US firm Niron Magnetics says it has managed to make good quality magnets without rare earths. Instead, they use iron and nitrogen to make iron nitride magnets. This relies on getting the iron nitride to take on a specific crystalline structure, which generates magnetic fields. Chief executive Jonathan Rowntree declines to explain his company's production techniques in detail, but he says Niron has already produced working magnets. The first of these will be used in speakers.
Magnetic field strength is measured in terms of teslas, and Niron's magnets are currently at one tesla. Mr Rowntree says it should be possible to make significantly more powerful magnets, up to 2.4 teslas, with iron nitride.
Niron's targeting of the audio speakers market is interesting, says Nicola Morley at the University of Sheffield. "It means they think they can produce them cheaply - that market has other cheap permanent magnets in it," she explains. Within the last decade, the development of magnet technology has really begun to accelerate, adds Prof Morley.
Meanwhile, US firm Noveon Magnetics says it has developed its own method for magnet recycling. When asked about the process, and the grades of magnets produced, chief commercial officer Peter Afiuny declined to go into details, except to say that a small amount of alloy is mixed with recovered material to achieve the desired result. The whole process is about 40% more efficient than traditional virgin magnet production.
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