Bypassing electrolysis: one-step calciothermic route from Nd2O3 to Nd2Fe14B

CMI researchers at Ames National Laboratory conducted the activity for highlight

Innovation

Direct conversion of neodymium oxide into high-purity Nd₂Fe₁₄B powders with low oxygen content, by calciothermic reduction-diffusion process (Ca-RD).

Achievement

By reducing oxidation via larger Fe particles and modified washing, we produced NdFeB powders suitable for sintering. The sintered magnet directly produced from this material has an energy product of 16 MGOe with Br = 12 kG and density 6.9 g/cc (see figure).

Significance and Impact

One-step calciothermic procedure circumvents the neodymium metallization process through direct production of Nd₂Fe₁₄B permanent magnets from Nd₂O₃ and Fe, paving a way for domestic permanent magnet production. Our innovation brings us one step closer to producing industry standard NdFeB powders by direct metallization.

Hub Target Addressed

Energy efficient rare earth metals production.

line graph and image of magnet — Room temperature B-H curve for magnet made from the NdFeB powder prepared by Ca-RD route. The magnet is shown in the inset, sticking to the metal spatula.