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Grain Boundary Engineering in Ordered Ni3Al for Improving Ductility

Published online by Cambridge University Press:  10 February 2011

T. K. Chaki*
Affiliation:
State University of New York, Department of Mechanical and Aerospace Engineering, Buffalo, NY 14260
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Abstract

Several techniques of grain boundary engineering for improving ductility in polycrystalline Ni3Al are discussed with the plausible mechanism. Single crystals of Ni3Al are ductile at room temperature, but polycrstalline Ni3Al fails intergranularly with little elongation. The grain boundaries are also embrittled by environmental moisture. The weakness of the boundaries is attributed to the presence of crack-like microcavities at the boundaries. Microalloying with B closes up the microcavities by enhancing relaxation of Ni and Al atoms, thereby improving ductility. In directionally solidified Ni3Al containing low-angle boundaries, large ductility has been reported. Polycrystalline N?3AI produced by recrystallization of rolled single crystals contains a large fraction of Σ3 boundaries and exhibits large ductility. Due to good matching, the low-angle and Σ3 grain boundaries do not contain microcavities and consequently are strong.

Type
Research Article
Copyright
Copyright © Materials Research Society 1997

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References

REFERENCES

1. Copley, S.M. and Kear, B.H., Trans. Metall. Soc. AIME 239, 977 (1967).Google Scholar
2. Ogura, T., Hanada, S., Masumoto, T., and Izumi, O., Metall. Trans. A 16, 441 (1985).Google Scholar
3. Liu, C.T., Scripta Metall. Mater. 27, 25 (1992).Google Scholar
4. Aoki, K. and Izumi, O., J. Japan Inst. Metals 43, 1190 (1979).Google Scholar
5. Liu, C.T., White, C.L., and Horton, J.A., Acta Metall. 33, 213 (1985).Google Scholar
6. Horton, J.A. and Miller, M.K., Acta Metall. 35, 133 (1987).Google Scholar
7. Masahashi, N., Takasugi, T., and Izumi, O., Acta Metall. 36, 1823 (1988).Google Scholar
8. Wan, X.J., Zhu, J.H., and Jing, K.L., Scripta Metall. Mater. 26, 473 (1992).Google Scholar
9. M.O. Speidel in Hydrogen in Metals, edited by Bernstein, I.M. and Thompson, A.W. (American Society of Metals, Metals Park, OH, 1974), pp. 249276.Google Scholar
10. Otterbein, U., Hofmann, S., and Ruhle, M. in High-Temperature Ordered Intermetallic Alloys V, edited by Baker, I., Darolia, R., Whittenberger, J.D., and Yoo, M.H. (Materials Research Society, Pittsburgh, PA, 1993), pp. 183188.Google Scholar
11. Schulson, E.M., Weihs, T.P., Baker, I., Frost, H.J., and Horton, J.A., Acta Metall. 34, 1395 (1986).Google Scholar
12. King, A.H. and Yoo, M.H., Scripta Metall. 21, 1115 (1987).Google Scholar
13. Swiatnicki, W.A. and Grabski, M.W., Acta Metall. 37, 1307 (1989).Google Scholar
14. Krzanowski, J.E., Scripta Metall. 23, 1219 (1989).Google Scholar
15. George, E.P., Liu, C.T., and Padgett, R.A., Scripta Metall. 23, 979 (1989).Google Scholar
16. CForwood, T. and Gibson, M.A., Philos. Mag. A 66, 1121 (1992).Google Scholar
17. Hirano, T. and Mawari, T., in High-Temperature Ordered Intermetallic Alloys V, edited by Baker, I., Darolia, R., Whittenberger, J.D., and Yoo, M.H. (Materials Research Society, Pittsburgh, PA, 1993), pp. 691696.Google Scholar
18. George, E.P., Liu, C.T., and Pope, D.P., Scripta Metall. Mater. 27, 365 (1992).Google Scholar
19. Reed-Hill, R.E. and Abbaschian, R., Physical Metallurgy Principles, 3rd edition (PWS-Kent, Boston, MA, 1992), p. 200.Google Scholar
20. Takasugi, T. and Izumi, O., Acta Metall. 31, 1187 (1983).Google Scholar
21. Kruisman, J.J., Vitek, V., and Th, J.. De Hosson, M., Acta Metall. 36, 2729 (1988).Google Scholar
22. Chen, S.P., Voter, A.F., Albers, R.C., Boring, A.M., Hay, P.J., J. Mater. Res. 5, 955 (1990).Google Scholar
23. Masahashi, N., Takasugi, T., and Izumi, O., Acta Metall. 36, 1815 (1988).Google Scholar
24. Dasgupta, A., Smedskjaer, L.C., Legnini, D.G., and Siegel, R.W., Mater. Lett. 3, 457 (1985).Google Scholar
25. Fu, C.L. and Yoo, M.H., Mater. Chem. Phys. 32, 25 (1992).Google Scholar
26. Chaki, T.K., Philos. Mag. Lett. 61, 5 (1990); 63, 123 (1991).Google Scholar
27. Chaki, T.K., Mater. Sci. Eng. A 190, 109 (1995).Google Scholar
28. Tabata, T. and Birnbaum, H.K., Scripta Metall. 18, 231 (1984).Google Scholar
29. Hanada, S., Ogura, T., Watanabe, S., Izumi, O., and Masumoto, T., Acta Metall. 34, 13 (1986).Google Scholar
30. Lin, H. and Pope, D.P., Acta Metall. Mater. 41, 553 (1993).Google Scholar
31. Meyers, D.E. and Ardeil, A. J., Acta. Metall. Mater. 41, 2601 (1993).Google Scholar
32. Watanabe, T., J. Phys. (Paris) 49, C5507 (1988).Google Scholar
33. Lin, H., George, E.P., and Pope, D.P., Materials Research Society Symposium Proceedings Series 364 (Boston, MA, 1995).Google Scholar