Samarium Cobalt Magnet

Samarium Cobalt (SmCo) magnet is a strong permanent magnet made of samarium, cobalt and other minor elements. It is known for its high magnetic strength and good temperature stability. The performance of SmCo magnets is generally close to that of rare earth neodymium magnets at room temperature. In extreme temperatures, such as high temperature and ultra-low temperature environments, SmCo magnets still operate reliably while neodymium magnets generally cannot work properly. Since SmCo magnets have strong resistance to corrosion and oxidation, coating is usually not required. It should be noted that SmCo magnets are made by sintering, they are very brittle and cracks may appear inside.

Sm1Co5

SmCo5 alloy is a combination of one samarium atom for every five cobalt atoms and is the first generation of SmCo magnets. The maximum magnetic energy product (BH)max of 1:5 type SmCo is in the range of 15 MGOe to 25 MGOe, and the operating temperature is up to 250℃. SmCo5 mainly contains Sm and Co, and does not contain iron. Therefore, compared with 2:17 type SmCo magnets, 1:5 type SmCo has better corrosion resistance and demagnetization resistance.

Sm2Co17

Compared with SmCo5, 2:17 type SmCo has better magnetic properties. Its (BH)max usually varies between 24 MGOe and 32 MGOe, and the operating temperature can reach 350℃. Sm2Co17 contains few other elements, such as iron and copper. The presence of iron in Sm2Co17 means that it may corrode slightly in a high humidity environment, so Sm2Co17 magnets are often surface treated, such as Ni plating and Zn plating.

Magnetic Properties of Sintered Samarium Cobalt

category Grade Br Hcb Hcj (BH)max Working Temperature Density
T kGs kA/m kOe kA/m kOe kJ/m3 MGOe ˚C g/cm3
Sm1Co5 Sm1Co5-16 0.79-0.84 7.9-8.4 620-660 7.8-8.3 ≥1830 ≥23 118-135 15-17 ≤250 8.3
Sm1Co5-18 0.84-0.89 8.4-8.9 660-700 8.3-8.8 ≥1830 ≥23 135-151 17-19 ≤250 8.3
Sm1Co5-20 0.89-0.93 8.9-9.3 684-732 8.6-9.2 ≥1830 ≥23 150-167 19-21 ≤250 8.3
Sm1Co5-22 0.92-0.96 9.2-9.6 710-756 8.9-9.5 ≥1830 ≥23 167-183 21-23 ≤250 8.3
Sm1Co5-24 0.96-1.00 9.6-10.0 740-788 9.3-9.9 ≥1830 ≥23 183-199 23-25 ≤250 8.3
Sm2Co17 Sm2Co17-24L 0.95-1.02 9.5-10.2 541-716 6.8-9.0 636-955 8-12 175-191 22-24 ≤250 8.4
Sm2Co17-26L 1.02-1.05 10.2-10.5 541-784 6.8-9.4 636-955 8-12 191-207 24-26 ≤250 8.4
Sm2Co17-28L 1.03-1.08 10.3-10.8 541-764 6.8-9.6 636-955 8-12 207-220 26-28 ≤250 8.4
Sm2Co17-30L 1.08-1.15 10.8-11.5 541-796 6.8-10.0 636-955 8-12 220-240 28-30 ≤250 8.4
Sm2Co17-32L 1.10-1.15 11.0-11.5 541-812 6.8-10.2 636-955 8-12 230-255 29-32 ≤250 8.4
Sm2Co17-26M 1.02-1.05 10.2-10.5 676-780 8.5-9.8 955-1433 12-18 191-207 24-26 ≤300 8.4
Sm2Co17-28M 1.03-1.08 10.3-10.8 676-796 8.5-10.0 955-1433 12-18 207-220 26-28 ≤300 8.4
Sm2Co17-30M 1.08-1.1 10.8-11.0 676-835 8.5-10.5 955-1433 12-18 220-240 28-30 ≤300 8.4
Sm2Co17-32M 1.10-1.13 11.0-11.3 676-852 8.5-10.7 955-1433 12-18 230-255 29-32 ≤300 8.4
Sm2Co17-33M 1.13-1.15 11.3-11.5 820-870 10.3-10.9 955-1433 12-18 246-262 31-32 ≤300 8.4
Sm2Co17-22 0.93-0.97 9.3-9.7 676-740 8.5-9.3 ≥1433 ≥18 160-183 20-23 ≤300 8.4
Sm2Co17-24 0.95-1.02 9.5-10.2 692-764 8.7-9.6 ≥1433 ≥18 175-191 22-24 ≤300 8.4
Sm2Co17-26 1.02-1.05 10.2-10.5 748-796 9.4-10.0 ≥1433 ≥18 191-207 24-26 ≤300 8.4
Sm2Co17-28 1.03-1.08 10.3-10.8 756-812 9.5-10.2 ≥1433 ≥18 207-220 26-28 ≤300 8.4
Sm2Co17-30 1.08-1.10 10.8-11.0 788-835 9.9-10.5 ≥1433 ≥18 220-240 28-30 ≤300 8.4
Sm2Co17-32 1.10-1.13 11.0-11.3 812-860 10.2-10.8 ≥1433 ≥18 230-255 29-32 ≤300 8.4
Sm2Co17-33 1.13-1.15 11.3-11.5 820-870 10.3-10.9 ≥1433 ≥18 246-262 31-32 ≤300 8.4
Sm2Co17-24H 0.95-1.02 9.5-10.2 692-764 8.7-9.6 ≥1990 ≥25 175-191 22-24 ≤350 8.4
Sm2Co17-26H 1.02-1.05 10.2-10.5 748-796 9.4-10.0 ≥1990 ≥25 191-207 24-26 ≤350 8.4
Sm2Co17-28H 1.03-1.08 10.3-10.8 756-812 9.5-10.2 ≥1990 ≥25 207-220 26-28 ≤350 8.4
Sm2Co17-30H 1.08-1.10 10.8-11.0 788-835 9.9-10.5 ≥1990 ≥25 220-240 28-30 ≤350 8.4
Sm2Co17-32H 1.10-1.13 11.0-11.3 812-860 10.2-10.8 ≥1990 ≥25 230-255 29-32 ≤350 8.4
Sm2Co17-33H 1.13-1.15 11.3-11.5 830-880 10.4-11 ≥1990 ≥25 246-262 31-32 ≤350 8.4

