Structural evolution of anisotropic SmCo6.8Hf0.2 nanocrystalline magnet prepared by hot deformation

Abstract

SmCo7-based permanent magnets with a TbCu7-type structure have excellent high-temperature performance. However, most of the previously reported SmCo7 nanocrystalline magnets were isotropic, which limited their application. So the preparation of anisotropic SmCo7 magnets with preferred texture is still a challenge. In this work, we prepared anisotropic SmCo6.8Hf0.2 nanocrystalline magnets by hot pressing and hot deformation method. EBSD results indicated that the {0001} orientation texture of the hot deformed magnet was remarkably preferred, which further improved the remanence. Subsequently, the structural evolution process was systematically characterized by TEM. It provides crucial insight for developing high-performance SmCo7-based magnets.Impact Statement: Up to now, most of the previously reported SmCo7 nanocrystalline magnets were isotropic, which limited their application. This work opens up new opportunities to create high-performance SmCo7-based nanostructured magnets.

Keywords

• Hot deformation
• anisotropic nanocrystalline magnet
• precipitated phase
• phase transition
• twins