Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-11-28T21:27:33.206Z Has data issue: false hasContentIssue false
  • English
  • Français

New series of Sm2TM17 magnet materials for applications at temperatures up to 550°C

Published online by Cambridge University Press:  21 February 2011

Christina H. Chen ,
Marlin S. Walmer ,
Michael H. Walmer ,
Sam Liu ,
G. Edward Kuhl  and
Gerard K. Simon
Christina H. Chen
Affiliation:
Electron Energy Corp., 924 Links Ave., Landisville, PA 17538, USA
Marlin S. Walmer
Affiliation:
Electron Energy Corp., 924 Links Ave., Landisville, PA 17538, USA
Michael H. Walmer
Affiliation:
Electron Energy Corp., 924 Links Ave., Landisville, PA 17538, USA
Sam Liu
Affiliation:
University of Dayton, 300 College Park Ave., Dayton, OH 45469, USA
G. Edward Kuhl
Affiliation:
University of Dayton, 300 College Park Ave., Dayton, OH 45469, USA
Gerard K. Simon
Affiliation:
Air Force Research Laboratory, WPAFB, OH 45433, USA
Get access

Abstract

A new series of Sm(CowFevCuxZry)z magnet products with 1Hc up to 13 kOe at 400°C has been developed. These magnets have low temperature coefficients of iHc and a straight line B vs. H (extrinsic) demagnetization curve up to 550°C. A straight line extrinsic curve provides greater design flexibility and facilitates reduced size and weight of magnetic circuits. The straight line extrinsic demagnetization B curves are required for magnets used in dynamic applications. The maximum use temperature, defined here as TM, can be determined by finding the maximum temperature at which the B curve is a straight line. The results of this work show that increasing the Co content in the magnet enhances high temperature performance. A higher Co content provides a lower temperature coefficient β of iHe. Magnets with Co content w = 0.65 have β = 0.26%C from 25°C to 300°C. Magnets with w = 0.82 have β = 0.116%C from 25°C to 300°C. The lower β results in a higher (BH)max at high temperature, and a higher TM. The TM is 240°C for w = 0.65,330°C for w = 0.68, 400°C for w = 0.76, 490°C for w = 0.78, and 550°C for w = 0.82. By increasing the Co content and adjusting the content of other elements, along with appropriate changes of processing parameters, a new series of magnets has been developed for use at temperatures from 400°C to 550°C. Magnetic properties vs. temperature for the new series of magnets, in comparison to those of the best commercial magnets, are shown in this paper to illustrate the improvements which have been made. Magnetic properties at different temperatures vs. Co content for the series are also reported in this paper.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 577: Symposium H – Advanced Hard and Soft Magnetic Materials , 1999 , 277
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] Chen, C.H., Walmer, M.S., Walmer, M.H., Liu, S., Kuhl, E., Simon, G., “Sm2(Co,Fe,Cu,Zr)17 magnets for use at temperature ≥ 400°C”, 1998, J. Appl Phys. vol 83 (11), p.6706.Google Scholar
[2] Walmer, M.S., Chen, C.H., Walmer, M.H., Liu, S., Kuhl, G.E., Simon, G.K., “Use of heavy rare earth element Gd in RECo5 and RE2TM17 magnets for high temperature applications”, 1998, Proc. 15th Int. Workshop on Rare Earth Permanent Magnets and Their Applications, p. 689 Google Scholar
[3] Ray, A.E. and Strnat, K.J., “Easy directions of magnetism in ternary R2(Co, Fe)17 phase”, IEEE Trans. Magn., Vol 8, 1972, p. 516.Google Scholar
