Operating Temperatures

What are the maximum recommended operating temperatures for different magnet materials?

What are the maximum recommended operating temperatures for different magnet materials?

The maximum temperature at which a magnet remains effective depends strongly on the permeance coefficient, or "Pc", of the material. The Pc is a function of the magnetic circuit in which the magnet operates. The higher the Pc (the more "closed" the circuit), the higher the temperature at which the magnet can operate without being severely demagnetized. Approximate maximum operating temperatures for the various classes of magnet materials are shown here. At temperatures close to those listed below, special care may be needed to ensure the magnet is not demagnetized.

Material Approximate max.
operating temperatures
°C °F
NdFeB 140 284
SmCo 300 572
Alnico 540 1,004
Ceramic 300 572
Flexible 100 212