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Transmission Electron Microscopy of Fe2Nb Laves Phase with C14 structure in Fe-Nb-Ni Alloys

Published online by Cambridge University Press:  21 September 2018

Naoki Takata
Affiliation:
Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8552, JAPAN "Fundamental Studies on Technologies for Steel Materials with Enhanced Strength and Functions" Consortium of JRCM (The Japan Research and Development Center for Metals)
Shigehiro Ishikawa
Affiliation:
Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8552, JAPAN
Takashi Matsuo
Affiliation:
Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8552, JAPAN "Fundamental Studies on Technologies for Steel Materials with Enhanced Strength and Functions" Consortium of JRCM (The Japan Research and Development Center for Metals)
Masao Takeyama
Affiliation:
Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8552, JAPAN "Fundamental Studies on Technologies for Steel Materials with Enhanced Strength and Functions" Consortium of JRCM (The Japan Research and Development Center for Metals)
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Abstract

The lattice structure of the C14 Fe2Nb Laves phase with Ni in solution in Fe-Nb-Ni ternary alloys was examined by transmission electron microscopy. Binary stoichiometric Fe2Nb (Fe-33.3 at.% Nb) exhibits a featureless morphology with a low dislocation density. A similar morphology was observed in stoichiometric Fe2Nb containing 20 at.% Ni and in binary Fe-rich Fe2Nb (Fe-27.5 at.% Nb). In contrast, many planar faults parallel to the basal plane of the C14 structure were observed in Fe-rich Fe2Nb with Ni in solution, and the fault density increases with increasing Ni content up to 33.1 at.%. The high resolution transmission electron microscope (HRTEM) analysis revealed that the planar faults are related to the local change in the stacking sequence of the three 36-nets (triple layer) of the C14 structure. These results suggest that the presence of both, the point defects (Fe sublattice sites occupied by Ni atoms) and the anti-site defects (Nb sublattice sites occupied by excess Fe atoms), facilitate the formation of the planar faults.

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Articles
Copyright
Copyright © Materials Research Society 2009

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References

1. Gomi, N., Morita, S., Matsuo, T. and Takeyama, M., Report of JSPS 123rd Committee on Heat Resisting Materials and Alloys 42, 157 (2004).Google Scholar
2. Takeyama, M., Gomi, N., Morita, S. and Matsuo, T., Mater. Res. Soc. Symp. Proc. 842, 461 (2005).Google Scholar
3. Ishikawa, S., Matsuo, T. and Takeyama, M., Mater. Res. Soc. Symp. Proc. 980, 517 (2007).Google Scholar
4. Sugiura, T., Ishikawa, S., Mastuo, T. and Takeyama, M., Mater. Sci. Forum 561-565, 435 (2007).Google Scholar
5. Ishikawa, S., Matsuo, T., Takata, N. and Takeyama, M., in this book.Google Scholar
6. Ishizuka, K., Ultramicroscopy 5, 55 (1980).Google Scholar
7. Chisholm, M. F., Kumar, S. and Hazzledine, P., Science 307, 701 (2005).Google Scholar
8. Suzuki, H., Scientific Report Res. Inst. Tohoku Univ. A4, 455 (1952).Google Scholar
9. Saada, G., “Theory of Crystal Defects” ed. Gruber, B. (Academic press, 1966) pp. 167213.Google Scholar
10. Suzuki, H.Ten-iron Nyumon” (Agune, 1967) pp. 355.Google Scholar
11. Chu, F. and Pope, D. P., Mater. Sci. Eng. A170, 39 (1993).Google Scholar
12. Takasugi, T., Yoshida, M. and Hanada, S., Acta Mater. 44, 177 (1996).Google Scholar
13. Teatum, E. T., Gschneidner, K. A. Jr., Waber, J. T., “Compilation of Calculated Data Useful in Predicting Metallurgical Behavior of Elements in Binary Alloy Systems”, Report LA-4003, UC-25, Metal, Ceramics and Materials, TID-4500, Los Alamos Scientific Laboratory, (1968).Google Scholar
14. Thoma, D.J. and Perepezko, J.H., J. Alloys and Compd. 224, 330 (1995).Google Scholar