Q: What temperature would the magnet start to permanently lose strength?
The majority of the Neodymium magnets that Frenergy supplies are rated to tolerate temperatures up to 80℃. Above this temperature, the heat will start to impact the arrangement of the magnetic material between the poles and the magnetic field will begin to weaken. The magnet will remain in that state permanently. Neodymium ferromagnetic material has a Curie temperature of around 350℃. This is the point for Neodymium magnets where all magnetic properties are lost permanently. Other magnetic materials have different Curie temperatures. Neodymium magnets can recover if the exposure to the maximum operating temperature of 80℃ is short, but extended exposure to heat will cause irreversible partial damage or even permanent and irreversible total demagnetisation of the magnet.
Frenegy supplies High-Temperature Neodymium disc magnets to suit applications where temperatures up to 150℃ occur. In addition to the N Grade prefix which indicates the Neodymium value and strength of the magnet, temperature resistant magnets have a suffix of either S or SH. For instance, an N45SH grade Neodymium magnet can operate in temperatures up to 150℃. You can use the product filter on the Frenergy website to search for temperature resistant grades, so finding the right magnet is simple. If your application requires heat resistant disc magnets look for the S or SH suffix! Visit the Samarium Cobalt category on the Frenergy website to see more high operating temperature magnets.