Hostname: page-component-848d4c4894-wg55d Total loading time: 0 Render date: 2024-05-03T10:14:37.738Z Has data issue: false hasContentIssue false

Strength and Ductility of Fe3Al with Addition of Cr

Published online by Cambridge University Press:  01 January 1992

D.G. Morris
Affiliation:
Institute of Structural Metallurgy, Avenue de Bellevaux 51, University of Neuchâtel, NEUCHATEL 2000, SWITZERLAND
M.M. Dadras
Affiliation:
Institute of Structural Metallurgy, Avenue de Bellevaux 51, University of Neuchâtel, NEUCHATEL 2000, SWITZERLAND
M.A. Morris
Affiliation:
Institute of Structural Metallurgy, Avenue de Bellevaux 51, University of Neuchâtel, NEUCHATEL 2000, SWITZERLAND
Get access

Abstract

The development of Fe3Al aluminides has been restricted in the past by poor ductility at ambient temperatures, and it is only recently that possible solutions to this problem have been found. It was shown a few years ago (1) that the addition of 2-6% Cr to a Fe3Al base alloy led to good ductility and this improvement was explained by a reduction of the APB energy, increasing the separation of the superpartial dislocations and thereby allowing easier dissociation of these dislocations, easier cross slip and a reduced tendency to stress and strain concentrations. However, at a later stage, an alternative explanation was proposed (2,3) based on examinations of both FeAl and Fe3Al alloys under different environments, and the ductility change was explained in terms of chemical attack at the tip of a crack leading to local hydrogen embrittlement.

The present study re-examines the behaviour of a Fe3Al alloy both with and without the addition of Cr. Strength, work hardening behaviour and failure ductility are examined under conditions where environmental effects should not be important, and the mechanical behaviour is interpreted in terms of significant variations in the type of order, the ordered domain structure and the resulting dislocation structures. It is seen that the addition of Cr can lead to a better ordered material and the differences in ordered state between the two materials can significantly affect dislocation behaviour and mechanical properties.

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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. McKamey, C.G., Horton, J.A. and Liu, C.T., J. Mater. Res. 4, 1156 (1989).Google Scholar
2. McKamey, C.G. and Liu, C.T., Scripta Metall. et Mater. 24, 2119 (1990).Google Scholar
3. Liu, C.T., Lee, E.H. and McKamey, C.G., Scripta Metall. 23, 875 (1989).Google Scholar
4. Crawford, R.C. and Ray, I.L.F., Phil. Mag. 35, 549 (1977).Google Scholar
5. Morris, D.G., Dadras, M.M. and Morris, M.A., Acta Metall. et Mater., in press.Google Scholar
6. Swann, P.R., Duff, W.R. and Fisher, R.M., Met. Trans. 3, 409 (1972).Google Scholar
7. Park, J.W. and Moon, I.G., Mater. Sci. and Eng. A152, 341 (1992).Google Scholar
8. Mendiratta, M.G., Ehlers, S.K. and Nathal, M.V., Met. Trans. 20A, 1701 (1989).Google Scholar
9. Morris, D.G., Phys. Stat. Sol. (a) 32, 145 (1975).Google Scholar
10. Ricolleau, C. and Loiseau, A., Proc. Conf. “iib 92”, Thessalonica, Greece, 21 June(1992).Google Scholar
11. Aoki, K. and Izumi, O., Nippon Kinzoku Gakkaishi, 43, 1190 (1979).Google Scholar
12. Liu, C.T., White, C.L. and Horton, J.A., Acta Metall. 33, 213 (1985).Google Scholar