High coercivity rare-earth-free Fe5C2 nanorods

graph: M-H loop at 300 K with (BH)max calculation using theoretical density of Fe5C2 (7.62 g/cm3)
Figure: (a) M-H loop at 300 K with (BH)max calculation using theoretical density of Fe5C2 (7.62 g/cm3)

CMI researchers at Ames National Laboratory conducted the activity for this highlight. 

Innovation  
A record high coercivity of 2.1 kOe is achieved in a rare-earth-free Fe-rich compound, Fe5C2.

Achievement

  • Successful synthesis of Fe5C2 nanorods with diameters of approximately 20–30 nm and aspect ratios ranging from 1 to 5. 
  • The nanocrystals exhibit a coercivity of 2.1 kOe and a maximum energy product of 7.9 MGOe.

Significance and Impact  
The significant coercivity, sufficient magnetization, high Curie temperature, and high thermal stability make Fe5C2 a promising candidate for a permanent magnet.

Hub goal addressed   
Accelerated magnet discovery and maturation.

TEM image at 100 nm scale.
Figure (b) TEM image at 100 nm scale.