Scientists have created a promising new magnetic material that could lead to cheaper cars and wind turbines.
The new magnetic alloy is a viable alternative to expensive rare-earth permanent magnets, the U.S. Department of Energy and Ames Laboratory reported. The material could eliminate the need for one of the "scarcest and costliest" rare Earth elements, dysprosium, and replace it with abundant cerium.
The alloy is composed of neodymium, iron and boron "co-doped "with cerium and cobalt. Recent experiments demonstrated the cerium-containing alloy boasts intrinsic coercivity (the ability of magnetic material fight demagnetization) that is even greater than dysprosium's containing magnets of high temperatures. This material is also between 20 and 40 percent cheaper than magnets containing conventional dysprosium.
"This is quite exciting result; we found that this material works better than anything out there at temperatures above 150 [degrees Celsius]," said study leader Karl A. Gschneidner. "It's an important consideration for high-temperature applications."
Past attempts to use cerium in rare-earth magnets were unsuccessful because the element reduces the Curie temperature (the temperature at which an alloy loses its magnetic properties). This new co-doping method coupled with cobalt allowed the scientists to substitute cerium for dysprosium without reducing the magnetic properties of the material.
"Finding a comparable substitute material is key to reducing manufacturing reliance on dysprosium; the current demand for it far outpaces mining and recycling sources for it," the researchers concluded.
The paper "Cerium: An Unlikely Replacement of Dysprosium in High Performance Nd-Fe-B Permanent Magnets" was published in a recent edition of the journal Advanced Materials.