Scale-up of nanoparticle permanent magnet powder

Hysteresis loops of Sm2Fe17N3 powders prepared at scale using bottom-up and top-down approaches. Note: Powders aligned in field and fixed in wax.
Hysteresis loops of Sm2Fe17N3 powders prepared at scale using bottom-up and top-down approaches. Note: Powders aligned in field and fixed in wax.

CMI researchers from Ames National Laboratory conducted the activity for this highlight

Innovation 
Two different approaches – bottom-up and top-down – were investigated to determine the optimal method for producing the SmFeN powders at scale.

Achievement
By optimizing the top-down procedure, scaled up Sm2Fe17N3 powder production to 12g, achieving a remarkably y high Ms = 159 emu/g and Mr = 140 emu/g, with BHmax = 22.4 MGOe.

Significance and Impact

  • Criticality and cost: material is mostly Fe (~74% wt.%), containing non-critical rare earth Sm as well as earth-abundant N.
  • Next step is to form fully dense Sm2Fe17N3-based materials, comprising single grains and particles that, are expected to rival Neo magnets in performance.

Hub Target Addressed 
Accelerating discovery and deployment of new permanent magnets.