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Decomposition and dissolution kinetics ofδ′ precipitation in Al-Li binary alloys

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Abstract

Aside from its technological importance, the Al-Li alloy system also exhibits interesting phase transformations involving both equilibrium and metastable states. Recent theoretical studies have shown that a supersaturated solid solution could take different transformation paths when it is quenched into theα +γ′ field. Suggestions were made that a rapidly quenched solution phase should first undergo a congruent ordering transformation before it decomposes into a two-phase mixture by either a secondary spinodal decomposition or the classical nucleation and growth process. Moreover, a metastable miscibility gap was predicted at lower temperatures. The objective of this research is to study the transformation paths and dynamics in Al-Li binary alloys of three compositions (5.2, 7.0, and 12.0 at. pct Li). This investigation emphasizes thein situ small-angle X-ray scattering (SAXS) observations on specimens subjected to various aging conditions. Special attention is paid to the early stages of the transformation in an attempt to characterize the various possible modes of phase separation on one hand and to study the dynamics of the precipitation process on the other. The following results are obtained: the congruent ordering precedes decomposition at low temperatures; the metastableγ′ solvus curve is reconfirmed; but the predicted metastable miscibility gap is not found. Guinier radii measurements of the particles showed Ostwald ripening is quickly reached upon heating to the aging temperatures. Slowing down behavior is seen at aging temperatures close to the solvus boundary. Activation energies for Li diffusion were obtained using the modified Lifshitz, Slyozov, and Wagner (MLSW) model. A test of dynamical scaling behavior is carried out for the Al-12.0 at. pct Li alloy.

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References

  1. S.-W. Chen, C.-H. Jan, J.-C. Lin, and Y.A. Chang:Proc. 5th Int. Corf, on Aluminum-Lithium Alloys, E. Starks and T. Sanders, eds., Materials and Component Engineering Pub. Ltd., Birmingham, UK, 1989.

    Google Scholar 

  2. C. Sigli and J.M. Sanchez:Acta Metall., 1986, vol. 34, pp. 1021–28.

    Article  CAS  Google Scholar 

  3. N.S. Golosov, L.E. Popov, and G.S. Golosova:J. Sov. Phys., 1971, pp. 459–72.

  4. M.A. Dvorack, J.E. Epperson, and H. Chen:Acta Metall., 1986, vol. 34, pp. 117–24.

    Article  CAS  Google Scholar 

  5. A.G. Khachaturyan, T.F. Lindsey, and J.W. Morris, Jr.:Metall. Trans. A, 1988, vol. 19A, pp. 249–58.

    CAS  Google Scholar 

  6. H.-T. Li and H. Chen:J. Appl. Crystallogr., 1989, vol. 22 (4), pp. 302–04.

    Article  Google Scholar 

  7. J. Lendvai, H.-J. Gudladt, W. Wunderlich, and V. Gerold:Proc. 5th Int. Conf. on Aluminum-Lithium Alloys, E. Starks and T. Sanders, eds., Materials and Component Engineering Pub. Ltd., Birmingham, UK, 1989.

    Google Scholar 

  8. S. Miyasato and G. Thomas:Proc. 5th Int. Conf. on Aluminum-Lithium Alloys, E. Starks and T. Sanders, eds., Materials and Component Engineering Pub. Ltd., Birmingham, UK, 1989.

    Google Scholar 

  9. A. Guinier and G. Fournet:Small-Angle Scattering of X-Rays, John Wiley & Sons, New York, NY, 1955.

    Google Scholar 

  10. I.M. Lifshitz and V.V. Slyozov:J. Phys. Chem. Solids, 1961, vol. 19, pp. 35–50.

    Article  Google Scholar 

  11. C. Wagner:Z. Electrochem., 1961, vol. 65, pp. 581–91.

    CAS  Google Scholar 

  12. A.D. Brailsford and P. Wynblatt:Acta Metall., 1979, vol. 27, pp. 489–97.

    Article  CAS  Google Scholar 

  13. J.A. Marqusee and J. Ross:J. Chem. Phys., 1983, vol. 79, pp. 373–78.

    Article  CAS  Google Scholar 

  14. P.W. Voorhees and M.E. Glicksman:Acta Metall., 1984, vol. 32, pp. 2001–11.

    Article  CAS  Google Scholar 

  15. K. Osamura, H. Okuda, Y. Amemiya, and H. Hashizume:Dynamics of Ordering Processes, S. Komura and H. Furukawa, eds., 1989, pp. 273–80.

  16. J.P. Gunton, M. San Miguel, and P.S. Sahni:Phase Transitions and Critical Phenomena, C. Domb and J.L. Lebowitz, eds., Academic Press, New York, NY, 1983, vol. 8, pp. 267–466.

    Google Scholar 

  17. H. Furukawa:Physica, 1984, vol. A123, pp. 497–515.

    Google Scholar 

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Authors and Affiliations

  1. CSIST, Long-Tan, Taiwan, Republic of China

    B. J. Shaiu (Senior Engineer)

  2. Harbin Institute of Technology, Harbin, People’s Republic of China

    H. T. Li (Lecturer)

  3. Department of Materials Science and Engineering, University of Illinois, 61801, Urbana, IL

    H. Y. Lee (Research Associate) & Haydn Chen (Professor)

Authors
  1. B. J. Shaiu
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  2. H. T. Li
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  3. H. Y. Lee
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  4. Haydn Chen
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Formerly Visiting Scientists at the University of Illinois

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Shaiu, B.J., Li, H.T., Lee, H.Y. et al. Decomposition and dissolution kinetics ofδ′ precipitation in Al-Li binary alloys. Metall Trans A 21, 1133–1141 (1990). https://doi.org/10.1007/BF02656533

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  • DOI: https://doi.org/10.1007/BF02656533

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