The Magnetic family
Many people are familiar with the use of magnets for therapy, but some are quite surprised by the number of types of magnet available. I am referring not to the types and styles of magnetic bracelet used in therapy such a titanium magnetic bracelets, magnetic bracelets of silicone and the very popular hematite bracelets. I mean rather the fundamental types.
Broadly speaking there are three types of permanent magnet. There are the common and inexpensive ferrite magnets, the expensive but very powerful rare earth magnets and finally the rather exotic alnico magnets, which derive their name from the elements aluminium, nickel and cobalt.
All permanent magnets are built around iron, with the various added ingredients being used to vary the magnetic and other properties of the magnets. In some cases the elements are added to iron to give these magnets extra strength. However they can add other characteristics such as durability, reduction of oxidization etc.
Alnico magnets for example are magnetically stronger than ferrites but cheaper than rare earths, giving them a good price performance ratio. For this reason, in addition to their use in magnetic therapy, they are also in fact are widely used in motors and electro-acoustic equipment such as microphones, loudspeakers and electric guitar pickups. Their one drawback however is that they tend to lose their magnetism over time unless they are either subject to an electromagnetic field or attached to an iron shield (sometimes called a “keeper”) to protect them from this process of magnetic degradation.
Ferrites, the mainstay of the magnetic therapy industry, are also sometimes called ceramic magnets. They produced by a process known as sintering which involves heating their constituents in powdered form and moulding them under high pressure. In addition to iron, their constituents may include barium, strontium or even a plastic like substance to produce what are sometimes called “rubber magnets.”
Finally the rare earth magnets have their properties enhanced by neodymium and boron or samarium and cobalt. Both these types of magnet are expensive.
Whichever process is used, the resulting magnets can be placed in magnetic therapy bracelets and other magnet therapy products where they can be used to provide a whole range of health benefits to those who wear and use them.