[4] Ray, A.E. and Liu, S., “recent progress in 2:17-type permanent magnets”, J. Materials Engineering and Performance, vol. 1, 1992, pp 183–191.Google Scholar
[5] Chen, Christina H., Walmer, Marlin S., Walmer, Michael H., Gong, Wei, and Ma, Bao-Min, “The relationship of thermal expansion to magnetocrystalline anisotropy, spontaneous magnetization and Tc for permanent magnets”, Appl. Phys. April, 1999, to be publishedGoogle Scholar
[6] Benz, M.G., Laforce, R.P., and Martin, D.L., “AIP Conf. Proc. 1974, No. 18/2, eds Graham, C.D. and Rhyne, J.J. (American Institute of Physics, New York) p. 1173 Google Scholar
[7] Jones, F.G. and Tokunaga, M., IEEE Trans. Magn., MAG–12, 1976, p. 968 Google Scholar
[8] Martis, R.J.J., Gupta, N., Sankar, S.G. and Rao, V.U.S., 1978, J. Appl. Phys., 49, p. 2070 Google Scholar
[9] Narasimhan, K.S.V.L., 1981, J. Appl. Phys., 52, p.2512 Google Scholar
[10] Li, D., Xu, E., Liu, J., and Du, Y., 1980, IEEE Trans. Magn., MAG–16, p. 988 Google Scholar
[11] Li, D., Liu, J., Zhou, S., Jin, X., and Xu, E., 1983, Proc. 7th Int. Workshop on Rare Earth Permanent Magnets and Their Applications, Beijing (China Academic Publishers), p. 495 Google Scholar
[12] Mildrum, H.F., Krupar, J.B. and Ray, A.E., 1983, J. Less-Common Met. 93, p. 261 Google Scholar
[13] Liu, S., Mildrum, H.F., and Strnat, K.J., “Demagnetization curves of four rare-earth-cobalt magnet types at temperatures 300-1000 K,” J. Appl. Phys. Vol.53, 1982, p. 2383.Google Scholar
[14] Liu, S. and Hoffman, E. P., “Application-oriented characterization of Sm2(Co,Fe,Cu,Zr)17 permanent magnets,” IEEE Trans. Magn., Vol. 32, 1996, p. 5091.Google Scholar
[15] Ma, B. M., Liang, Y. L., Patel, J., Scott, D., and Bounds, C. O., “The effect of Fe content on the temperature dependent magnetic properties of Sm(Co,Fe,Cu,Zr)z and SmCo5 sintered magnets at 450°C,” IEEE Trans. Magn., Vol. 32.1996, p. 4377.Google Scholar
[16] Liu, S., Hoffman, G. P., and Brown, J. R., “Long-term aging of Sm 2(Co,Fe,Cu,Zr)17 permanent magnets at 300 and 400°C,” IEEE Trans. Magn., Vol. 33, 1997, p. 3859.Google Scholar
[17] Kim, A., “High temperature stability of SmTM magnets,” J. Appl. Phys., Vol. 83, 1998, p. 6715.Google Scholar
[18] Liu, J.F., Ding, Y., and Hadjipanayis, G.C., “Effect of iron on the high temperature magnetic properties and microstructure of Sm2(Co,Fe,Cu,Zr)17 permanent magnets”, J. Appl. Phys., Vol. 85(3), 1999, p.1670 Google Scholar
[19] Liu, J.F., Chui, T., Dimitrov, D. and Hadjipanayis, G.C., “Abnormal temperature dependence of intrinsic coercivity in Sm(Co,Fe,Cu,Zr), powder materials”, Appl. Phys. Lett. Vol.73, 1998, p. 3007 Google Scholar
[20] Liu, J.F., Ding, Y., Dimitrov, D. and Hadjipanayis, G.C., “Microstructure and high temperature magnetic properties of Sm2(Co,Fe,Cu,Zr)17 (z = 6.7-9.1) permanent magnets”, Appl. Phys. Vol.85(5), 1999, p. 2800 Google Scholar
[21] Liu, J.F., Ding, Y., Dimitrov, D. and Hadjipanayis, G.C., “New rare earth permanent magnets with an intrinsic coercivity of 10 kOe at 773 K”,.Google Scholar
[22] Liu, Sam, Yang, Jie, Doyle, Gerorge, Kuhl, G.Edward, Chen, Christina, Walmer, Marlin, Walmer, Michael, and Simon, Gerard, “New sintered high temperature Sm-Co based permanent magnet materials”, Inter-Mag, 1999, to be published.Google Scholar