Today’s best magnets – needed for making more efficient car engines and wind turbines – rely on rare earth metals, whose supply is becoming unreliable even as demand grows. The rare earth metal neodymium is a crucial component of the strongest magnets, and other rare earths, including dysprosium and terbium, are also used. The supplies of all three of these rare earths are at risk due to increasing demand and the threat that China, which produces most of them, may restrict exports. Now researchers are working on new types of nanostructured magnets that would use smaller amounts of rare earth metals than standard magnets. GE Global Research, for one, hopes to demonstrate new magnet materials within the next two years. Steven Declos, manager of material sustainability at GE Global Research, says “A lot of the story about rare earths has focused around China and mining. We believe technology can play a role in addressing this.” Nanocomposite magnet materials, are comprised of nanoparticles of the metals that are found in today’s magnetic alloys, but offer several advantages: they promise to be stronger than other magnets of similar weight; and, they should use less rare earth metals. The concern is whether or not the new magnets will get to market before the demand for rare earth metals exceeds the supply.