Giant magnetic anisotropy in Ce substituted SmCo5

Predicted 4f charge densities of Ce and Sm utilizing quadrupolar only (upper row panel) and both quadrupolar and octopolar (middle row panel) interactions in the crystal field model. The base CaCu5-type crystal structure (bottom row panel) to develop 2x2x1 supercell to accommodate Ce and Sm in Ce0.5Sm0.5Co5 composition.

CMI researchers at Ames Laboratory conducted the activity for this highlight

Innovation 
An ab-initio coupled crystalline electric field modeling to enhance ( > double) the magnetocrystalline anisotropy of SmCo5 via Ce substitution. 

Achievement
Developed a crystalline electric field modeling mechanism coupled with localized density functional theory calculations and predicted giant magnetic anisotropy and its origin.

Significance and impact

  • Crystalline electric field modeling coupled with localized density functional theory correctly predicts magnetocrystalline anisotropy of mixed rare earth permanent magnet materials.
  • Identified site substituted SmCo5 uplifts its permanent magnet performance.
  • Potential improvement of magnetization via small substitution of Fe.

Hub target addressed 
Win industry adoption of three technologies related to materials substitution for rare earth magnet materials. 
 

Predicted 4f charge densities of Ce and Sm utilizing quadrupolar only (upper row panel) and both quadrupolar and octopolar (middle row panel) interactions in the crystal field model. The base CaCu5-type crystal structure (bottom row panel) to develop 2x2x1 supercell to accommodate Ce and Sm in Ce0.5Sm0.5Co5 composition.
Predicted 4f charge densities of Ce and Sm utilizing quadrupolar only (upper row panel) and both quadrupolar and octopolar (middle row panel) interactions in the crystal field model. The base CaCu5-type crystal structure (bottom row panel) to develop 2x2x1 supercell to accommodate Ce and Sm in Ce0.5Sm0.5Co5 composition.