Hostname: page-component-5c6d5d7d68-wbk2r Total loading time: 0 Render date: 2024-08-08T10:42:09.725Z Has data issue: false hasContentIssue false
  • English
  • Français

Kinetics of MoSi2 pest during low-temperature oxidation

Published online by Cambridge University Press:  31 January 2011

T.C. Chou  and
T.G. Nieh
T.C. Chou
Affiliation:
Lockhead Research and Development Division, 0/93-10, B/204, 3251 Hanover Street, Palo Alto, California 94304-1191
T.G. Nieh
Affiliation:
Lawrence Livermore National Laboratory, P.O. Box 808, L-350, Livermore, California 94550
Get access

Abstract

The kinetics of MoSi2 pest, caused by oxidation in air, has been studied. Experimental results indicated that pest disintegration occurred at temperatures between 375 and 500 °C. The volumes of test samples increased with oxidation duration. Analysis of change in sample volume versus oxidation duration revealed that the pest disintegration consisted of two stages, namely nucleation (or incubation) and growth. The onset of the growth stage depended on the test temperature. More importantly, changes in sample volume were found to obey a linear relationship with time during the growth stage. Equations were formulated to demonstrate that the growth kinetics of pest disintegration was proportional to the rates of change in sample volume. The rates of volume change during MoSi2 pest were calculated to be 4.9 × 10−6, 2.8 × 10−5, 3.7 × 10−5, and 5.4 × 10−5 cm3/s at 375, 400, 425, and 450 °C, respectively; the growth kinetics increased with oxidation temperature. The activation energy for the growth stage of pest disintegration was determined to be 27.6 kcal/mole, which agrees well with the activation energy for the low-temperature oxidation of MoSi2.

Type
Articles
Information
Journal of Materials Research , Volume 8 , Issue 7 , July 1993 , pp. 1605 - 1610
Copyright
Copyright © Materials Research Society 1993

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

1Vasudevan, A. K. and Petrovic, J. J. in High Temperature Structural Silicides, edited by Vasudevan, A. K. and Petrovic, J. J. (Elsevier, New York, 1992),pp. 1–17.Google Scholar
2Meschter, P.J.Metall. Trans. A23, 1763 (1992).Google Scholar
3Fitzer, E. and Remmele, W.5th Int. Conf. on Composite Materials (The Metallurgical Society Inc., Warrendale, PA, 1985), pp. 515–530.Google Scholar
4Fitzer, E. and Schmidt, F.K.High Temp High Press. 3, 445 (1971).Google Scholar
5Lu, T. C.Evans, A. G.Hecht, R. J. and Mehrabian, R.Act a Metall. 39, 1853 (1991).Google Scholar
6Meschter, P. J.Script a Met et Mat. 25, 521 (1991).Google Scholar
7Carter, D.H. "SiC Whisker-Reinforced MoSi2,” LA-11411-T (Los Alamos National Laboratory, NM, 1988).Google Scholar
8Meschter, P.J.Script a Met et Mat. 25, 1065 (1991).Google Scholar
9Bhattacharya, A. K. and Petrovic, J. J.J. Am. Ceram. Soc. 75, 23 (1992).Google Scholar
10Fitzer, Von E. “Molybdenum Disilicide as High-Temperature Material,” Plansee Proa, 2nd Seminar, Reutte/Tyrol, 1955, pp. 56–79 (published in 1956).Google Scholar
11Westbrook, J.H. and Wood, D.L.J. Nucl. Mater. 12, 208 (1964).Google Scholar
12Chou, T.C. and Nieh, T.G.Script a Met et Mat. 27, 19 (1993).Google Scholar
13Chou, T. C. and Nieh, T. G.Script a Met et Mat. 26, 1637 (1992).Google Scholar
14Berztiss, D. A.Cerchiara, R. R.Gulbransen, E. A.Pettit, F. S. and Meier, G. H.Mater. Sci. Eng. A155, 165 (1992).Google Scholar
15McKamey, C.G.Tortorelli, P.F.DeVan, J.H. and Carmichael, C.A., J. Mater. Res. 7, 2747 (1992).Google Scholar
16Chou, T.C. and Nieh, T.G.J. Mater. Res. 8, 214 (1993).Google Scholar
17Chou, T.C. and Nieh, T.G. in High-Temperature Ordered Intermetallic Alloys V, edited by Baker, I.Whittenberger, J. D.Darolia, R. and Yoo, M.H. (Mater. Res.Soc. Symp. Proc. 288, Pittsburgh, PA, 1993), p. 965.Google Scholar
18Fitzer, E.Plansee Proc, 3r d Seminar, Reutte/Tyrol, 1958 (Springer-Verlag, Vienna, Austria, 1959), p. 175.Google Scholar
19Seybolt, A. U. and Westbrook, J. H. Report No. ASD-TDR-63-309, Part II, 1964.Google Scholar
20Berkowitz, J. B.Blackburn, P. E. and Felten, E. J.Trans. Metall. Soc. AIME 233, 1093 (1965).Google Scholar
21Bartlett, R.W.McCamont, J.W. and Gage, P.R.J. Am. Ceram. Soc. 48, 551 (1965).Google Scholar
22Wirkus, C.D. and Wilder, D.R.J. Am. Ceram. Soc. 49, 173 (1966).Google Scholar
23Glushko, P. I.Dorokhov, V. I. and Nechiporenko, Ye P.Phys. of Metals and Metallography (USSR) (English Transl.) 13 (6), 111 (1962).Google Scholar
24Norton, F.J.Nature 191, 701 (1961).Google Scholar