What is rare earth permanent magnetic materials?

Time: 2009-01-19
Summary: An introduction of Rare Earth Magnets - NdFeB & SmCo
The rare earth permanent magnet material is an alloy composed of a rare earth metal mixed with samarium and neodymium and a transition metal (such as cobalt, iron, etc.), which is pressed and sintered by a permanent powder metallurgy method, and is obtained by magnetic field magnetization.

Rare earth permanent magnet consists of Samarium Cobant (SmCo) permanent magnets and neodymium iron boron (NdFeB) permanent magnets. The magnetic energy product of the SmCo magnet is between 15 and 30 MGOe, and the magnetic energy product of the NdFeB magnet is between 27 and 50 MGOe. NdFeB is called "permanent magnet king" and is the strongest magnetic permanent magnet material. Samarium-cobalt permanent magnets, despite their excellent magnetic properties, contain rare earth metal samarium with rare reserves and scarce, expensive strategic metal cobalt, so its development has been greatly limited. The development of rare earth permanent magnet industry in China began in the late 1960s. The leading product at that time was samarium-cobalt permanent magnet. At present, the world sales volume of samarium-cobalt permanent magnet is 630 tons, and that of China is 90.5 tons (including SmCo magnetic powder). Military technology.

With the development of computers, communications and other industries, rare earth permanent magnets, especially the Nd-FeB permanent magnet industry, have developed rapidly.

Rare earth permanent magnet material is a kind of permanent magnet material with the highest comprehensive performance. It is more than 100 times higher than the magnetic properties of magnetic steel used in the 1990s. It is much superior to ferrite and AlNiCo. The magnetic properties of expensive platinum-cobalt alloys are also doubled. Due to the use of rare earth permanent magnet materials, it not only promotes the development of miniaturized devices, improves the performance of products, but also promotes the production of certain special devices. Therefore, once rare earth permanent magnet materials appear, they immediately attract great attention from the whole country. The development is extremely rapid. The performance of various rare earth permanent magnet materials developed and produced in China has reached or reached the international advanced level.

Nowadays, rare earth permanent magnet materials have become important materials in electronic technology communication, used in satellite waves, radars, traveling wave tubes, circulators, and micro-motors, micro-recorders, aviation instruments, electronic watches, seismographs and other electronic devices. On the instrument. 

At present, the application of rare earth permanent magnets penetrates into automobiles, household appliances, electronic instruments, magnetic resonance imagers, audio equipment, micro-motors, mobile phones and the like. In the medical field, the use of rare earth permanent magnet materials for "magnetic acupoint therapy" has greatly improved the efficacy, thus promoting the rapid promotion of "magnetic acupoint therapy". In various fields of application of rare earths, rare earth permanent magnet materials are the fastest growing one. It not only brings great impetus to the development of the rare earth industry, but also has a profound impact on many related industries.

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