Neodymium is a rare-earth element essential for producing the strongest permanent magnets, which are widespread in defense technologies, hard drives, medical imaging devices, electric vehicle motors, wind turbines and more. Despite its designation in the U.S. as a critical material, neodymium is primarily mined and refined overseas. China controls much of the supply chain, and the country recently threatened to expand restrictions on the exports of rare earth elements.
A domestic capability to produce critical materials like neodymium would address supply chain vulnerabilities in the U.S. To this end, researchers at Lawrence Livermore National Laboratory (LLNL), Case Western Reserve University (CWRU) and Ames National Laboratory developed a new process for neodymium magnet fabrication that generates high-purity material at high efficiency.
"We hope this method becomes a cornerstone for domestic production of neodymium magnets," said author and LLNL scientist Eunjeong Kim. "It can enable a truly U.S.-based 'mine-to-magnet' manufacturing chain from rare-earth mining and separation to final magnet fabrication, reducing reliance on overseas processing."
The U.S. has neodymium deposits, but refining the material has remained out of reach due to the energy-intensive process, permitting restrictions and the lack of a qualified workforce.
The new method could address all three barriers. It operates based on chloride molten salt electrolysis. In basic terms, neodymium enters the system attached to chloride ions. The electrolysis setup uses electricity to split the incoming molecules apart, pulling the neodymium to one end of the system (the cathode) and the chloride to the other (the anode).
Compared to traditional refining approaches, the process skips two major, energy-intensive steps and doesn't produce harmful gases as a byproduct. Because the anode design prevents degradation, the device can operate continuously.
"This is economically advantageous," said Kim. "Production costs can be reduced from over $14 per kilogram of neodymium in conventional methods to approximately $5 per kilogram using our method."
And neodymium is just the start. Chloride molten salt electrolysis can also be extended to other rare-earth metals critical for energy technologies.
This work represents a strong collaboration within the Critical Materials Innovation Hub. CWRU led the electrochemical design and process modeling. LLNL contributed materials characterization and anode fabrication, and Ames used the material produced to fabricate magnets that were comparable to industry standards.
Now, CWRU is working to scale up the electrolysis setup design, while LLNL tests new deposition approaches to further stabilize the anode.
"Together, this partnership showcases how national labs and academia can jointly drive innovation toward secure and sustainable materials manufacturing," said Kim.
