The first commercial rare earth material, Samarium Cobalt is a rare earth magnetic material discovered in the early 1970’s. It’s manufactured by a milling, pressing, and sintering process mostly carried out in an inert atmosphere. Two distinct alloy series are available Sm1Co5 and Sm2Co17. Other characteristics of SmCo include:

•Maximum energy product of 18 to 20 MegaGauss-Oersted (MGOe), a low- temperature coefficient and high stability.

•The maximum temperature of use is 250oC depending on the specification, dimensions, and system design.

SmCo is less energetic than NdFeB, but much more energetic than AINiCo or Ferrite. The balance between performance and cost dictates whether a Sm1Co5 or Sm2Co17 will be chosen for a specific application.

ENVIRONMENTAL 

Samarium Cobalt magnets have two distinct advantages when compared to NdFeB magnets:

PERFORMANCE

• Excellent thermal performance - SmCo magnets perform well at both hot and cold extremes of temperature which NdFeB magnets cannot withstand.

• Highly corrosion resistant - The magnets do not need to be coated; they will survive most normal industrial environments without any degradation.

Like NdFeB magnets, SmCo is a sintered material and thus is mechanically brittle, chipping easily. Care should be taken to avoid contact either in the application or in the assembly of the product it is used in.

APPLICATIONS

In the 1970’s SmCo was widely used where rare earth energy products were required. After NdFeB was introduced into the market, the range of applications using SmCo was reduced. However, it’s still used in applications that require extreme temperatures and/or no risk of corrosion. Including:

• Medical implants and prostheses

• High-temperature pumps and motors

• Instrumentation where thermal stability is paramount