Nanocomposite permanent magnet material, combining magnetically hard and soft phases in nanoscale, is a new permanent magnetic material. Compared with traditional permanent magnetic material, nanocomposite lowers rare earth content and cost, exhibits high coercivity of hard magnetic phase and high saturation magnetization of soft magnetics phase, upgrades in temperature stability, heat resistance and antioxidant ability. Till now, the main nanocomposite permanent magnets are Nd2Fe14B/Fe3B, Nd2Fe14B/α-Fe, Pr2Fe14B/α-Fe, Pr2Fe14C/α-Fe, Sm2Fe17Nx/α-Fe, and Sm2Fe17Cx/α-Fe. It is reported that Sumitomo Special Metals Co. Ltd(MMSC) succeeded in practical application and mass production for Nd2Fe14B/Fe3B material, other materials are still at the laboratory research stage.
After years of domestic and foreign scholars' efforts, great progress has been made in theoretical and experimental researches on nanocomposite permanent magnet material. And researches show that, although nanocomposite permanent magnet greatly increases in remanence, slightly decreases in coercivity, limits the increase of maximum energy product. Besides, bonding process mostly used in nanocomposite magnet forming, to further reduce its magnetic properties. Therefore, how to improve coercivity under the premise of ensuring high remanence has become a hotspot for research.
Nanocomposite permanent magnet material has excellent theoretical magnetic properties and broad application prospects. However, experimental and industrial magnetic properties are far from theoretical values, which limits its application and development. To achieve large-scale production of nanocomposite permanent magnet, in addition to strengthen the research on exchange coupling mechanism, reverse magnetization direction and coercive force itself, it is extremely important to study material composition, adding elements and preparation process.
It is always a goal of the people engaged, relying on the correct theoretical guidance, to seek a process route workable for different materials. It can be predicted, with the perfection of theoretical and experimental methods, nanocomposite permanent magnet material will have a broader space for development.
Rotate-release with Alignment Feature
Magnet for Hall Effect Sensor Application
Polymagnets® are multi-pole encoded magnets that contain small magnetic elements called maxels. Polymagnets® can produce superior attachment forces, safer magnets, precision alignment, shear and torque stiffness, and complex, multi-level/multi-force control on a scale that has not been achieved with traditional magnets.
Polymagnet® technology leverages the attraction and repel forces of magnetism, exploiting the idea of controlled cancelation or interaction of these forces in space. The arrangement or pattern of maxels creates a unique magnetic circuit that defines the function of the Polymagnet® device and its interaction with other magnets or ferrous metals.
Polymagnet® MagPrinter® allows encoding of polarity patterns into a magnet and can be tailord to meet your specific application requirements, allowing for:
• Magnets with unique functions
• Multiple forces per magnetic surface
• Stronger forces - especially on the magnet face
• Control the "reach" and "shape" of the magnetic field
High Temperature Superconductor(HTSC) YBCO, as the next generation of industrial permanent magnet, is up to 10 times higher than current rare earth permanent magnet in magnetic field performance. This special ceramic material reaches an operating temperature 90K at 77K liquid nitrogen, which is found to be applied in automation technology/flywheel energy storage/motor/generator/maglev/medical/ aerospace. With a demand of next stronger permanent magnet from high-end users, we will own a huge HTSC market.
SmCo magnet, a rare earth magnet, made of mixing samarium, cobalt and other metal rare earth materials in a specific ratio, melting into alloy, powdering, pressing and sintering. With the features of high magnetic energy product, extremely low temperature coefficient, highest working temperature 350 ℃ and non-limited negative temperature, when operating temperature is above 180 ℃, the maximum magnetic energy product (BHmax), coercivity, temperature stability and chemical stability will do better than NdFeB permanent magnet.
SmCo magnet has a strong anti-corrosive and anti-oxidized ability, it is widely used in aerospace, defense and military, microwave devices, communications, medical equipment, instruments, meters, all magnetic actuators, sensors, magnetic processors, motors, magnetic crane, and so on.
At present, the maximum energy product has stabilized to 32MGOe, close to the theoretical value 34MGOe(Sm2Co17).
As an important part of new materials, rare earth permanent magnet materials are widely used in energy, transportation, machinery, medical treatment, IT, home appliances, and other industries. Such as manufacturing various permanent magnetic motors, taptic engine, permanent magnet meters, electronics, nuclear magnetic resonance (NMR), audio equipment, magnetic therapy equipment, and etc. The products distribute in lot of fields of national economy.
Conventionally, alloying addition Dy and Tb elements is the most way to increase magnet coercivity. But there is a ferromagnetic coupling between Dy, Tb or other heavy rare earth elements and Fe atoms, to lower magnet remanence and maximum energy product. In addition, heavy rare earth has low reserves and high cost. To improve performance and save cost simultaneously, Dy/Tb grain boundary diffusion method has introduced in recent years. Dy/Tb diffusion along the grain boundary liquid, optimizes the microstructure of grain boundary, greatly improves coercivity with keeping the same magnet remanence, effectively reduces the use of heavy rare earth.