Abstract
The crystalline Sm-Co alloys show excellent hard magnetic properties, while the amorphous Sm-Co alloys have a poor performance. In this paper, Sm12Co76-xFe4Zr7Cu1Bx (x = 0, 2, 4, 5, 5.2) ribbons were melt-spun at 40 m/s, and the effects of B content on the phase composition, microstructure, and magnetic properties of the ribbons were studied. The results show that the main phase of all ribbons with different B content is Sm(Co, M)7. With an increase in B content, the content of amorphous and fine soft magnetic phases increases. Besides, nano-scale crystalline clusters are embedded in the amorphous matrix, forming different forms of exchange coupling microstructures between the soft and hard magnetic phases. The x = 5 ribbons have the finest grains, the most uniform grain distribution, and the strongest exchange coupling effect. Without heat treatment, their coercivity reaches 19.5 ± 0.9 kOe, and the other magnetic properties are also excellent, Mr = 24.8 ± 1.7 emu/g, M2T = 29.0 ± 1.7 emu/g, and Mr/M2T = 0.858 ± 0.015.
NSTL
Elsevier