Rare Earth Magnets: What Isn’t in a Name


  What makes rare earth magnets so rare? It's really no […]

  What makes rare earth magnets so rare? It's really nothing. The history behind the discovery of rare earth elements gave rise to this name, and it is believed that two factors have contributed to this misnomer.


  When rare earth elements (REE) were discovered, they were initially considered rare because they were not located in concentrated pockets like other elements-hence the name rare earths. Fast forward a few decades and it is obvious that these elements are indeed abundant, but they are not common in concentrations that can be economically mined. In recent years, more than 124,000 tons of rare earth elements have been mined globally, with another 130 million tons of reserves.


  Another reason for using this nickname is the difficulty of separating the required elements from the mined ore. The preliminary method of separating REE from other minerals frustrated chemists. Although we have a better understanding of how to deal with REE, mining and processing of REE can be expensive and complicated.


  There are 17 rare earth elements, including 15 elements in the lanthanide series and two other elements (yttrium and scandium, because they are often found together with the lanthanide elements in nature). Even the least abundant rare earth element thulium, its content is 200 times higher than gold. In contrast, neodymium is almost as common as tin or zinc.


  Rare earth elements are found in the earth's crust and are distributed in almost every continent and 79 countries/regions. Since the 1950s, people have been actively mining rare earth elements. But with the surge in demand in the past two decades, Asia has largely dominated the mining of rare earth mines. At present, China accounts for 95% of the output of rare earth materials, of which more than 35% are magnetic materials.


  The value of rare earth magnets


  REE is valued for its strength, luminescence, and-of course, magnetism. The two most common rare earth elements in the magnetic industry are neodymium and samarium. The term rare earth magnet refers to two types of magnets: neodymium iron boron (NdFeB) and samarium cobalt (SmCo) magnets. Although, many people use neodymium and rare earth to mean the same thing. Each type of rare earth magnet has slightly different properties, making it suitable for different applications.


  In particular, rare earth magnets are touted for their unique strength. Companies seeking stronger magnetic materials have obtained patents for rare earth magnets. Samarium cobalt was first patented by the American Materials Laboratory in 1966, and again by Raytheon in 1972. Neodymium magnets were patented by General Motors in 1983, and it didn't take long for other industries to see the value of rare earth magnets. With its super strength, the application fields are endless.


  Rare earth magnets around us


  Today, almost everything we open uses rare earth magnets. Cell phones, laptops, tablets, and other electronic devices use rare earth magnets. Rare earth magnets are one of the factors that allow manufacturers to develop smaller and smaller devices.


  Electric vehicles and hybrid vehicles rely on batteries derived from rare earth compounds. From manufacturing to medical to environmental industries, rare earth magnets are also turning to them because of their size, strength, and reliability. Manufacturers use rare earth magnets for separation and lifting during the manufacturing process.


  Other common uses include:


  Audio speakers and headphones


  Computer optical drive




  Fishing reel brake


  Guitar pickup


  Hand tools


  Linear actuator


  Magnetic resonance imaging (MRI) equipment)


  Satellite system


  servo motor


  Traveling wave tube

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