Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-17T21:21:12.794Z Has data issue: false hasContentIssue false
  • English
  • Français

The formation of discontinuous Al2O3 layers during high temperature oxidation of IrAl alloys

Published online by Cambridge University Press:  31 January 2011

T. C. Chou
T. C. Chou
Affiliation:
Research and Development, Engelhard Corporation, Edison, New Jersey 08818
Get access

Abstract

Oxidation of IrAl alloys (50-50 at.%) was conducted at 1300 and 1600°C in air for different times. Due to the outward diffusion of Al atoms and subsequent oxidation, the formation of Al2O3 is accompanied with the generation of an Ir-rich phase in the vicinity areas. The oxidation zone is separated from the bulk IrAl alloy by a phase boundary. In the oxidation zones, alternating layers of Al2O3 and Ir-rich phase are produced at 1300°C, while irregularly intertwined; Al2O3 and Ir-rich phase are produced at 1600 °C. The discontinuous formation of Al2O3 gives rise to internal oxidation of the IrAl alloys. The thickness of the Al2O3 layer is in the range of tens of micrometer, and it grows thicker as its location gets farther away from the free surface. The formation of an Al2O3/Ir-rich phase layered structure is discussed based on the diffusion kinetics of O, Al, and Ir, the chemical reactivities of Al and Ir with respect to O, and the nucleation and growth kinetics of Al2O3.

Type
Articles
Information
Journal of Materials Research , Volume 5 , Issue 2 , February 1990 , pp. 378 - 384
Copyright
Copyright © Materials Research Society 1990

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

1Liesegang, R. E., Naturw. Wschr. 11, 353 (1896).Google Scholar
2Klueh, R. L. and Mullins, W.W., Acta Metall. 17, 59 (1969).CrossRefGoogle Scholar
3Shen, Y. S., Zdanuk, E. J., and Krock, R. H., Metall. Trans. 2, 2839 (1971).CrossRefGoogle Scholar
4Osinski, K., Vriend, A.W., Bastin, G. F., and van Loo, F. J. J., Z. Metallkd. 73, 258 (1982).Google Scholar
5Patnaik, P. C., Thesis, Ph.D., McMaster University (1984).Google Scholar
6Chou, T. C., unpublished research.Google Scholar
7van Rooijen, V. A., van Royen, E.W., Vrijen, J., and Radelaar, S., Acta Metall. 23, 987 (1975).CrossRefGoogle Scholar
8Wagner, C., J. Colloid. Sci. 5, 85 (1950).CrossRefGoogle Scholar
9Ostwald, W., Z. Physik. Chem. 22, 365 (1897).Google Scholar
10Jablczynski, K., Kolloid-Z. 40, 22 (1926).CrossRefGoogle Scholar
11Lakhani, M. P. and Mathur, R. N., Kolloid-Z. 67, 59 (1934).CrossRefGoogle Scholar
12Achleussner, C. A., Kolloid-Z. 34, 338 (1924).Google Scholar
13Dee, G.T., Phys. Rev. Lett. 57, 275 (1986).CrossRefGoogle Scholar
14Lee, K. N. and Worrell, W. L. (Univ. of Pennsylvania, private discussion).Google Scholar
15Worrell, W. L., High Temperature Material Compatibility Meeting, Wright-Patterson Air Force Base, OH (Oct. 22–23, 1986).Google Scholar
16Alcock, C. B. and Hooper, G.W., Proc. Roy. Soc. A 254, 551 (1960).Google Scholar
17Darling, A.S., Int. Met. Rev., review 175, 91 (1973).CrossRefGoogle Scholar
18Reed-Hill, R. E., Physical Metallurgy Principles (Brooks/Cole Eng Div., Wadsworth Inc., California, 1973), p. 559Google Scholar