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The Influence of Strain Rate on Dislocation Structures in γ/α2 Titanium Aluminides Deformed at 815°C

Published online by Cambridge University Press:  26 February 2011

W.T. Donlon ,
W.E. Dowling Jr.  and
J.E. Allison
W.T. Donlon
Affiliation:
Ford Motor Company, Research Staff, Dearborn, MI 48121–2053
W.E. Dowling Jr.
Affiliation:
Ford Motor Company, Research Staff, Dearborn, MI 48121–2053
J.E. Allison
Affiliation:
Ford Motor Company, Research Staff, Dearborn, MI 48121–2053
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Abstract

Elevated temperature (815°C) compression tests were performed at strain rates between 10−2 & 10−5 sec−1 on a γ/α2 alloy, Ti-48Al-1V-0.2C (at%), for two different α2 volume fractions. A large change in the flow stress was observed to occur for strain rates between 1.10−5 & 1.10−3 sec−1. The dislocations observed in the primary γ grains deformed at the high strain rates were “regular” 1/2<110]; screw dislocations. The dislocations observed at slow strain rates were also regular 1/2<110] dislocations, however their orientation was changed so that they were aligned close to [001]. Dislocation structures produced during high cycle fatigue are identical to those observed during high strain rate compression tests, while dislocation structures produced during tensile (ė- 8.10−4 sec−1 ) tests are identical to those observed in the slow strain rate compression tests. Analysis of the orientation of deformed primary γ-TiAl grains shows that the CRSS for {111}<101] slip must be at least 1.4 times the CRSS of {111}1/2<110] slip.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 213: Symposium Q – High-Temperature Ordered Intermetallic Alloys IV , 1990 , 297
Copyright
Copyright © Materials Research Society 1991

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References

REFERENCES

1. Shechtman, D., Blackburn, M.J., and Lipsitt, H.A., Met, Trans, 5 (1974), 1373–1381.Google Scholar
2. Hug, G., Loiseau, A., and Veyssiere, P., Phil, Mag. A 57 (3) (1988), 499–523.Google Scholar
3. Hall, E.L. and Huang, Shyh-Chin, J. Mater, Res., 4 (3) (1989), 595–602.Google Scholar
4. Kawabata, T., Abumiya, T., Kanai, T., and Izumi, O., Acta Met., 38 (8) (1990), 1381–1393.Google Scholar
5. Fujiwara, T. et al. , Phil, MAg, A, 61 (4) (1990), 591–606.Google Scholar
6. Court, S.A., Vasudevan, V.K., and Fraser, H.L., Phil, Mag, A, 61 (1) (1990), 141–158.Google Scholar
7. Microdev Software, 3120 NW John Olsen Ave., Hillsboro OR 97124.Google Scholar
8. Anisimov, , et al. , Phys. Met. Metall., 63 (2) (1987), 192–194.Google Scholar
9. Greenberg, B.F., et al. , Scripta Met., 22 (1988), 859–864.Google Scholar
10. Donlon, W.T., Dowling, W.E., and Allison, J.E., submitted for publication in TMS Symposia Proceedings: Microstructure/Property Relationships in Titanium Alloys and Titanium Aluminides,' ed. Kim, Y.W., Boyer, R., Hall, J. (Pittsburgh PA:TMS), 1991.Google Scholar