Long term stability of several common magnets at 100 ℃

What is the long-term stability of magnets at 100 degrees Celsius?Just looking at the background statistics found that some users are looking for this answer, so this article will start from the thermal stability of the magnet material, to introduce you to the stability of several common magnets at 100 degrees Celsius.

Rare earth NdFeb magnet (NdFeb)

NdFeb magnets are widely used for their excellent magnetic properties and high magnetic energy product, but their thermal stability is more general standard NdFeb magnets (such as N35, N42) have an upper limit of operating temperature of 80 ℃, and irreversible demagnetization may occur at 100 ℃ for long-term use. High temperature NdFeB magnets (e.g. H, SH, UH, EH grade) are designed for high temperature environments. H grade NdFeB has stable performance for long term use in 120℃, and EH grade can reach over 200℃. In 100℃ environment, grade H or higher grade NdFeB magnets should be selected to ensure the long-term stability of magnetic properties.  

Samarium Cobalt Magnets (SmCo)

Samarium Cobalt magnets are one of the few magnets that can maintain excellent performance in high temperature environment. They are favored for their strong oxidation resistance and stable magnetic properties, and can work for a long time at 300℃, and there is almost no change in magnetic properties at 100℃. 

Ferrite Magnets

Ferrite magnets are known for their low cost and excellent corrosion resistance, and also have good stability in high temperature environments. Its operating temperature range is from -40°C to 250°C, and its performance is stable and does not demagnetize in 100°C environments, but due to its low magnetic energy product (usually 1/10 of NdFeB), it is not suitable for applications that require a high level of magnetic force. 

High Quality Thin Rectangular Ferrite Magnet Y33 40x20x1mm

Aluminum-nickel-cobalt magnets (AlNiCo)

Much more resistant to temperatures up to 500 degrees Celsius, with no problems at all at 100 degrees Celsius. Their only weakness is that they are less resistant to demagnetization and are susceptible to interference from external magnetic fields.

Rubber Magnets

Rubber magnets are made of ferrite powder compounded with rubber material, with flexible bending characteristics, but limited thermal stability, this magnet will gradually lose flexibility and adhesion due to the aging of the rubber material in 100 degrees Celsius environment. 

The above is about the long-term stability of several common magnets at 100 ℃ introduction, in the long-term application scenarios at 100 ℃, the choice of suitable magnet materials need to be considered comprehensively magnetic properties, cost, thermal stability and demagnetization resistance, for high-performance demand scenarios, recommended high-temperature neodymium-iron-boron or samarium cobalt magnets. Ferrite magnets are ideal when budget is sensitive but high temperature resistance is required. In special applications (e.g., where high-temperature thermal stability is required), Alnico magnets excel.

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