Abstract
Neodymium magnets possess the best integrated magnetic properties by now, which is called "the king of magnet". Its applications range from children’s toys to advanced instruments in the universe. Among these webpages, basic information, applications, processing route, manufacturing method, safety data sheet and property profile were presented. At the same time, the future development direction of the research field of neodymium magnet was discussed.
Video
Literature Review
Neodymium magnet was discovered in 1982[1] which has multiple superior properties, such as high magnetic energy product, high coercive force and high working temperature[2]. Additionally, it has the highest magnetic energy product in industrialization[3]. In consequence, neodymium magnet has a wide range of applications including large and medium-sized motors, wind power generator, information technology etc. The demand for neodymium magnet is increasing rapidly nowadays.
Table 1: Main Applications of High Performance NdFeB Magnets[2]
Sintering, bonding and hot pressing are the three common methods to manufacture neodymium magnet and sintering is the most used one[2].
Introduction
Neodymium magnet, whose full name is neodymium iron boron magnet, was discovered in 1982 and became the third generation rare earth permanent magnetic material[1].
It has similar properties as the Samarium Cobalt except that it is more easily oxidized and generally doesn’t have the same temperature resistance. Neodymium magnet possesses the best integrated magnetic properties by now. For example, it has the highest energy products. Its high energy products lend itself to compact designs that result in innovative applications and lower manufacturing costs[4].
As a result of its superior properties, it has a wide range of applications ranging from children's toys to advanced instruments in the universe.
Figure 1: Buckyballs[4]
Figure 2: Alpha Magnetic Spectrometer
Property Profile
| Price | 200-220 CNY/kg |
| Young's modulus | 152-157 GPa |
| Maximum service temperature | 80-150℃ |
| Magnetic type | Permanent manet |
| Maximum energy product | 2.86e5-3.02e5 j/m3 |
| Coercive force | 8.67e5-9.95e5 A/m |
| Remanence | 1.22-1.26 T |
Concepts and Terms
Maximum energy product: An index expressing the performance of a permanent magnet, which equals the product of maximum magnetic induction intensity(Bm) and maximum magnetic field intensity(Hm). When a magnetic circuit is designed to operate at the maximum energy product point, the magnet volume is reduced to its smallest value[5].
Coercive force: Coercive force is the value of the external magnetic field that brings to zero the magnetization or magnetic flux density of a magnetic body. The higher the coercive force, the better the magnet can preserve the magnetism[6].
Remanence: Remanence, also called residual magnetization, is the value of the flux density remaining when the external field returns from a high value of saturation to 0. The higher the remanence value, the higher the usable magnetic flux density[7].
Reference
[1]Yutaka Matsuura. Recent development of Nd2Fe2B sintered magnets and their applications[J ]. Journal of Magnetism and Magnetic Materials ,2006 ,303 :344 - 347.
[2]Wang Fang. (2018). Development of Nd-Fe-B permanent magnetic materials. Gansu Science and Technology Vertical and Transverse, v.47; No. 278 (08), 50-53
[3]Zhou Shouzeng. Ultra-strong permanent Magnet-Rare earth ferrous permanent magnet [M]. Beijing: Metallurgical Industry Press, 2004
[4]Neodymium Magnet, Super Strong Rare Earth Magnet Supplier, HSMAG. Retrieved from:http://www.neodymiummagneti.com/
[5]Neodymium Magnet, Super Strong Rare Earth Magnet Supplier, HSMAG. Retrieved from:http://www.neodymiummagneti.com/magtech/maximum-energy-product/
[6]Neodymium Magnet, Super Strong Rare Earth Magnet Supplier, HSMAG. Retrieved from:http://www.neodymiummagneti.com/magtech/coercive-force/
[7]Neodymium Magnet, Super Strong Rare Earth Magnet Supplier, HSMAG. Retrieved from:http://www.neodymiummagneti.com/magtech/remanence/