Hostname: page-component-848d4c4894-nmvwc Total loading time: 0 Render date: 2024-07-03T04:26:11.815Z Has data issue: false hasContentIssue false
  • English
  • Français

Hrtem Studies of Dislocations and Interfaces in TiAl

Published online by Cambridge University Press:  10 February 2011

M. J. Mills ,
J. M.K. Wiezorek  and
H. L. Fraser
M. J. Mills
Affiliation:
Department of Materials Science and Engineering, The Ohio State University, Columbus, OH 43210
J. M.K. Wiezorek
Affiliation:
Department of Materials Science and Engineering, The Ohio State University, Columbus, OH 43210
H. L. Fraser
Affiliation:
Department of Materials Science and Engineering, The Ohio State University, Columbus, OH 43210
Get access

Abstract

In this paper, we summarize the results of high resolution transmission electron microscopy investigations of the structure of dislocations and interphase boundaries in Ti-Al alloys. Dislocations of the type 1/2<110] and 1/2<112] have been examined in 60° and 90° orientations, respectively, in single-phase Ti-52 at%Al. The former dislocation exhibits an extremely compact core configuration, suggesting a high complex stacking fault energy, while the latter is dissociated the scale of several nanometers in a coupled intrinsic/extrinsic stacking fault configuration. Two types of α2/γ interface structures have been observed in nearly fully-lamellar Ti-48 at%Al. The first is consistent with the common observation of structural ledges due to 1/6<112> dislocations in the interface plane. The second interface type consists of a quasi-periodic array of 1/2<110] dislocations which do not lie in the interface, and appear to be contained wholy within the γ phase. The possible implications of these observations with respect to the mechanical behavior of both single-phase γ and two-phase lamellar microstructures are discussed.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 466: Symposium G – Atomic Resolution Microscopy of Surfaces and Interfaces , 1996 , 131
Copyright
Copyright © Materials Research Society 1997

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Kim, Y.M. and Dimiduk, D.M., J. of Metals 43, 40 (1991).Google Scholar
2. Hemker, K.J., Viguier, B. and Mills, M.J., Mater. Sei. Eng. A164, 391 (1993).Google Scholar
3. Simmons, J.P., Mills, M.J. and Rao, S.I., Mat. Res. Soc. Symp. 364, 137 (1995).Google Scholar
4. Inkson, B.J. and Humphreys, C.J., Phil. Mag. 71, 307 (1995).Google Scholar
5. Greensburg, B.A., Antonova, O.V., Indenbaum, V.N., Karkina, L.E., Notkin, A.B., Ponomarev, M.V. and Smirnov, L.V., Acta Metall. Mater. 39, 233 (1991).Google Scholar
6. Hug, G., Loiseau, A. and Lasalmonie, A., Phil. Mag. A 54, 47 (1986).Google Scholar
7. Sriram, S., Vasudevan, V. and Dimiduk, D., Mat. Res. Soc. Symp. Proc. 364, 647 (1995).Google Scholar
8. Woodward, C., MacLauren, J. M. and Rao, S. I., J. Mater. Res., 7, 1735 (1992).Google Scholar
9. Fu, C.L. and Yoo, M.H., J. Intermetallics 1, 59 (1993).Google Scholar
10. Morris, M. A., Phil. Mag. A, 69, 129 (1994).Google Scholar
11. Whang, S. H. and Hahn, Y. D., Scripta metall. mater., 24, 485 (1990).Google Scholar
12. Viguier, B., Hemker, K.J., Bonneville, J., Louchet, F. and Martin, J.L., Phil. Mag A 71, 1295 (1995).Google Scholar
13. Baluc, N., Ph D.Thesis. Ecole Polytechnique Federale, Lausanne (1990).Google Scholar
14. Crimp, M. A., Phil. Mag. Lett. 60, 45 (1989).Google Scholar
15. Mills, M. J., Simulation of Electron Diffraction Images, eds. Krakow, W. A. and O'Keefe, M. A. (The Metallurgical Society), p. 210 (1989).Google Scholar
16. Sriram, S., Hazzledine, P. M., Dimiduk, D. M. and Vasudevan, V., Phil. Mag. A, in press.Google Scholar
17. Hug, G. and Veyssiere, P. in Proceedings of the International Conference on Electron Micros copy in Plasticity and Fracture Research of Materials, edited by Messerschmidt, U., Appel, F., Heydenreich, J. and Schmidt, V. (Akademie, Berlin, 1989), 451.Google Scholar
18. Yamaguchi, M. and Inui, H., Structural Intermetallics. edited by Darolia, R. et al., (TMS, 1993), p. 127.Google Scholar
19. Zhao, L. and Tangri, K., Acta. Metall. Mater. 39, 2209 (1991).Google Scholar
20. Mahon, G.J. and Howe, J.M., Met. Trans. A 21, 1655 (1990)Google Scholar
21. Singh, S.R. and Howe, J.M., Phil. Mag. A, 66, 739 (1992)‥Google Scholar
22. Popoola, O., Cordier, C., Pirouz, P. and Heuer, A.H., Scripta Metall. Mater. 26, 1643 (1992).Google Scholar
23. Yang, Y.S. and Wu, S.K., Phil. Mag. A 65, 15 (1992).Google Scholar
24. Wunderlich, W., Frommeyer, G. and Czarnowski, P., Mater. Sei. Eng. A164, 421 (1993).Google Scholar
25. Yang, Y.S. and Wu, S.K. and Wang, J.Y, Phil. Mag. A 67, 463 (1993).Google Scholar
26. Appel, F., Beaven, P.A. and Wagner, R., Acta. Metall. Mater. 41, 1721 (1993).Google Scholar