Alloys Found in Magnets
- Neodymium iron boron magnets are also known as rare earth magnets because they are made from elements in the rare earth series in the periodic table. These magnets are made from an alloy of these three elements, neodymium, iron and boron. Iron is a common component in magnets. These magnets are physically rather weak but have powerful magnetic fields and can resist fairly high temperatures, which is important as extreme temperature can demagnetize a magnet.
- Samarium cobalt is another type of rare earth magnet. These are alloys of samarium and cobalt; cobalt is another element commonly used in magnets due to its unbalanced electron spin. Like neodymium magnets, Samarium cobalt magnets are very powerful and can be very brittle, as well. The dust created from grinding these magnets is dangerous, as it is highly flammable and can ignite from a electrostatic spark. This type of magnet is sometimes plated with nickle, which is also easily magnetized and has the benefit of being easy to clean.
- Alnico magnets are magnets that are made of an alloy of aluminum, nickle and cobalt. These magnets are weak in comparison to rare earth magnets, are brittle, and are also easily demagnetized. However, they can withstand extremely high temperatures, retaining their magnetic properties at up to 1,000 degrees Fahrenheit. Demagnetized alnico magnets are also easily remagnetized. These magnets are also appealing in that they can be cast into many shapes, such as the U shape of a horseshoe magnet.
- Ceramic magnets, also known as ferrite magnets, are composed of strontium carbonate and iron oxide, and contain the elements strontium, carbon, oxygen and iron. These magnets are weak compared to rare earth and alnico magnets and their strength varies greatly with temperature. These magnets can be found in a few different shapes but do not have a large variety of shapes and are very brittle. The main appeal of ceramic magnets is their low cost in relation to alnico and rare earth magnets.
