Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-27T02:19:23.207Z Has data issue: false hasContentIssue false

Phase Equilibria in the Nb-rich Nb-Ti-Si-Cr-Hf alloys

Published online by Cambridge University Press:  19 January 2011

Ying Yang
Affiliation:
CompuTherm LLC, Madison, Wisconsin 53719, USA
Bernard P. Bewlay
Affiliation:
General Electric Global Research, Schenectady, New York 12301, USA
Austin Chang
Affiliation:
University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
Get access

Abstract

Refractory Metal-Intermetallic Composites (RMICs) based on the Nb-Si system have been considered as candidates for the next-generation high temperature materials (i.e. >1200°C). Ti, Cr and Hf have been shown to have beneficial effects on the oxidation resistance and mechanical properties of Nb-Si alloys. The present study has determined phase equilibria in the Nb-rich region of the Nb-Si-Ti-Cr-Hf system via the Calphad approach. The alloying effects of Cr and Hf on the microstructure of Nb-Si-Ti alloys are understood based on isothermal sections, liquidus projections, and solidification curves that were calculated from the thermodynamic models of the Nb-Ti-Si-Cr-Hf system developed in the present study. This work provides important guidelines on the development of new Nb-Si-Ti-Cr-Hf alloys.

Type
Research Article
Copyright
Copyright © Materials Research Society 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Bewlay, B. P., Jackson, M. R., Zhao, J. C., and Subramanian, P. R., Metall Trans A, 34(10), 2043 (2003).Google Scholar
2. Bewlay, B. P., Jackson, M. R., Zhao, J. C., Subramanian, P. R., Mendiratta, M. G., and Lewandowski, J. J., MRS Bulletin, 28(9), 646 (2003).Google Scholar
3. Massalski, T. B., Okamoto, H., Binary Alloy Phase Diagrams, ASM Handbooks, Volume 3, ASM International, Ohio (1992).Google Scholar
4. Bewlay, B. P., Jackson, M. R., and Lipsitt, H. A., Metall Trans A, 27(12), 3801 (1996).Google Scholar
5. Bewlay, B. P., Jackson, M. R., and Subramanian, P. R., JOM, 51(4), 32 (1999).Google Scholar
6. Jackson, M. R., Bewlay, B. P., Rowe, R. G., Skelly, D. W., and Lipsitt, H. A., JOM, 48(1), 39 (1996).Google Scholar
7. Mendiratta, M. G., Lewandowski, J. J., and Dimiduk, D. M., Metall Trans A, 22(7), 1573 (1991).Google Scholar
8. Bewlay, B. P., Jackson, M. R., Bishop, R. R., J Phase Equilib, 19(6), 577 (1998).Google Scholar
9. Bewlay, B. P., Jackson, M. R., Lipsitt, H. A., J Phase Equilib, 18(3), 264 (1997).Google Scholar
10. Chen, S. L., Daniel, S., Zhang, F., Chang, Y. A., Yan, X. Y., Xie, F. Y., Schmid-Fetzer, R., and Oates, W. A., Calphad, 26(2), 175 (2002).Google Scholar
11. Yang, Y., Thermodynamic Database of Nb Silicide Based Alloys, CompuTherm LLC, Madison, WI 53719 (2008), http://www.computherm.com/downloads.html.Google Scholar
12. Muggianu, Y. M., Gambino, M., and Bros, J. P., Journal de Chimie Physique et de Physico-Chimie Biologique, 72(1), 83 (1975).Google Scholar
13. Yang, Y., Bewlay, B. P., Chen, S.-L., Jackson, M. R., Chang, Y. A.,MRS Proceedings, 1128. Paper #: 1128-U05-42, (2008).Google Scholar
14. Yang, Y., Bewlay, B. P., Chang, Y.A., J Phase Equilib Diff, 28(1), 107 (2007).Google Scholar
15. Scheil, E., Z Metallkd, 34, 242 (1942).Google Scholar