Factors Affecting Performance and Lifetime of Magnets

Published: 2023-02-27 11:14:47 • Daniel Gårdefelt

Electric motors, medical equipment and many other industries depend on magnets. The cost-effectiveness of the product in which a magnet is used is greatly affected by its lifespan. In this article we will go through how to increase the life of magnets and the factors that affect it.

Temperature
The life of a magnet is significantly affected by the temperature at which it is used. A magnet loses power as its temperature rises, and this can also cause the magnet to demagnetize. Selecting a magnet with the correct temperature rating for the intended application is critical. You can read more about the magnetic material and its properties such as maximum temperatures under the Magnet facts tab.

Humidity
Moisture exposure can cause the magnet to corrode, which can ultimately cause it to break. Magnet life can be increased by using proper coating and packaging to prevent moisture from accumulating.

Magnetic field strength
The lifetime of the magnet can be affected by the strength of the magnetic field. The magnet can become demagnetized if it is exposed to too strong a magnetic field. Choosing a magnet with the right magnetic field strength for the intended application is therefore crucial.

Physical damage
Physical damage to the magnet, such as chipping or cracking, is possible. Mishandling during installation, transport or use may be the reason for this. Magnets must be handled with care and kept adequately protected during storage and transportation.

Corrosive environments
Magnets can corrode in certain environments, such as salt water or acid. To avoid corrosion, it is critical to select a magnet with the correct coating or protection for the intended use.

Aging
Magnets can age over time, which can result in a decrease in magnetic strength. High temperatures and magnetic fields can accelerate this aging process. To ensure that the magnet is still working correctly, it is important to regularly check its strength. Note that different magnet materials lose strength at different rates. For example, an alnico magnet can lose its magnetization significantly faster than a near-permanent magnet material such as neodymium (this provided the magnet is not exposed to more than its specified maximum temperature). There are demagnetization curves for each material where you can compare its sensitivity to other magnetic fields and loss in magnetic fields.

Magnets must be properly maintained if you want them to last longer. This includes:

Proper storage: Weaker magnets must be kept away from the magnetic field of stronger magnets. A Neodymium magnet can thus demagnetize a ferrite magnet if they are in contact for too long. A dry environment (depending on the magnetic material and surface treatment) is also important.

Correct handling: Magnets break easily. If you drop them on the ground or if you have two strong magnets that hit each other hard, there is a risk that these will break.

Regular maintenance: Regular maintenance, such as cleaning and inspection, can help detect potential problems before they occur.

Correct choice: It is important to choose the right magnet for the intended application, e.g. the temperature rating, material grade and coating to name a few.

In summary, several variables, such as temperature, humidity, magnetic field strength, physical damage, corrosive environments, and aging, affect the lifespan of magnets. Maintaining magnets properly can help them last longer and ensure they function properly, which will ultimately increase the cost effectiveness of the product in which they are used.