Please use this identifier to cite or link to this item: https://doi.org/10.1088/0022-3727/39/13/002
Title: Influence of Co substitution for Fe on the magnetic properties of nanocrystalline (Nd,Pr)-Fe-B based alloys
Authors: Liu, Z.W. 
Davies, H.A.
Issue Date: 7-Jul-2006
Citation: Liu, Z.W., Davies, H.A. (2006-07-07). Influence of Co substitution for Fe on the magnetic properties of nanocrystalline (Nd,Pr)-Fe-B based alloys. Journal of Physics D: Applied Physics 39 (13) : 2647-2653. ScholarBank@NUS Repository. https://doi.org/10.1088/0022-3727/39/13/002
Abstract: The effects of Co substitution for Fe on the spin reorientation temperature, magnetic properties over a wide temperature range, the thermal stability and on exchange enhancement in nanocrystalline (Nd/Pr) z(Fe1-xCox)94-zB6 alloys have been comprehensively studied. Such Co substitution substantially increased the Curie temperature (TC) of the 2/14/1 phase and slightly decreased the spin reorientation temperature (TSR) for these alloys. Despite the smaller anisotropy field for the Nd2Co14B phase, in comparison with Nd2Fe14B, a small Co substitution did not greatly decrease the room temperature (RT) coercivity jHC, regardless of the rare earth to transition metal ratio. The remanence Jr at RT was generally slightly improved by Co substitutions up to ∼20%, though less so for the 8 at% rare earth (RE) series having a high volume fraction of soft magnetic phase. Similarly, substitution of up to 20% Co slightly enhanced the maximum energy product (BH)max at RT, except for the 8 at% RE alloys which showed a marked decline beyond 10 at% Co due to the strongly diminished jH C. In the case of the sub-ambient magnetic properties, Co substitution markedly decreased Jr and (BH)max, though the effect on jHC was much smaller. In contrast, Co additions, because of the enhancement of Tc, substantially improved the elevated temperature behaviour of all experimental alloys, by decreasing the values of the temperature coefficients for Jr and iHc, α and β, respectively, particularly for α. Moreover, the Co also reduced the irreversible losses in Jr and jHC measured on ribbon samples. Analysis of microstructural parameters governing the coercivity, using the modified Brown equation, suggested that Co substitution not only reduced the stray fields, by homogenizing the grain structure and smoothing the grain boundaries, but also improved the exchange coupling between grains. © 2006 IOP Publishing Ltd.
Source Title: Journal of Physics D: Applied Physics
URI: http://scholarbank.nus.edu.sg/handle/10635/96909
ISSN: 00223727
DOI: 10.1088/0022-3727/39/13/002
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

SCOPUSTM   
Citations

15
checked on Nov 13, 2019

WEB OF SCIENCETM
Citations

15
checked on Nov 4, 2019

Page view(s)

50
checked on Nov 9, 2019

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.