Are Magnets Affected by Temperature?
Magnets are everywhere. They are used in cars, clasps, jewelry, electronics and security systems. They power the speakers in your headphones. They hold your refrigerator doors shut. Even the earth is a magnet. Magnets play a crucial role in our everyday life, but have you ever wondered if they are affected by temperature?
How does temperature affect magnets?
Temperature can either strengthen or weaken a magnet’s magnetic force.
Heat will reduce the magnetic force of a magnet. Heat speeds up the rate at which the particles within the magnet move. When they move faster, they move more sporadically and misalign. In order for a magnetic to be a magnetic most of the magnetic molecules must be facing the same direction, so that each end of the magnet has opposite charges. When the particles begin moving faster the polar molecules move around as well and not as many of them will end up facing the same direction. This results in a decrease in the magnetism of the magnet.
Cold has the opposite effect. Exposing a magnet to colder temperatures will increase its magnetism. The molecules within the magnet will move slower because they have less kinetic energy so there is less vibration within the magnet’s molecules. This allows for a more concentrated magnetic field that strengthens the magnet.
In addition to affecting the strength of the magnet, temperate can also affect the ease at which a magnet can be demagnetized. Like magnet strength, resistance to demagnetization generally decreases by increasing the temperature. One exception to this is ceramic magnets. It is easier to demagnetize a ceramic magnet at a lower temper.
The material the magnet is made of will also affect how it reacts to temperature. Some materials are more susceptible to the effects of temperature than others. Alnico magnets have the best strength stability, but the lowest resistance to demagnetization. Where neodymium magnets are the most resistance to demagnetization but have the biggest strength changes with temperature. Of course neodymium magnets are also the most powerful magnets in the world, so it likely won’t affect the application.
At US Magnetix, we believe that a product is only as great as the materials used to make it. Let us help you find the right magnet for your project. We offer a large selection of high-quality industrial magnets. Give us a call at 800-330-1432 or send us a message.