The effect of Mo addition on phase composition and nanostructure of nanocrystalline Zr16Co84-xMox (x = 0-2.0) melt spun at 55 m/s has been investigated. All the ribbons consist mainly of a hard magnetic Zr2Co11 phase with rhombohedral crystal structure but also contain minor amounts of soft-magnetic phases. The increase in cell volume on alloying suggests that Mo mainly enters the rhombohedral Zr 2Co11 structure and occupies the Co site. Mo addition promotes the formation of the hard magnetic phase and increases its volume fraction. The mean grain size of the hard magnetic phase remains almost unchanged with the increase of Mo content. But the average grain size of the soft magnetic phase decreases from about 200 nm to 50 nm. This promotes the exchange coupling of the hard and soft magnetic phases and thus leads to a significant increase in coercivity and isotropic energy product, from 0.6 kOe and 0.5 MGOe for x = 0 to 2.9 kOe and 4.2 MGOe for x = 1.5.
ASJC Scopus subject areas
- Physics and Astronomy(all)