Skip to main content Accessibility help
×
Home

Evidence of Embryo Formation as a Precursor to the Delta to Alpha-Prime Transformation in a Pu-Ga Alloy

  • Kerri J.M. Blobaum (a1), C. R. Krenn (a2), M. A. Wall (a3), T. B. Massalski (a4) and A. J. Schwartz (a5)...

Abstract

It was experimentally observed that a single Pu-2.0 at% Ga sample can be thermally cycled many times, with nearly the same amount of transformation and reversion during each cycle, provided that the sample is annealed at 375°C for 8 hours and then conditioned at 25°C for at least 6 hours. The ambient temperature conditioning period is crucial for obtaining the same amount of transformation to alpha-prime in each thermal cycle. Here, we present results from a series of experiments that investigate the effects of conditioning time and temperature on alpha-prime_formation. When the sample is conditioned at 25°C for times between 0 and 6 hours, the amount of alpha-prime formed is a function of conditioning time. For conditioning treatments between 6 and 70 hours, however, the amount of alpha-prime_formed is nearly constant. Conditioning treatments at –50°C, 150°C, and 370°C all resulted in less alpha-prime_formation than the 25°C treatments. We hypothesize that embryos of the thermodynamically stable alpha phase form during the conditioning treatments, and these embryos form alpha-prime upon subsequent cooling. This result is an indirect confirmation of the Russian Pu-Ga equilibrium phase diagram.

Copyright

References

Hide All
1. Hecker, S. S., Los Alamos Science 26, 290335 (2000).
2. Blobaum, K. J. M., Krenn, C. R., Mitchell, J. N., Haslam, J. J., Wall, M. A., Massalski, T. B., and Schwartz, A. J., Metall. Mater. Trans. A (accepted, 2005).
3. Chebotarev, N. T., Smotriskaya, E. S., Andrianov, M. A., and Kostyuk, O. E., in Plutonium 1975 and Other Actinides, edited by Blank, H. and Lindner, R., (Amsterdam, 1975), pp. 3746.
4. Hecker, S. S. and Timofeeva, L. F., Los Alamos Science 26, 244251 (2000).
5. Hecker, S. S., Harbur, D. R., and Zocco, T. G., Prog. Mater. Sci. 49, 429485 (2004).
6. Blobaum, K. J. M., Krenn, C. R., Haslam, J. J., Wall, M. A., and Schwartz, A. J., in Actinides–Basic Science, Applications, and Technology, edited by Soderholm, L., Joyce, J. J., Nicol, M. F., Shuh, D. K., and Tobin, J. G., (Mater. Res. Soc. Symp. Proc. 802, Pittsburgh, PA, 2003), pp. 3338.
7. Pijpers, T. F. J., Mathot, V. B. F., Goderis, B., Scherrenberg, R. L., and van der Vegte, E. W., Macromolecules 35, 36013613 (2002).
8. Timofeeva, L. F., in Ageing Studies and Lifetime Extension of Materials, edited by Mallinson, L. G., (New York, 2001), pp. 191198.
9. Fluss, M. J., Wirth, B. D., Wall, M., Felter, T. E., Caturla, M. J., Kubota, A., and Rubia, T. Diaz de la, J. Alloy. Compd. 368, 6274 (2004).10.1016/j.jallcom.2003.08.080
10. Dienes, G. J. and Damask, A. C., J. Appl. Phys. 29, 17131721 (1958).10.1063/1.1723032
11. Sizmann, R., J. Nucl. Mater. 69 & 70, 386412 (1968).
12. Lu, M., Lupu, C., and Rabalais, J. W., J. Phys.: Condens. Matter 16, R581-R602 (2004).

Keywords

Evidence of Embryo Formation as a Precursor to the Delta to Alpha-Prime Transformation in a Pu-Ga Alloy

  • Kerri J.M. Blobaum (a1), C. R. Krenn (a2), M. A. Wall (a3), T. B. Massalski (a4) and A. J. Schwartz (a5)...

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed