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Incipient Melting and Oxidation of Grain Boundary in a Two-Phase Ni3Al Alloy Containing Zr

Published online by Cambridge University Press:  22 February 2011

Huaxin Li  and
T.K. Chaki
Huaxin Li
Affiliation:
Associated Western Universities, N.W. Division, C/O. Battelle PNL, Mail Stop P8–15, Richland, WA 99352
T.K. Chaki
Affiliation:
State University of New York, Department of Mechanical and Aerospace Engineering, Buffalo, NY 14260
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Abstract

Incipient melting and oxidation of grain boundaries at elevated temperatures have been investigated in the investment cast billet of a two-phase (γ + γ′) nickel aluminide alloy (Ni74.48Al16.98Cr8.02Zr0.51B0.10), designated as IC-218. Due to enrichment of Zr, which can form eutectic alloys with Ni, the inter-dendritic regions and grain boundaries melted incipiently at 1150°C. During quenching the molten layers often opened up producing cracks at the boundaries. Annealing at 1200°C in air for 570 min produced elongated ZrO2 precipitates at the grain boundaries. There was Zr depletion inside the grains in the vicinity of the precipitates. Such precipitates were scarcely observed in the specimens annealed in air at 1100°C for 23 h. Thus, the molten Ni-Zr alloy at the boundaries promoted internal oxidation.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 364: Symposium L – High-Temperature Ordered Intermetallic Alloys–VI , 1994 , 993
Copyright
Copyright © Materials Research Society 1995

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References

1. Verhoeven, J.D., Lee, J.H., Laabs, F.C., and Jones, L.L., J. Phase Equilibria 12, 15 (1991).Google Scholar
2. Liu, C.T., White, C.L., and Horton, J.A., Acta Metall. 33, 213 (1985).Google Scholar
3. Aoki, K. and Izumi, O., J. Japan Inst. Metals 43, 1190 (1979).Google Scholar
4. Chaki, T.K., Philos. Mag. Lett. 61, 5 (1990); 63, 123 (1991).Google Scholar
5. Chaki, T.K., Mater. Sci. Eng. A 190, 109 (1995).Google Scholar
6. Sikka, V.K., Mavity, J.T., and Anderson, K., Mater. Sci. Eng. A 153, 712 (1992).Google Scholar
7. Sikka, V.K., Mater. Manufact. Processes 4, 1 (1989).Google Scholar
8. Massalski, T.B., Binary Alloy Phase Diagrams, Vol. 3, 2nd ed. (ASM International, Ohio, 1990), p. 2890.Google Scholar
9. Liu, C.T., Sikka, V.K., Horton, J.A., and Lee, E.H., Report ORNL-6483 (Oak Ridge National Laboratory, Tennessee, 1988).Google Scholar
10. Zhang, J., Tang, Y., Zhang, J., Zhang, Z., Yu, Y., Li, Y., and Hu, Z., Acta Metall. Sinica 3, 149 (1990).Google Scholar
11. Chen, G.H. and Chen, C., Scripta Metall. Mater. 27, 121 (1992).Google Scholar
12. Chuang, T.H. and Pan, Y.C., Metall. Trans. A 23, 1187 (1992).Google Scholar
13. Li, H. and Chaki, T.K., Mater. Sci. Eng. A 183, 131 (1994); (1995) in press.Google Scholar
14. Meijering, J.L. in Advances in Materials Research, Vol. 5, edited by Herman, H. (Wiley-Interscience, New York, 1971) pp. 1–81.Google Scholar
15. Taylor, A. and Floyd, R.W., J. Inst. Metals 81, 451 (1952).Google Scholar
16. Li, H. and Chaki, T.K. in Processing and Fabrication of Advanced Materials for High Temperature Applications - II, edited by Ravi, V.A. and Srivatsan, T.S. (The Minerals, Metals and Materials Society, PA, 1993) pp. 563–591.Google Scholar
17. Pepe, J.J. and Savage, W.F., Weld J. 46, 411-s (1967).Google Scholar