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An electron microscopy study of the precipitation of rhenium in the B2 nickel aluminide

  • D.C. Van Aken (a1), D.P. Mason (a1), S.G. Malhotra (a1) and J.G. Webber (a1)

Abstract

Precipitation of rhenium in β–NiAl was studied by analytical and high resolution electron microscopy. Extended solid solutions were created by solidification processing, and the precipitation and hardening behavior were studied. Evidence suggests that rhenium is initially precipitated as disks parallel to {100} of β-NiAl. Subsequent growth produces either a rod morphology or a pair of twin-related rods that form the shape of a butterfly. The twin plane of the butterfly is {1011} and this plane is nearly parallel to {110} of β–NiAl. A twinning transformation given by K1 = {1011}, K2 = {1013}, η1 = 〈1012 〉, and η2 = 〈3032〉 was determined for the butterfly-shaped particles. All of the precipitates exhibited an orientation relationship consisting of parallel close-packed planes and directions, i.e., (101//(0001) and [111]//[1210]. Performing the twinning transformation on a rhenium precipitate produces a variant rather than a new orientation relationship. After elevated temperature aging, a rod morphology was observed with the rod axes aligned parallel with either 〈121〉 or 〈131〉 of the β–NiAl matrix. A total of 24 different variants are possible based upon the observed orientation relationship and the two observed growth directions.

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1Darolia, R., JOM 43, 44 (1991).
2Sims, C. T., ASM Metals Handbook, 8th ed. (American Society for Metals, Metals Park, OH, 1961), Vol. 1, p. 1220.
3Raffo, P. L. and Witzke, W. R., Trans. AIME 245, 889 (1956).
4Mason, D. P., Van Aken, D. C., and Webber, J. G., in Intermetallic Matrix Composites, edited by Anton, D. L., Martin, P. L., Miracle, D. B., and McMeeking, R. (Mater. Res. Soc. Symp. Proc. 194, Pittsburgh, PA, 1990), pp. 341348.
5Webber, J. G. and Van Aken, D. C., Scripta Metall. 23, 193 (1989).
6Vedula, K., Pathare, V., Aslanidis, I., and Titran, R. H., in High-Temperature Ordered Intermetallic Alloys, edited by Koch, C. C., Liu, C. T., and Stoloff, N. S. (Mater. Res. Soc. Symp. Proc. 39, Pittsburgh, PA, 1985), pp. 411421.
7Mason, D. P., Van Aken, D. C., Noebe, R. D., Locci, I. E., and King, K. L., in High Temperature Ordered Intermetallic Alloys IV, edited by Johnson, L.A., Pope, D. P., and Stiegler, J. O. (Mater Res. Soc. Symp. Proc. 213, Pittsburgh, PA, 1991), pp. 10331038.
8Laves, F., Theory of Alloy Phases (American Society for Metals, Metals Park, OH, 1956), pp. 124198.
9Darolia, R., Lahrman, D. F., Field, R. D., and Freeman, A. J., in High Temperature Ordered Intermetallic Alloys III, edited by Liu, C.T., Taub, A. I., Stoloff, N. S., and Koch, C. C. (Mater. Res. Soc. Symp. Proc. 133, Pittsburgh, PA, 1989), pp. 113118.
10Noebe, R. D., Bowman, R. R., Cullers, C. L., and Raj, S. V., 3rd Annual HITEMP Review–1990, NASA CP-10051 (1990), pp. 2021.
11Wasilewski, R. J., Trans. Metall. Soc. AIME 236, 455 (1966).
12Cahn, J. W. and Kalonji, G., Solid-State Phase Transformations, edited by Aaronson, H. I., Laughlin, D. E., Sekerka, R. F., and Wayman, C. M. (The Metallurgical Society, Inc., 1982), pp. 314.

An electron microscopy study of the precipitation of rhenium in the B2 nickel aluminide

  • D.C. Van Aken (a1), D.P. Mason (a1), S.G. Malhotra (a1) and J.G. Webber (a1)

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