Scientists at the Ames National Laboratory have synthesized a cerium alloy that could replace dysprosium as a rare-earth magnet. Finding a replacement for dysprosium is critical as the current demand is outpacing mining and recycling sources. Dysprosium is widely used in auto engines and wind turbines, but it is one of the rarest and costliest rare-earth elements. Cerium, on the other hand, is the most abundant rare-earth material.
The alloy was initially a mix of neodymium, iron, and boron doped with cerium. However, this alloy had a low Curie temperature (the temperature above which an alloy loses its permanent magnetic properties), a common trait in cerium-based magnets.
Researchers discovered that co-doping the alloy with cobalt solved this problem. It also gave the magnet a higher intrinsic coercivity (the ability of a magnet to resist demagnetization) than dysprosium-based magnets. The new alloy is also 20 to 40% less expensive than other rare-earth magnets while performing better than any other magnetic material at temperatures above 150°C.