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High Rate Superplastic Deformation Mechanisms in IN90211 Mechanically Alloyed Aluminum

Published online by Cambridge University Press:  16 February 2011

Thomas R. Bieler  and
Amiya K. Mukherjee
Thomas R. Bieler
Affiliation:
Department of Metallurgy, Mechanics, and Materials Science, Michigan State University, East Lansing, MI 48824
Amiya K. Mukherjee
Affiliation:
University of California at Davis, Department of Mechanical Engineering, Division of Materials Science, Davis, CA 95616
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Abstract

IN90211 has exhibited superplastic elongations above 500% at high homologous temperatures (0.76–0.82 Tm). A high strain rate and flow stress for optimum elongation was measured (1–5/sec, 20–60 MPa, 425–485 °C). The apparent strain rate sensitivity of m≈0.25 differs from the usual m≈0.5 observations of superplastic deformation. An analysis of the data at several strains indicates a highly temperature dependent threshold stress is present, with either a n=2 or n=3 assumption for the stress exponent. The magnitude of the threshold stresses in IN90211 are smaller than usually observed in a dispersion strengthened matrix (1–20% instead of ≈50% of the Orowan stress). Experimental evidence from creep experiments supports the n=3 deformation mechanism as the rate limiting step of deformation.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 196: Symposium T – Superplasticity in Metals, Ceramics, and Intermetallics , 1990 , 259
Copyright
Copyright © Materials Research Society 1990

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References

REFERENCES

1. Blum, W. and Reppich, B., in Creep Behaviour of Crystalline Solids, edited by Wilshire, B. and Evans, R.W, (Pineridge Press Ltd., Swansea, U.K., 1985), pp. 100–106.Google Scholar
2. Mohamed, F.A. and Langdon, T.G., Acta Metall., 22, 779 (1974).Google Scholar
3. Bieler, T.R., Nieh, T.G., Wadsworth, J., and Mukherjee, A.K., Scripta Metall., 22, 81 (1988).Google Scholar
4. Bieler, T.R., Ph.D. dissertation, University of California at Davis, (University Microfilms, Ann Arbor, MI, 1989).Google Scholar
5. Bieler, T.R. and Mukherjee, A.K., Scripta Metall., in press.Google Scholar
6. Otsuka, M., Abe, Y., and Horiuchi, R., in Creep and Fracture of Engineering Materials and Structures, edited by Wilshire, B., Evans, R.W., (The Institute of Metals, London, 1987), pp. 307–317.Google Scholar
7. Nieh, T.G., Gilman, P.S., and Wadsworth, J., Scripta Metall., 19, 1375 (1985).Google Scholar
8. Kucharova, K., Orlova, A., Oikawa, H., and Cadek, J., Mat. Sci. & Eng. A102, 201–209 (1988).Google Scholar
9. Bieler, T.R., Goto, G.R., and Mukherjee, A.K., J. Mat. Sci., in press.Google Scholar
10. Mohamed, F.A., J. Mat. Sci. 18, 582–592 (1983).Google Scholar
11. Bieler, T.R. and Mukherjee, A.K., Mat. Sci. & Eng., in press.Google Scholar
12. Oliver, W.C. and Nix, W.D., Acta Metall., 30, 1335–47 (1982).Google Scholar
13. Mukhopadhyay, J., Mukherjee, A.K., and Mallik, A.K., J. Mat. Sci., 25, 977 (1990).Google Scholar
14. Gregory, J.K., Gibeling, J.C. and Nix, W.D., Met. Trans., 16A, 777 (1985).Google Scholar