Hostname: page-component-586b7cd67f-dlnhk Total loading time: 0 Render date: 2024-11-25T15:24:27.851Z Has data issue: false hasContentIssue false
  • English
  • Français

Magnetic Characteristics of RCo7−xZrx Alloys (invited) (R = Sm, Pr, Er, Gd, and Y)

Published online by Cambridge University Press:  21 February 2011

M.Q. Huang ,
W.E. Wallace ,
M.E. Mchenry ,
S.G. Sankar ,
Qun Chen  and
B.M. Ma Rhodia
M.Q. Huang
Affiliation:
Advanced Materials Corporation, Pittsburgh, PA 15230 Department of Materials Science and Engineering, Carnegie Mellon University Pittsburgh, PA 15213
W.E. Wallace
Affiliation:
Department of Materials Science and Engineering, Carnegie Mellon University Pittsburgh, PA 15213
M.E. Mchenry
Affiliation:
Department of Materials Science and Engineering, Carnegie Mellon University Pittsburgh, PA 15213
S.G. Sankar
Affiliation:
Advanced Materials Corporation, Pittsburgh, PA 15230
Qun Chen
Affiliation:
Inc/Chem Dist. Center, CN7500, Cranbury, NJ 08512
B.M. Ma Rhodia
Affiliation:
Inc/Chem Dist. Center, CN7500, Cranbury, NJ 08512
Get access

Abstract

A brief review is presented of recent work dealing with the structure and magnetic properties of RCo7−x Zrx alloys (R=Sm, Pr, Er, Gd, and Y). The experimental results obtained are consistent with a model in which Zr atoms partly replace dumbbell Co atoms and play an important role in stabilizing the TbCu7 structure while significantly increasing the anisotropy field (HA). For example, when R=Sm, HA increases from 90 kOe for x=O to 130 kOe for x=0.2 at 300 K, and from 140 kOe for x=0 to 220 kOe for x=0.2 at 10 K. In the case of R=Y and Gd, HA is mainly contributed by the Co sublattice. For R=Y alloys, HA increases from 18 kOe for x=0 to 74 kOe for x=0.2 at 300 K and from 20 kOe for x=0 to 82 kOe for x=0.2 at 10 K. For R=Gd alloys, HA shows the largest enhancement. It increases from 35 kOe for x=0 to 140 kOe for x=0.2 at 300 K and from planar for x=0 to uniaxial with 182 kOe for x=0.2 at 10 K. In general, experimental results are in accord with the theory of Greedan and Rao for anisotropies of R-Co alloys. The magnetic moments for cobalt and rare earth in RCo7−xrx compounds (x=0∼A).2) have been estimated from the experimental values. The results show that they are nearly the same as those in RCo5 or R2Co17. The Co moment is 1.5∼;1.6 μB. Some phase transition phenomenon between RCo5, RCo7, R2Co17and R2Co7at different heat treatment conditions will also be discussed.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 577: Symposium H – Advanced Hard and Soft Magnetic Materials , 1999 , 97
Copyright
Copyright © Materials Research Society 1999

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Khan, Y., Acta Cryst. B29, 2501 (1973)Google Scholar
2. Saito, H., Takahashi, M., Wakiyama, T., Kodo, G., and Nakagawa, H., J. Magn. Magn. Mater. 82, 322 (1989)Google Scholar
3. Buschow, K. H. J. and Broeder, F. J. A. den, J. Less-Common Met. 3, 191 (1973)Google Scholar
4. Yang, J., Mao, O. and Altounian, Z., IEEE Trans. Magn. 32, 4390 (1987)Google Scholar
5. Mortia, Y., Umeda, T. and Kimura, Y., IEEE Trans. Magn. 23, 2702 (1987)Google Scholar
6. Fukui, Y., Nishio, T. and Iwama, Y., IEEE Trena. Magn. 23, 2705 (1987)Google Scholar
7. Liu, S., Midrum, H.F. and Strnat, K.J., J.Appl.Phys. 53 (3) 2383 (1982)Google Scholar
8. Ojima, T., Tomizawa, S., Yoneyama, T., and Hari, I., IEEE Trans. Magn. 13, 1317 (1977)Google Scholar
9. Fujii, H., Satyanaryana, M. V. and Wallace, W.E., Solid State Comm., 41, 445 (1982)Google Scholar
10. Huang, M.Q., Wallace, W.E., McHenry, M.E., Chen, Q. and Ma, B. M., J. Appl. Phys., 83, 6718 (1998)Google Scholar
11. Huang, M.Q., Drennan, M., Wallace, W.E., McHenry, M.E., Chen, Q. and Ma, B.M., J.Appl. Phys., (1999) (in press)Google Scholar
12. Derkaui, S., Valignat, N. and Alibert, C.H., J. Alloy, Comm. 232, 296(1996)Google Scholar
13. Buschow, K.H. J., J.Less-Common Met. 33, 311 (1973)Google Scholar
14. Wallace, W.E., Prog. Solid St. Chem, 16, 127 (1985)Google Scholar
15. Greedan, J.E. and Rao, V.U.S., J. Solid State Chem., 6, 387 (1973).Google Scholar