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The Character of Steps on Gamma/Alpha-2 Interfaces in a Low Misfit Lamellar TiAl-Based Alloy

Published online by Cambridge University Press:  10 February 2011

P. Shang ,
T.T. Cheng  and
M. Aindow
P. Shang
Affiliation:
School of Metallurgy & Materials,
T.T. Cheng
Affiliation:
Interdisciplinary Research Centre in Materials for High Performance Applications, The University of Birmingham. Birmingham, B15 2TT, UK
M. Aindow
Affiliation:
School of Metallurgy & Materials, Interdisciplinary Research Centre in Materials for High Performance Applications, The University of Birmingham. Birmingham, B15 2TT, UK
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Abstract

The defect character of steps on lamellar γ/α2 interfaces in a quinternary TiAl-based alloy has been studied using high resolution transmission electron microscopy. The interfaces consisted of atomically flat coherent terraces separated by interfacial steps across equal even numbers of {111}γ and (0002)α2 planes. Circuit mapping was used to identify the Burgers vectors of these steps from lattice images obtained at [101]γ and [110]γ zone axes. It was found that the Burgers vectors exhibited by the two-layer steps are different from those reported previously and are consistent with those expected for perfect disconnections as described by Pond's topological theory of interfacial defects, and not with the usual partial dislocation model.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 552: Symposium KK – High-Temperature Ordered Intermetallic Alloys VIII , 1998 , KK3.7.1
Copyright
Copyright © Materials Research Society 1999

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References

REFERENCES

1. Huang, S.C. and Hall, E.L., Metall. Trans. A, 22, 427 (1991).CrossRefGoogle Scholar
2. Kawabata, T., Tadano, M., and Izumi, O., Scripta Metall, 22, 1725 (1988).CrossRefGoogle Scholar
3. Mahon, G. J., and Howe, J. M., Metall. Trans., 21A, 1655 (1990).CrossRefGoogle Scholar
4. Zhao, L., and Tangri, K., Phil. Mag. A, 64, 361 (1991); Acta Metall Mater. 39, 2209 (1991); Phil. Mag. A, 65, 1065 (1992).CrossRefGoogle Scholar
5. Singh, S.R., and Howe, J.M., Phil. Mag. A, 66, 739 (1992).CrossRefGoogle Scholar
6. Yang, Y.S., Wu, S.K., and Wang, J.Y., Phil. Mag. A, 67, 463 (1993).CrossRefGoogle Scholar
7. Inui, H., Nakamura, A., Oh, M.H., and Yamaguchi, M., Ultramicroscopy. 39, 268 (1991); Phil. Mag. A, 66, 557 (1992).CrossRefGoogle Scholar
8. Pond, R.C., Dislocation in Solids, Vol.8, edited by Nabarro, F.R.N. (Amsterdam, North Holland, 1989), p. 1.Google Scholar
9. Cheng, T.T., and Loretto, M.H., in Structural Intermetallics 1997 eds. Nathal, M.V., Darolia, R., Liu, C.T., Martin, P.L., Miracle, D.B., Wagner, R. and Yamaguchi, M. (Warrendale, PA: TMS, 1997) p.253.Google Scholar
10. Shang, P., Cheng, T.T., and Aindow, M., Phil. Mag. A (in press).Google Scholar
11. Blackburn, M. J., The Science, Technology and Applications of Titanium, edited by Jaffee, R. and Promisel, N. E. (Oxford, England: Pergamon Press, 1970).Google Scholar
12. Hirth, J.P. and Pond, R.C., Acta Metall Mater. 44, 4749 (1996).CrossRefGoogle Scholar
13. Pond, R.C., Interface Sci., 2, 299 (1995); R.C. Pond, D.J. Bacon, and A. Serra, Phil. Mag. Lett, 71, 275 (1995).CrossRefGoogle Scholar
14. Dimitrakopulos, G.P., Karakostas, T., Antonopoulos, J.G., and Pond, R.C., Interface Sci., 5, 35 (1997).CrossRefGoogle Scholar