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Ceramic Vs. Earth Magnet Heat

There are several different types of manufactured magnets, and all of them have different qualities and uses. One of these qualities is how well the magnet withstands heat, as heat alters magnetization. Two of the different types of magnets are rare earth magnets and ceramic magnets, both of which tolerate different levels of heat.

Magnetic Materials
- There are several different types of permanent magnets, which are distinguished from one another based upon their materials. Rare earth magnets are made from a compound of either neodymium, iron and boron or samarium and cobalt. They are named "rare earth" due to the fact that they contain metals from the "rare earth" series on the periodic table of the elements. Ceramic magnets are made from a combination of iron oxide and strontium carbonate. These are also known as ferrite magnets.
Heat
- Magnetic materials are able to create magnetic fields because of their properties on an atomic level. An element that is able to have magnetic properties has electrons that are configured so that the atom has a magnetic field and a polarity. The magnetic field of an individual atom is extremely weak. However, if many atoms all have the same polarity in their magnetic fields, their collective magnetic field is much stronger. However, heating a magnet will disrupt the orderly arrangement of these fields, destroying the magnet.
Ceramic Magnets
- Ceramic magnets are fairly strong and very common. However, the strength of a ceramic magnet varies greatly depending upon its temperature. In general, ceramic magnets retain only about 45 percent of their magnetic strength at 350 degrees Fahrenheit. The magnet will go back to its normal strength once returned to room temperatures unless it reaches over 840 degrees Fahrenheit, at which point the magnet becomes completely demagnetized. It can be re-magnetized if it does not reach temperatures above 1,800 degrees Fahrenheit. The precise temperatures at which ceramic magnets lose their magnetic properties depend upon the exact composition of the magnet as well as the shape. Thicker magnets are more resilient than thin magnets.
Rare Earth Magnets
- Rare earth magnets are much stronger than ceramic magnets and are noted for being the strongest type of permanent magnet. Typical rare earth magnets begin losing their strength at about 176 degrees Fahrenheit and completely lose their magnetic properties at 590 degrees Fahrenheit. However, there are many types of rare earth magnet, all with different properties. Samarium and cobalt magnets are typically more resistant to heat than ceramic magnets, and neodymium, iron and boron magnets are typically less resistant.

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