What is Samarium Cobalt Magnet?

smco-magnet-introductionSamarium cobalt magnet, is a type of rare earth magnet, is a strong permanent magnet made of an alloy of samarium and cobalt. Samarium cobalt magnet was developed in the early of 1970s, their magnetic strength is just behind NdFeB Magnet, but they have higher working temperature and higher coercivity.
Samarium cobalt magnet is brittle, easy to crack and chip. They are also easy to be corroded, so they are also usually plated by Ni, Cu, Cr or other metal. Samarium Cobalt has 2 series, namely series Sm: Co=1:5 and series Sm: Co=2:17.
SmCo Magnets are produced by a powder metallurgy process which is very similar with Neodymium Magnets. They will be oriented their magnetic direction during the pressing process. And then make magnetism together within a sintering process.

Sm-Co materials come in energy products from 16 MGOe up to 33 MGOe. Their high resistance to demagnetizing influences and excellent thermal stability has ensured Sm-Co as the premium choice for the most demanding motor applications. In addition, the corrosion resistance is significantly higher than, for example, Nd-Fe-B. It is still recommended to coat the magnet in acidic conditions. Its corrosion resistance has also offered a high degree of comfort to those looking to use magnets in medical applications.

Typical Magnetic Properties

TYPICAL MAGNETIC PROPETIES OF SINTERED SMCO MAGNET
Grade Br Hcb Hcj (BH)max Density TW Max Series
kGs(mT) kOe(kA/m) kOe(kA/m) MGOe(kJ/M3) g/cm3
SmCo16 8.3(830) 8.0(640) 18.0(1430) 16.0(128) 8.3 250 1:5
SmCo18 8.8(880) 8.5(680) 18.0(1430) 18.0(144) 8.3 250
SmCo20 9.2(920) 8.7(700) 18.0(1430) 20.0(160) 8.3 250
SmCo22 9.4(940) 9.1(730) 18.5(1450) 22.0(176) 8.3 250
SmCo24 9.8(980) 9.4(750) 18.5(1450) 24.0(192) 8.3 250
SmCo24 9.8(980) 9.1(730) 18.5(1450) 24.0(192) 8.4 300 2:17
SmCo26 10.3(1030) 9.5(760) 18.5(1450) 26.0(208) 8.4 300
SmCo28 10.5(1050) 9.7(780) 18.5(1450) 28.0(224) 8.4 300
SmCo30 11.0(1100) 10.1(810) 18.5(1450) 30.0(240) 8.4 300
SmCo26M 10.3(1030) 9.5(760) 15.0(1100) 26.0(208) 8.4 300
SmCo28M 10.5(1050) 9.7(780) 15.0(1100) 28.0(224) 8.4 300
SmCo30M 11.0(1100) 10.1(810) 15.0(1100) 30.0(240) 8.4 300
SmCo28L 10.5(1050) 6.9(550) 8.0(700) 28.0(224) 8.4 250
SmCo30L 11.0(1100) 6.9(550) 8.0(700) 30.0(240) 8.4 250
SmCo24H 10.0(1000) 9.0(720) 25.0(2000) 24.0(192) 8.4 350
SmCo26H 10.3(1030) 9.5(760) 25.0(2000) 26.0(208) 8.4 350
SmCo28H 10.5(1050) 9.6(770) 25.0(2000) 28.0(224) 8.4 350
SmCo30H 10.8(1080) 10.1(810) 25.0(2000) 30.0(240) 8.4 350