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SmCo Products Overview

Click on your desired product type for product specifications.

Samarium Cobalt (or SmCo) magnets are strong permanent magnets made of an alloy of samarium and cobalt. They are known for their high magnetic strength, exceptional temperature resistance, and reliable performance without oxidation protection. As a result, they are more suitable for certain applications than Neodymium magnets.

Machining & Magnetization

Samarium Cobalt magnets offer strong resistance to demagnetization. All Samarium Cobalt magnets cannot be formed with conventional drilling, turning or milling processes, and must be ground before they are magnetized. Additionally, large or complex assemblies are usually magnetized prior to assembly. Standard tolerances for Samarium Cobalt magnets are +/-.005 for ground dimensions.

1:5 alloy material

1:5 offers 16 MGOe (energy product) to 22 MGOe and is made up of approximately 50% samarium and 50% cobalt. The 1:5 series has a maximum recommended operating temperature of 250°C. SmCo 1:5 magnets require lower field strengths than 2:17 materials to magnetize. In some instances, 1:5  material may be magnetized with multiple poles, provided that a magnetizing fixture is available.

2:17 alloy material

2:17 offers 24 MGOe to 32 MGOe and is composed of about 25% samarium, 5% copper, 18% iron, 2% hafnium or zirconium, with the remainder being cobalt. The 2:17 series has a maximum operating temperature of 350°C. Special grades of 2:17 are available which can operate to even higher temperatures. SmCo 2:17 requires a higher magnetizing field than alloy 1:5 does, and multiple pole magnetization is sometimes possible, provided that a magnetizing fixture is available.

Demagnetization Curves

A second quadrant demagnetization curve provides information about the magnetic characteristics of a magnet, including the magnetic field strength and how resistant it is to demagnetize. How it is used in a magnetic circuit will affect its performance. When a permanent magnet is fully magnetized, its magnetic domains are aligned. Certain conditions such as temperature and reverse magnetic fields can cause some of the domains to lose this alignment and reverse, triggering the magnet to lose some or all of its magnetic field. 

View our SmCo demagnetization curves here.

Samarium Cobalt Magnet Features

Samarium Cobalt (SmCo) disc magnets are powerful magnets rare earth magnets composed of samarium and cobalt. They are commonly used in high performance motors, magnetic couplings and magnetic separators. These are brittle magnets and are prone to cracking and chipping. Samarium magnets can be used for high temperature applications where neodymium will not work.

Features include:

  • Samarium cobalt magnets are hard and brittle and may chip or break if dropped.
  • They have high magnetic properties
  • Samarium cobalt magnets offer good thermal stability
  • Samarium cobalt magnets are resistant to corrosion
  • Samarium cobalt magnets resistant to demagnetization

Temperature Considerations

A Samarium Cobalt magnet can withstand higher temperatures than a Neodymium magnet. The maximum operating temperatures for Samarium Cobalt magnets are between 250 and 550 °C; Curie temperatures range from 700 to 800 °C. Additionally, a Samarium Cobalt magnet is less subject to corrosion than a Neodymium magnet, and usually does not require coating or plating.

Gluing Magnets

Several factors must be considered to assure the effective performance of the magnet, the adhesive and the resulting bond. These include the chemical and physical properties of the magnets and the surfaces to which they are affixed. Detailed coverage of all these factors, along with some adhesives to try, is covered in our white paper Gluing Magnets.