Low Remanence Temperature Coefficient Samarium Cobalt Magnets

The remanence temperature coefficient of a magnet indicates how much the remanent magnetization (Br) changes with temperature. It’s typically expressed in Percent per degree Celsius (%/°C).

Normally, the remanence temperature coefficient of SmCo magnets is -0.03%/℃. We also provide products with low temperature coefficients for special use environments.

Grade Br Hcb Hcj (BH)max Working Temperature Temperature coefficient（Br） Density
T kGs kA/m kOe kA/m kOe kJ/m3 MGOe ˚C %/℃ g/cm3
Sm2Co17-16LT 0.81-0.85 8.1-8.5 605-669 7.6-8.4 ≥1592 ≥20 111-127 14-16 ≤300 -0.01 8.4
Sm2Co17-18LT 0.85-0.9 8.5-9.0 629-708 7.9-8.9 ≥1592 ≥20 127-143 16-18 ≤300 -0.01 8.4
Sm2Co17-20LT 0.9-0.94 9.0-9.4 661-732 8.3-9.2 ≥1592 ≥20 143-159 18-20 ≤300 -0.01 8.4
Sm2Co17-22LT 0.94-0.97 9.4-9.7 685-740 8.6-9.3 ≥1592 ≥20 159-175 20-22 ≤300 -0.01 8.4

Super High Temperature Resistant Samarium Cobalt Magnets

SmCo magnets are well known for their excellent thermal stability and high temperature anti-demagnetization performance, and are very suitable for use in harsh environments. The maximum operating temperature of conventional SmCo magnets is 350 degrees Celsius. By adjusting the formula and production process, we can also produce SmCo magnets with a maximum operating temperature of 500 degrees Celsius. If you need such products, please contact our sales.

Key Application of Samarium Cobalt Magnets

Samarium cobalt (SmCo) magnets are widely used in various applications due to their high magnetic strength, temperature stability, and resistance to corrosion. Here are some key applications:

1. Aerospace and Defense

Used in satellite systems, aircraft motors, and guidance systems due to their ability to perform reliably in extreme temperatures and conditions.

2. Automotive

Found in electric motors, sensors, and actuators, particularly in hybrid and electric vehicles, where high-temperature performance is crucial.

3. Medical Equipment

Utilized in MRI machines and other imaging devices, as well as in dental equipment and surgical tools due to their compact size and strong magnetic fields.

4. Industrial Applications

Employed in various types of sensors, such as position sensors, and in magnetic bearings for precision machinery.

5. Consumer Electronics

Used in high-performance headphones, speakers, and microphones, where strong magnets contribute to sound quality.

6. Robotics and Automation

Used in motors and actuators for robotics, where durability and performance are key.

7. Magnetic Couplings and Clutches

Employed in applications where a non-contact transfer of torque is required, offering advantages in terms of wear resistance and maintenance.

8. Research and Development

Used in experimental setups and various research applications due to their unique magnetic properties.