Defects Distribution of Pr2Fe14B Hard Magnetic Magnet from Amorphous to Nanostructures Characterized by Positron Annihilation Spectroscopy

Article Preview

Abstract:

The defect distributions have been investigated using positron lifetime spectroscopy on amorphous and nanocrystalline Pr2Fe14B samples, produced by melt-spinning and nanocrystallization route. The main two components can be concluded that were ascribed to vacancy-like defects in the intergranular layers or the interfaces, and microvoids or large free volumes with size compared to several missing atoms at the interactions of the atomic aggregates or the crystallites. The remarkable changes in the positron lifetimes from the amorphous structure to the nanocrystalline with varied sizes can be interpreted, indicating that the structural transformation and the grain growth induce the defect distribution changes occurring at the interfaces with different shape and size.

You might also be interested in these eBooks

Info:

Periodical:

Materials Science Forum (Volumes 475-479)

Pages:

2123-2126

Citation:

Online since:

January 2005

Export:

Price:

Permissions CCC:

Permissions PLS:

Сopyright:

© 2005 Trans Tech Publications Ltd. All Rights Reserved

Share:

Citation:

[1] H. Kronmüller, R. Fischer, M. Bachmann, T. Leinweber: J. Mag. Mag. Mater. 203(1999), p.12.

Google Scholar

[2] Akinori Kojima, Akihiro Makino, Akihisa Inoue: J. Appl. Phys. 87(2000), pp.6576-6578.

Google Scholar

[3] H. Cleiter: Acta mater. 48(2000), p.1.

Google Scholar

[4] Jerzy Dryzek: J. Phys.: Condens. Matter. 12(200), p.137.

Google Scholar

[5] H. -E. Schaefer and K. Badura-Gergen: Defect and Diffusion Forum 143-147(1997), p.193.

Google Scholar

[6] J. -M. Greneche: J. Metastable and Nanocrystalline Mater. 1(1999), p.159.

Google Scholar

[7] R. Dittmar, R. Würschum, W. Ulfer and H. -E. Schaefer: Mater. Sci. Forum 255-257(1997), p.530.

Google Scholar

[8] J. Balogh, L. Bujdoso, D. Kaptas, T. Kemeny, I. Vincze, S. Szabo and D. L. Beke: Hyperfine Interactions 126(2000), p.171.

Google Scholar

[9] L. Pasquini, A. A. Rempel, R. Würschum, K. Reimann, M. A. Müller, B. Fultz, and H. -E. Schaefer: Phys. Rev. B 63 (2001), p.134114.

Google Scholar

[10] H. -E. Schaefer, R. Wüschum, M. Scheytt, R. Birringer and H. Gleiter: Mater. Sci. Forum, 15- 18(1987), p.955.

Google Scholar