New CMI capability: rare earth magnet powder synthesis in high magnetic fields

The 9 Tesla superconducting magnet accommodates the specially designed HDDR reactor.
The 9 Tesla superconducting magnet (above) accommodates the specially designed HDDR reactor (below).

 

Specially designed HDDR reactor
Specially designed HDDR reactor

This CMI research was conducted by researchers at Ames Laboratory and Oak Ridge National Laboratory. 

Achievement
Designed and demonstrated a new reactor for producing rare earth magnet materials in high magnetic fields via hydrogenation-disproportionation-desorption-recombination (HDDR) chemistry.

Significance and impact
A new capability within CMI, enabling production of magnet powders and study of magnetic field on the associated chemical reactions and the resulting microstructure and magnetic properties.

Details and Next steps

  • HDDR is a commercial process for making Nd2Fe14B-based powders by reacting with hydrogen at high temperature then reforming. Application of a field during this process provides unique control.
  • Development of this capability enables the CMI to study the role of magnetic fields in the HDDR process and optimize magnet powders in Year 8 and beyond.
     
Microstructure after processing a commercial Nd2Fe14B magnet
Microstructure after processing a commercial Nd2Fe14B magnet