As the second generation of Rare Earth permanent magnet, SmCo not only has high energy ranging from 14MGOe to 28MGOe and reliable coercive force,but also exhibits the best temperature characteristics in Rare Earth material family Compared with NdFeB, SmCo are suitable for working higher temperature.SmCo includes rare earth Sm1Co5 and Sm2Co17 and are referred to as 1:5 and 2:17 materials

Nd-Fe-B magnets and Sm-Co magnets are the major Rare-Earth magnetic materials of Magnet City.

Although these two magnets can be substituted by each other where operating temperature is less than 80°C, there still exits some feature differences. The price of Nd-Fe-B magnets is relatively lower. The (BH) max of Nd-Fe-B magnets can reach up to 48MGOe, which is higher than that of SmCo magnets. However, SmCo magnets have special advantages also. Besides its better corrosion & oxidation resistance, SmCo magnets have better temperature stability. SmCo magnets can be operated at higher temperature up to 300°C, while Nd-Fe-B magnets can not stand temperature over 200°C.

Attributes of Samarium Cobalt

• High resistance to demagnetization

• High energy (magnetic strength is strong for its size)

• Good temperature stability

• Expensive material (cobalt is market price sensitive)

Temperature Effects

SmCo magnets can operate at temperatures up to 350C , depending upon the grade and permeance coefficient. Sm₂Co₁₇ materials exhibit superior temperature characteristics as compared to the Sm₁Co₅ types.

Common Applications for Samarium Cobalt Magnets

Holding systems requiring very high holding forces, high field yoke magnets, high performance stepper, DC, servo, linear, and voice coil motors, magnetic bearings, magnetic couplings, loudspeakers, Halbach arrays, headphones, microphones, magnetic separation, instrumentation, switches, relays, magnetic resonance, sputtering, vacuum deposition, charged particle beam guidance, particle Accelerators, Undulators, Wigglers, and others.

Comparison of SmCo and NdFeB Magnets