Self- and Impurity Diffusion in γ-TiAl Single Crystals

Abstract:

The diffusion coefficients of 44Ti, 63Ni and 59Fe in γ-TiAl single crystals have been measured by ion-beam sputter-sectioning technique, while those of In have been measured using ion implantation technique and secondary ion mass spectroscopy (SIMS) in order to clarify the diffusion anisotropy: the diffusion perpendicular and parallel to the [001] axis. The diffusion of Ti and In perpendicular to the [001] axis is faster than that parallel to the [001] axis. However, the diffusion anisotropies of Fe and Ni show opposite trend to those of Ti and In, namely the diffusion parallel to the [001] axis is faster than that perpendicular to the axis. The predominant process of diffusion perpendicular to the [001] axis has been discussed from a viewpoint of activation energy using the expression of the diffusion coefficients in L10-ordered alloys.

• Periodical: Defect and Diffusion Forum (Volumes 258-260)
• Pages: 259-269
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.258-260.259
• Online since: October 2006
• Authors: Hideo Nakajima, Y. Nose, Teruyuki Ikeda
• Keywords: γTiAl, Diffusion Anisotropy, Diffusion Mechanisms, Impurity Diffusion, L1₀-Ordered Structure, Self-Diffusion

References

[1] S. Kroll, H. Mehrer, N.A. Stolwijk, C. Herzig, R. Rosenkranz, GZ. Frommeyer, Defect Diffusion Forum Vols. 95-98 (1992), p.865.

DOI: 10.4028/www.scientific.net/ddf.95-98.865

[2] C. Herzig, T. Przeorsky, Y. Mishin, Intermetallics Vol. 7 (1999), p.389.

[3] C. Herzig, M. Friesel, D. Derdau, SV. Divinski, Intermetallics Vol. 7 (1999), p.1141.

[4] Y. Iijima, CG. Lee, SE. Kim, YT. Lee, HM. Kim, High Temp. Mater. Process. Vol. 18 (1999), p.305.

[5] Y. Mishin, C. Herzig, Acta Mater. Vol. 48 (2000), p.589.

[6] T. Ikeda, H. Kadowaki, H. Nakajima, H. Inui, M. Yamaguchi, Mater. Sci. Eng. A Vol. 312 (2001), p.155.

[7] T. Ikeda, H. Kadowaki, H. Nakajima, Acta Mater. Vol. 49 (2001), p.3475.

[8] N. Terashita, Y. Nosé, T. Ikeda, H. Nakajima, H. Inui, M. Yamaguchi, Mater. Lett. Vol. 57 (2003), p.3357.

[9] Y. Nosé, N. Terashita, T. Ikeda, H. Nakajima, Acta Mater. Vol. 54 (2006), p.2511.

[10] Y. Song, ZX. Guo, R. Yang, J. Light Metals Vol. 2 (2002), p.115.

[11] P. Shewmon: Diffusion in Solids (New York, McGraw-Hill 1963).

[12] Y. Mishin, private communication (2002).

[13] T.K. Nandy, D. Banerjee, AK. Gigia, Scripta Metall. Mater. Vol. 24 (1990), p. (2019).

[14] K. Hashimoto, H. Doi, T. Tsujimoto, T. Suzuki, Mater. Trans. JIM Vol. 7 (1991), p.574.

[15] H. Doi, K. Hashimoto, K. Kasahara, T. Tsujimoto, J. Jpn. Inst. Metals Vol. 56 (1992), p.232.

[16] Y.L. Hao, DS. Xu, Y.Y. Cui, R. Yang, D. Li, Acta Mater. Vol. 47 (1999), p.1129.

[17] H. Onodera, T. Abe, Titanium'95, Science and Technology (1995), p.80.