Record 18 kOe coercivity for hot-rolled Nd-Fe-B magnets

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

Innovation
The CMI hot-rolling process has enabled high coercivity Nd-Fe-B magnets comparable without Dy. The technique offers a means for continuous and simplified magnet production process, compared to the traditional press/sinter. 

Achievement

  • Nd-Fe-B magnet produced by hot-rolling has 18 kOe coercivity without Dy.
  • Commercial magnets require 2-4 wt.% Dy for the same 18 kOe coercivity.
  • The Hot-rolling technology is a 2023 R&D-100 award winner.

Significance and Impact
Reduces U.S. need for the scarce and critical Dy in Nd-Fe-B and related magnets employed in clean energy applications such as EV traction motors and wind turbine generators.

Hub Target Addressed
Substitutes for critical-element-containing magnets.

Hysteresis loops of ‘hot-rolled’ NdFeB magnets with various grain boundary modifiers. 
Hysteresis loops of ‘hot-rolled’ NdFeB magnets with various grain boundary modifiers.