Like all magnets, temperate affects their behaviour, but unlike rare-earth magnets, when ferrite magnets get hotter their resistance to demagnetisation increases because their intrinsic coercivity improves. This unique characteristic makes them extremely popular for applications that require high operating temperatures such as electric motors and generators, they are also widely used in loudspeaker systems. The intrinsic coercivity of a ferrite magnet increases by approximately 0.4% for each degree Celsius increase (from ambient). On the downside, their output does reduce at the rate of approximately 0.2% for each degree Celsius increase. Both of these effects are reversible as the operating temperature returns to ambient, however, grades with low operating temperatures may suffer permanent demagnetisation at high temperatures.
Did you know? As ferrite magnets get hotter their resistance to demagnetisation actually increases!
This means that Ferrite magnets can be used up to about 180℃ in some cases however, they are less effective in colder temperatures, particularly below 0℃. Typically they will display a reduced pull force, the extent of which depends on the size and shape of the magnet and the environment it is applied in. With careful design, a ferrite magnet can continue to be effective in temperatures as low as -40℃.
Different shapes of magnets will react in different ways, please see the table below for the maximum operating temperature of each grade of ferrite magnet available. At first4magnets.com we supply ferrite magnets in Y10, Y30 and Y30BH grades.
|MAGNET TYPE SUFFIX||Max. Working Temperature(based on High working point)|
|Y10||180 ºC = 356 ºF|
|Y30||180ºC = 356 ºF|
|Y30BH||180 ºC = 356 ºF|
For high temperature applications, samarium cobalt and high temperature neodymium magnets should be considered.
Further Information Regarding Ferrite Magnets
How to buy Ferrite Magnets