Strong Magnets without Rare Earth Elements

Science News has interesting article on making magnets for use in high tech motors and speakers at http://www.sciencenews.org/view/feature/id/333202/title/Sparing_the_rare_earths_  I thought this was interesting because it shows how something old and pretty simple, making magnets, is still but interesting and economically very important.  The high tech magnets in advanced electric motors, such as those needed for hybrid cars, are made with rare earth elements such as neodymium, samarium, and dysprosium.  Magnets using these elements have the needed combination of high magnetic fields, arising from lots of unpaired electron spins, and stability.  Iron based magnets usually lack one or both of these properties.  The article describes efforts to find new alloys which work without the rare earths.  (By the way, the article contains one of my most hated mistakes:  electrons DO NOT literally spin!  We'll talk about this in class soon.)

Posted by Michael Fuson