neither neodymium nor other varieties should be placed near computers, as they could disrupt memories. The magnets should also be maneuvered carefully to avoid injuries.

Rare earth magnets have properties that could be perfect for use at home, office or a factory. Both types are applicable in different spheres of science and creation, and can be used economically for high performance.