Abstract
By using high temperature optical microscopy, oxidation behaviors of poly-and single crystalline NbSi2 were observed in-situ at 1023 K. The effects of micro-cracks, porosity and grain boundary on the oxidation behavior of NbSi2 have been studied. The results indicate that new cracks initiate and extend from the pre-existing cracking areas in the arc-melted poly-crystalline specimen, leading to fragmentation after 220 min at 1023 K. However, although pores and grain boundary are the preferential oxidation site, they do not directly lead to fragmentation during oxidation, indicating that the pre-existing cracks in specimen are the key reason to pesting. The oxidation kinetics of the studied NbSi2 specimens corresponds well with the in-situ observation.
Similar content being viewed by others
References
Fitzer, V. E., Benesovsky, F., Molybdenum disilicides as high-temperature materials, in Plansee Proc. 2nd Seminar Reutte/Tyrol, Vienna: Springer, 1955, 56–79.
Berztiss, D. A., Cerchiara, R. R., Cerehiara, E. A. et al., Oxidation of MoSi2 and comparison with other silicide materials, Materials Science and Engineering, 1992, A155: 165–181.
Schlichting, J., Molybdenum disilicide as a component in modern high-temperature solid solutions, High Temperatuer and High Pressure, 1978, 10: 241–269.
Maruyama, T., Yanagihara, K., High temperature oxidation and pesting of Mo(Si, Al)2, Materials Science and Engineering A, 1997, 239–240: 828–841.
Rausch, J. J., ARF-2981-4, Armour Research Foundation NSA, 1961, 15–31171.
Pitman, S. H., Tsakiropoulos, P., Study of the microstructure and oxidation of NbSi2 base alloys, in High-temperature ordered Intermetallic Alloys VI, Materials Research Symposium Proceeding, Vol. 364 (ed. Horton, J.), Boston: Material Research Society, 1995, 1321.
Murakami, T., Sasaki, S., Ichikawa, K. et al., Microstructure, mechanical properties and oxidation behavior of Nb-Si-Al and Nb-Si-N powder compacts prepared by spark plasma sintering, Intermetallics, 2001, 9: 621.
Mckamey, C. G., Tortorelli, P. F., DeVan, J. H. et al., Study of pest oxidation in polycrystalline MoSi2, Journal of Material Research, 1992, 7(10): 2747–2755.
Chou, T. C., Nieh, T. G., Mechanism of MoSi2 pest during low temperature oxidation, Journal of Material Research, 1993, 8(1): 214–226.
Boccaccini, A. R., Hamann, B., In situ high-temperature optical microscopy, Journal of Material Science, 1999, 34: 5419.
Miller, R. J., Gleeson, H. F., Computer interfaced high-stability temperature controller and heating stage for optical microscopy, Meas. Sci. Technol., 1994, 5: 904.
Hu, J., Yao, X., Rao, Q. L., Real-time observation of the melting process of YBCO thin film on MgO substrate, Journal of Physics: Condensed Matter, 2003, 15: 7149.
Tick, P. A., Lu, K. E., Mitachi, S. et al., Hot stage optical microscopy studies of crystallization in fluoride glass melts, Journal of Non-Crystal Solids, 1992, 140: 279.
Boccaccini, A. R., Sintering of glass matrix composites containing Al2O3 platelet inclusions, Journal of Material Science, 1994, 29: 4273.
Gale, W. F., Fergus, J. W., Ingram, W. M. et al., Wettability of NiAl by a liquid Ni-Si-B alloy, Journal of Material Science, 1997, 32: 4931.
Zhang, F., Zhang, L. T., Wu, J. S., Acta Metallurgica Sinica, 2005, 6: 645–648.
Li, M. S., High Temperature Corrosion of Metals, Beijng: Metallurgical Industry Press, 2001, 36–37.
Hagihara, K., Maeda, S., Nakano, T. et al., Indentation fracture behavior of (Mo0.85Nb0.15)Si2 crystals with C40 single-phase and MoSi2(C11b)/NbSi2(C40) duplex-phase with oriented lamellae, Science and Technology of Advanced Materials, 2004, 5(1–2): 11.
Kurokawa, K., Houzumi, H., Saeki, I. et al., Low temperature oxidation of fully dense and porous MoSi2, Materials Science and Engineering, 1999, A261: 292–299.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Zhang, F., Zhang, L., Shan, A. et al. Oxidation kinetics and high temperature in-situ observation of the oxidation behaviour of NbSi2 at 1023 K. SCI CHINA SER E 49, 147–155 (2006). https://doi.org/10.1007/s11431-006-0147-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11431-006-0147-x