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Plastic Deformation Behavior of Al5Ti3 Single-Phase Single Crystals

Published online by Cambridge University Press:  11 February 2011

Takayoshi Nakano
Affiliation:
Department of Materials Science and Engineering & Handai Frontier Research Center, Graduate School of Engineering, Osaka University, 2–1, Yamada-oka, Suita, Osaka 565–0871, JAPAN
Koutaro Hayashi
Affiliation:
Department of Materials Science and Engineering & Handai Frontier Research Center, Graduate School of Engineering, Osaka University, 2–1, Yamada-oka, Suita, Osaka 565–0871, JAPAN
Yosuke Nagasawa
Affiliation:
Department of Materials Science and Engineering & Handai Frontier Research Center, Graduate School of Engineering, Osaka University, 2–1, Yamada-oka, Suita, Osaka 565–0871, JAPAN
Yukichi Umakoshi
Affiliation:
Department of Materials Science and Engineering & Handai Frontier Research Center, Graduate School of Engineering, Osaka University, 2–1, Yamada-oka, Suita, Osaka 565–0871, JAPAN
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Abstract

Al5Ti3 single-phase single crystals with the stoichiometric composition of Ti-62.5at.%Al were obtained by the floating zone method and subsequent heat treatment at 750°C for 48h. The crystals contain no L10 phase, but compose of anti-phase domains (APD) surrounded by the anti-phase boundary (APB) on the basis of the Al5Ti3 long-period superstructure.

Orientation dependence of plastic deformation behavior and operative slip system were examined in compression in a wide temperature range between RT and 750°C using the single-phase single crystals in comparison with Al-rich TiAl single crystals with the L10 matrix and Al5Ti3 precipitates. In the wide crystal orientation area, {111)<110] ordinary slip appeared independent of the tested temperature, while {111)<101] superlattice slip was operative only at around [001] and [110] axes. This is because the critical resolved shear stress (CRSS) for the ordinary slip is lower than that for the superlattice slip and that for the ordinary slip in other Al-rich TiAl crystals containing L10. This implies that existence of the L10 matrix with the Al5Ti3 phase must be closely related to strengthening for the ordinary slip, similarity in Ni-base super-alloys consisting of the Ni-based matrix and L12 precipitates. The CRSS for both slips gradually decreased or was kept constant with temperature, showing no remarkable anomalous strengthening.

In this paper, deformation mechanism in Al5Ti3 single-phase single crystals will be discussed focusing on condition of the Al5Ti3 superstructure.

Type
Research Article
Copyright
Copyright © Materials Research Society 2003

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References

REFERENCES

[1] Nakano, T., Matsumoto, K., Seno, T., Oma, K. and Umakoshi, Y., Phil. Mag. A 74, 251 (1996).Google Scholar
[2] Nakano, T., Hagihara, K., Seno, T., Sumida, N., Yamamoto, M. and Umakoshi, Y., Phil. Mag. Lett. 78, 385 (1998).Google Scholar
[3] Nakano, T., Hayashi, K., Ashida, K. and Umakoshi, Y., MRS Proc., High Temperature Ordered Intermetallic Alloys, 646, pp. KK5.9.1 (1998).Google Scholar
[4] Nakano, T., Negishi, A., Hayashi, K. and Umakoshi, Y., Acta Mater. 47, 1193 (1999).Google Scholar
[5] Gregori, F. and Veyssiere, P., Phil. Mag. A 79, 403 (1999).Google Scholar
[6] Hayashi, K., Nakano, T. and Umakoshi, Y., Sci. Technology Advanced Mater. 2, 433 (2001).Google Scholar
[7] Jiao, S., Bird, N., Hirsch, P. B. and Taylor, G., Phil. Mag. A 81, 213 (2001).Google Scholar
[8] Inui, H., Chikugo, K., Nomura, K. and Yamaguchi, M., Mat. Sci. Engng. A 329, 377 (2002).Google Scholar
[9] Loiseau, A., Lasalmonie, A., Van. Tendeloo, G., Van. Landuyt, J. and Amelinckz, S., Acta Crystallogr. B41, 411 (1985).Google Scholar
[10] Kulkarni, U. D., Acta Mater. 46, 1193 (1998).Google Scholar
[11] Stein, F., Zhang, L. C., Sauthoff, G. and Palm, M., Acta Mater. 49, 2919 (2001).Google Scholar
[12] Zhang, L. C., Palm, M. and Stein, F., Intermetallics 9, 229 (2001).Google Scholar
[13] Nakano, T., Hayashi, K. and Umakoshi, Y., Phil. Mag. A 82, 763 (2002).Google Scholar
[14] Kulkarni, U. D., Phil. Mag. A 82, 1017 (2002).Google Scholar
[15] Hata, S., Higuchi, K., Itakura, M., Kuwano, N., Nakano, T., Hayashi, K. and Umakoshi, Y., Phil. Mag. Lett. 82, 363 (2002).Google Scholar
[16] Palm, M., Zhang, L. C., Stein, F. and Sauthoff, G., Intermetallics 10, 523 (2002).Google Scholar
[17] Doi, M., Koyama, T., Taniguchi, T. and Naito, S., Mat. Sci. Engng. A 329, 891 (2002).Google Scholar
[18] Hayashi, K., Nakano, T. and Umakoshi, Y., Intermetallics 10, 771 (2002).Google Scholar
[19] Nakano, T., Nagasawa, Y., Hata, S., Itakura, K., Tomokiyo, T., Kuwano, N. and Umakoshi, Y., unpublished data, (2002).Google Scholar
[20] Beardmore, P., Davies, R. G. and Johnston, T. L., Trans. Metall. Soc. AIME 245, 1537 (1969).Google Scholar