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Phase Stability in Processing and Microstructure Control in High Temperature Mo-Si-B Alloys

Published online by Cambridge University Press:  21 March 2011

J.H. Perepezko ,
R. Sakidja  and
S. Kim
J.H. Perepezko
Affiliation:
Department of Materials Science and Engineering, University of Wisconsin-Madison, 1509 University Ave, Madison, WI 53706, USA
R. Sakidja
Affiliation:
Department of Materials Science and Engineering, University of Wisconsin-Madison, 1509 University Ave, Madison, WI 53706, USA
S. Kim
Affiliation:
Department of Materials Science and Engineering, University of Wisconsin-Madison, 1509 University Ave, Madison, WI 53706, USA
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Abstract

For applications at ultrahigh temperatures the multiphase microstructural options that can be developed in the Mo-Si-B system have demonstrated an effective and attractive balance of essential characteristics. The coexistence of the high melting point (>2100°C) ternary intermetallic Mo5SiB2 (T2) phase with Mo provides a useful option for in-situ toughening. A further enhancement is available from a precipitation reaction of Mo within the T2 phase that develops due to the temperature dependence of the solubility behavior of the T2 phase. However, direct access to Mo+T2 microstructures is not possible in ingot castings due to solidification segregation reactions that yield nonequilibrium boride and silicide phases with sluggish dissolution. Alternate routes involving rapid solidification of powders are effective in suppressing the segregation induced phases. The processing and microstructure options can also be augmented by selected refractory metal substitutional alloying, such as the incorporation of Nb, that alters the solubility of the T2 phase and the relative phase stability to yield solidification of two phase refractory solid solution + T2 structures directly. The observed alloying trends highlight the role of atomic size in influencing the relative stability of the T2 phase. A key component of the overall microstructural control and long term microstructural stability is determined by the kinetics of diffusional processes. The analysis of selected diffusion couples involving binary boride and silicide phases has been used to assess the relative diffusivities in the T2 phase and coexisting phases over the range of solubility and to provide a basis for the examination of the kinetics of reactions involved in coatings and oxidation.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 646 , 2000 , N4.5.1
Copyright
Copyright © Materials Research Society 2001

