SmFeN as a cost-effective high-performance magnet

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Effect of d- and p-block element substitutions on the thermal stability of Sm2Fe17N3

CMI researchers at Ames Laboratory conducted the research for this highlight


  • Demonstrated up to 80°C improvement of the thermal stability of d- and p-block element substituted nitrides Sm2Fe17-xTxN3 (T = C, Si, Al, Zn, Cu, Ni, Co, Mn, Cr, Ti, Mo, Zr; x = 0.85)
  • For the Ti- and Cr-doped materials the energy product improves by 10-20% compared to the parent Sm2Fe17N3 compound

Significance and impact
Improved thermal stability against thermal decomposition of Sm2Fe17N3 paves the way to sintered, nearly fully dense Sm2Fe17N3–based permanent magnets – strong competitors of Nd-based magnets

Details and next steps

  • Explore co-doping with La and/or Ce to further improve thermal stability and magnetic properties of the transition metal substituted materials
  • Scale up to 2-5 g quantities
  • Demonstrate (BH)max of at least 10 MGOe for 400°C annealed materials