Hostname: page-component-7bb8b95d7b-5mhkq Total loading time: 0 Render date: 2024-10-05T01:26:01.987Z Has data issue: false hasContentIssue false

Analysis of Cavitation in a Near-γ Titanium Aluminide During High-Temperature/Superplastic Deformation

Published online by Cambridge University Press:  10 February 2011

Carl M. Lombard
Affiliation:
Air Force Research Laboratory, Materials and Manufacturing Directorate, AFRL/MLLM, Wright-Patterson Air Force Base, OH, 45433
Amit K. Ghosh
Affiliation:
Univ. of Michigan, Dept. of Materials Science & Engineering, Ann Arbor, MI, 48109
S. Lee Semiatin
Affiliation:
Air Force Research Laboratory, Materials and Manufacturing Directorate, AFRL/MLLM, Wright-Patterson Air Force Base, OH, 45433
Get access

Abstract

The superplastic flow behavior of a near-γ titanium aluminide (Ti-45.5Al-2Cr-2Nb) is determined under uniaxial tension in as-rolled or rolled-and-heat treated conditions (1177°C/4 hr or 1238°C/2 hr). Cavitation characteristics, including cavity growth rates, are established via isothermal, constant strain rate tests conducted at 10−4 to 10−2 s−1 and temperatures between 900°C and 1200°C. Differences in cavitation as a function of initial structure, strain, strain rate and temperature are noted. Cavity growth is found to be largely plasticity controlled. Experimental growth rates are compared with equations that predict rates as a function of strain rate sensitivity. Although the equations assume no coalescence and no nucleation of new cavities, which are experimentally observed, they are useful in predicting actual growth rates.

Type
Research Article
Copyright
Copyright © Materials Research Society 2000

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

1. Semiatin, S.L., Seetharaman, V., and Jain, V.K., Met. Trans. A, 25A, pp. 27532768 (1994).10.1007/BF02649227Google Scholar
2. Lee, W.B., Yang, H.S., Kim, Y.-W. and Mukherjee, A.K., Scripta Met. Mater., 29, pp. 14031408 (1993).10.1016/0956-716X(93)90327-OGoogle Scholar
3. Lombard, C.M., Ghosh, A.K. and Semiatin, S.L., Proceedings of Gamma Titanium Aluminides Symposium, eds. Kim, Y.-W., Wagner, R. and Yamaguchi, M. (TMS, Warrendale, PA 1995) pp. 579586.Google Scholar
4. Ridley, N. and Pilling, J., Superplasticity, eds. Baudelet, B. and Suery, M.; (CNRS, Paris, 1985), Ch. 8.Google Scholar
5. Pilling, J. and Ridley, N., Acta Metall., 34, pp. 669679 (1986).10.1016/0001-6160(86)90182-3Google Scholar
6. Cocks, A.C.F. and Ashby, M.F., Progress in Matl. Sci., 27, pp. 189244 (1982).10.1016/0079-6425(82)90001-9Google Scholar
7. Suery, M., Superplasticity, eds. Baudelet, B. and Suery, M.; (CNRS, Paris, 1985), Ch. 9.Google Scholar
8. Budiansky, B., et al. , Mechanics of Solids, eds. Hopkins, H. G. and Sewell, M. J.; (Pergamon Press, Oxford, 1982).Google Scholar
9. Stowell, M.J., Metal Sci., 14, pp. 267271 (1980).10.1179/030634580790426373Google Scholar
10. Lian, J. and Suery, M., Mat. Sci. Tech., 2, pp. 1093–8 (1986).10.1179/mst.1986.2.11.1093Google Scholar
11. Nicolaou, P., Semiatin, S.L., and Lombard, C.M., Met. Trans. A, 27A, pp. 3112–9 (1996).10.1007/BF02663861Google Scholar
12. NIH Image public domain, image analysis computer program (developed at the U.S. National Institutes of Health and available from the Internet at zippy.nimh.nih.gov).Google Scholar
13. Lombard, C.M., Ghosh, A.K. and Semiatin, S.L., Superplasticity and Superplastic Forming 1998, eds. Ghosh, A. K. and Bieler, T. R., (TMS, Warrendale, PA,1998), pp. 267275.Google Scholar
14. Lian, J and Suery, M., Mat. Sci. Tech., 2, pp. 10931098 (1986).10.1179/mst.1986.2.11.1093Google Scholar
15. Sneary, P.R., Beals, R. S and Bieler, T.R., Scripta Mat., 34, pp. 16471654 (1996).10.1016/1359-6462(96)00023-1Google Scholar
16. Lee, D. and Backofen, W., Trans. Met. Soc. AIME, 239, pp. 10341040 (1967).Google Scholar