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References

REFERENCES

[1] Stoloff, N. A., in Superalloy II, edited by Sims, C. T. (John Wiley, New York, 1987), p. 61.Google Scholar
[2] Ross, E. R. and Sims, C. T.,in Superalloy II, edited by (John Wiley, New York, 1987), p. 97.Google Scholar
[3] Dyson, B. F. and McLean, M., JISI Int., 30, 802 (1990).Google Scholar
[4] Diminuk, D. M., Miracle, D. B. and Ward, C. H., Mater. Sci. and Tech., 8, 367 (1992).10.1179/mst.1992.8.4.367Google Scholar
[5] George, E. P., Yamaguchi, M., Kumar, K. S. and Liu, C. T., Annu. Rev. Mater. Sci., 24, 409 (1994).10.1146/annurev.ms.24.080194.002205Google Scholar
[6] Kim, Y. W. and Diminuk, D. M., J. Metals, 43, 40 (1991).Google Scholar
[7] Meier, G. H. and Pettit, F. S., Mater. Sci and Tech., 8, 331 (1992).10.1179/mst.1992.8.4.331Google Scholar
[8] Naka, S., Thomas, M. and Khan, T., Mater. Sci. and Tech., 8, 291 (1992).10.1179/mst.1992.8.4.291Google Scholar
[9] Yang, R., Saulders, N., Leake, J. A. and Cahn, R. W., Acta Metall. Mater., 40, 1553 (1992).10.1016/0956-7151(92)90098-YGoogle Scholar
[10] Yang, R., Leake, J. A., and Cahn, R. W., Mater. Sci. Engr. A, A152, 227 (1992).10.1016/0921-5093(92)90071-8Google Scholar
[11] Fleischer, R. L., J. Mater. Sci., 22, 2281 (1987).10.1007/BF01082105Google Scholar
[12] Birks, N. and Meier, G. H., Introduction to High Temperature Oxidation of Metals, (E.Arnolds, London, 1983) p. 54.Google Scholar
[13] Vasudevan, A. K. and Petrovic, J. J., Mater. Sci. and Eng. A, A155, 1 (1992).10.1016/0921-5093(92)90308-NGoogle Scholar
[14] Shah, D. M., Berczik, D., Anton, D. and Hect, R., Mater. Sci. Eng. A, A155, 45 (1992).10.1016/0921-5093(92)90311-NGoogle Scholar
[15] Alman, D. E. and Stoloff, N. S., Mat. Res. Soc. Symp. Proc., 322, 255 (1994).10.1557/PROC-322-255Google Scholar
[16] Boettinger, W. J., Perepezko, J. H. and Frankwicz, P. S., Mater. Sci. Eng. A, A155, 33 (1992).10.1016/0921-5093(92)90310-WGoogle Scholar
[17] Perepezko, J. H., Nunes, C. A., Yi, S. H., and Thoma, D. J., in High-Temperature Ordered Intermetallic Alloys VII, edited by Koch, C.C., Liu, C. T., Stoloff, N. S. and Wanner, A.,(Mater. Res. Soc. Proc. 460, Pittsburgh, PA, 1997) pp. 1–14.Google Scholar
[18] Nunes, C. A., Sakidja, R. and Perepezko, J. H., in Structural Intermetallics 1997, edited by Nathal, M. V., Darolia, R., Liu, C. T., Martin, P. L., Miracle, D. B., Wagner, R. and Yamaguchi, M.(TMS, Warrendale, PA, 1997) p. 831.Google Scholar
[19] Sakidja, R., Sieber, H., and Perepezko, J. H., in Molybdenum and Molybdenum Alloys, edited by Crowson, A., Chen, E. S., Shield, J.A and Subramanian, P. R. (TMS, Warrendale, PA, 1998) pp. 99–110.Google Scholar
[20] Sakidja, R., Sieber, H., Perepezko, J. H., Philosophical Magazine Letters, 79 (6), 351–357 (1999).10.1080/095008399177192Google Scholar
[21] Schneibel, J. H., Liu, C. T., Easton, D. S., and Carmichael, C. A., Mat. Sci. & Eng. A, A1–2, 78–83 (1999).10.1016/S0921-5093(98)01051-XGoogle Scholar
[22] Schneibel, J. H., Liu, C. T., Heatherly, L., and Kramer, M. J., Scripta Materialia, 38 (7), 1169–76 (1998).10.1016/S1359-6462(97)00558-7Google Scholar
[23] Thom, A. J., Meyer, M. K., Akinc, M. and Kim, Y., in Processing and Fabrication of Advanced Materials for High Temperature Applications III, edited by Srivitsan, T. S. and Ravi, V.A., (TMS, Warrendale, PA, 1993) pp. 413.Google Scholar
[24] Nunes, C. A., Sakidja, R., Dong, Z. and Perepezko, J. H., Intermetallics, 8 (4), 327–337 (2000).Google Scholar
[25] Sakidja, R., Wilde, G., Sieber, H. and Perepezko, J. H., in High-Temperature Ordered Intermetallic Alloys VIII, edited by George, E. P., Yamaguchi, M. and Mills, M.J., (Mater. Res. Soc. Proc. 522, Pittsburgh, PA, 1999) pp. 1–6.Google Scholar
[26] Kim, S., Sakidja, R., Dong, Z., Perepezko, J. H. and Kim, Y. W., this symposium.Google Scholar
[27] Kim, S. and Perepezko, J. H., to be publishedGoogle Scholar
[28] Barnett, R. W. and Larssen, P. A., Trans AIME, 230, 1528 (1964).Google Scholar
[29] Tortorici, P. C. and Dayananda, M. A., Mater. Sci. & Eng. A, A261, 64–77 (1999).Google Scholar
[30] Franceschi, E. A. and Ricaldone, F., Revue de Chimie minerale, 21, 202–220 (1984).Google Scholar
[31] Kuz'ma, Y. B., Poroshkovaya Metallurgiya [Soviet Powder Metallurgy and Metal Ceramics, 10 (4), 298 (1971)].Google Scholar