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.
Similar content being viewed by others
References
A. K. Vasudévan and J.J. Petrovic, in High Temperature Structural Silicides. edited by A. K. Vasudévan and J.J. Petrovic (Elsevier, New York, 1992), pp. 1–17.
P.J. Meschter, Metall. Trans. A23, 1763 (1992).
E. Fitzer and W. Remmele, 5th Int. Conf. on Composite Materials (The Metallurgical Society Inc., Warrendale, PA, 1985), pp. 515–530.
E. Fitzer and P. K. Schmidt, High Temp.-High Press. 3, 445 (1971).
T. C. Lu, A. G. Evans, R. J. Hecht, and R. Mehrabian, Acta Metall. 39, 1853 (1991).
P.J. Meschter, Scripta Met. et Mat. 25, 521 (1991).
D.H. Carter, “SiC Whisker-Reinforced MoSi2,” LA-11411-T (Los Alamos National Laboratory, NM, 1988).
P.J. Meschter, Scripta Met. et Mat. 25, 1065 (1991).
A. K. Bhattacharya and J.J. Petrovic, J. Am. Ceram. Soc. 75, 23 (1992).
Von E. Fitzer. “Molybdenum Disilicidc as High-Temperature Material,” Plansee Proc., 2nd Seminar, Reutte/Tyrol, 1955. pp. 56–79 (published in 1956).
J.H. Westbrook and D. L. Wood, J. Nucl. Mater. 12, 208 (1964).
T.C. Chou and T.G. Nich, Scripta Met. et Mat. 27, 19 (1993).
T. C. Chou and T. G. Nieh, Scripta Met. et Mat. 26, 1637 (1992).
D. A. Berztiss, R. R. Cerchiara, E. A. Gulbransen, F. S. Pettit, and (J.H. Meier, Mater. Sci. Eng. A155, 165 (1992).
C. G. McKamcy, P. F. Tortorelli, J.H. DeVan, and C.A. Carmichael, J. Mater. Res. 7, 2747 (1992).
T.C. Chou and T.G. Nieh. J. Mater. Res. 8. 214 (1993).
T. C. Chou and T.G. Nieh, in High-Temperature Ordered Intermetallic Alloys V, edited by 1. Baker, J.D. Whittenberger, R. Darolia, and M. H. Yoo (Mater. Res. Soc. Symp. Proc. 288, Pittsburgh. PA, 1993), p. 965.
E. Fitzer, Plansee Proc, 3rd Seminar, Reutte/Tyrol, 1958 (Springer-Verlag, Vienna, Austria, 1959), p. 175.
A. U. Scybolt and J.H. Westbrook, Report No. ASD-TDR-63-309, Part 11, 1964.
J.B. Berkowitz, P.E. Blackburn, and E.J. Felten, Trans. Metall. Soc. AIMF. 233, 1093 (1965).
R.W. Bartlett, J.W. McCamont, and P.R. Gage, J. Am. Ccram. Soc. 48, 551 (1965).
C.D. Wirkus and D. R. Wilder, J. Am. Ceram. Soc. 49, 173 (1966).
P. I. Glushko, V. I. Dorokhov, and Ye P. Nechiporenko, Phys. of Metals and Metallography (USSR) (English Transl.) 13 (6), 111 (1962).
F.J. Norton, Nature 191, 701 (1961).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Chou, T.C., Nieh, T.G. Kinetics of MoSi2 pest during low-temperature oxidation. Journal of Materials Research 8, 1605–1610 (1993). https://doi.org/10.1557/JMR.1993.1605
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1557/JMR.1993.1605