Have you ever picked up a magnet only to find it just won’t do its job? Something must have demagnetized that magnet, rendering it unusable. But what factors can cause a magnet to lose its magnetism? This is important knowledge for folks regularly working with magnets in their work or just in their hobbies.

There are a few different ways to demagnetize a magnet and we’re covering 5 of the most effective methods here:

Volume Loss

The best way to remove a magnetic field from a magnet is through the removal of mass. If the volume of the magnet is reduced, the magnetic field will also be reduced if not entirely eradicated. This can happen when a portion of the magnet is split from the main body of the magnet, however, more often than not, this happens through corrosion. Typically a loss of performance due to corrosion or the magnet breaking is obvious and observable even to the untrained eye.

High Heat

Applying heat to a magnet causes the magnet’s electrons to dance and transition into higher energy states. This, in turn, forces the electrons into different alignments. Since the electrons are no longer aligned, the magnetism of the object will decrease. The temperature at which a magnet demagnetizes is known as the Curie temperature and can be as high as 1390 degrees Fahrenheit depending on the materials the magnet is made of.

Reverse Field

The magnetic field can be removed from a magnet by applying a reversed magnetic field to the magnet. This can be accomplished by passing an alternating current through an alternating current through a component of the magnet.

Impact

Even if a piece isn’t removed from the magnet as we discussed earlier in this blog, significant force can still throw a magnet out of magnetization. Hitting a magnet with enough force to destroy its north and south pole alignment will force the magnet out of alignment. Any violent trauma can cause this to happen including drilling and hitting with a tool. If the grains inside the magnet no longer line up properly, the magnet will no longer function properly.

Time

As we saw earlier, heat can cause a magnet to lose its magnetism - This includes even mild heat. That means that after a long period of time, even room temperature heats can cause a magnet to lose its magnetism. While it will take a much, much longer time than higher temperatures, it will work eventually.
Unfortunately (or perhaps, fortunately), magnets aren’t forever. They can be demagnetized using a few simple methods. Luckily, magnet news can never be demagnetized! We’re always interested in the next discovery and finding. Stay up to date on the latest with the Apex Magnets blog or monthly newsletter, where you'll also get access to exclusive sales on your favorite Apex products!