Toward The Reduction Of Heavy Rare Earth Elements In High Performance NdFeB Permanent Magnets By The Refinement Of The Strip Cast Flakes Microstructure

Authors:

Sorana Luca (Univ. Grenoble Alpes, CEA, Liten, France),
Christoph Brombacher (Vacuumschmelze, Grüner Weg 37, Germany),
Stephane Genevrier (Univ. Grenoble Alpes, CEA, Liten, France),
Jean Leforestier (Univ. Grenoble Alpes, CEA, Liten, France),
Hugo Dayde (Univ. Grenoble Alpes, CEA, Liten, France),
Olivier Tosoni (Univ. Grenoble Alpes, CEA, Liten, France),
Cyril Rado (Univ. Grenoble Alpes, CEA, Liten, France)

Abstract:

Sintered NdFeB permanent magnets (PM) are essential components of electrical machines that require a high energy product|volume ratio for weight reduction and better reliability. However, to compensate the decrease in magnets coercivity with temperature, substitution of Nd by Heavy Rare Earths (HRE) is widely used at industrial scale. This approach seriously increases the dependence on these critical raw materials in EU magnet industry.This work focuses on the reduction of HRE elements in the high performance NdFeB PM, by the refinement of the microstructure of the alloys. The proposed optimization of the NdFeB alloys can boost development of fine-grained NdFeB PM’s allowing a significant HRE reduction. The influence of the process parameters as well as of the alloys composition on the coercivity increase will be emphasized. Coercivity increase of 110 kA|m at 150°C have been demonstrated for magnets based on alloys with optimized microstructure and composition.

DOI:

https://doi.org/10.59499/WP225372052