Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-20T07:18:52.910Z Has data issue: false hasContentIssue false
  • English
  • Français

Lattice Defects Affecting Moisture-Induced Embrittlement of Ni-based L12 Ordered Intermetallics

Published online by Cambridge University Press:  15 February 2011

T. Takasugi  and
S. Hanada
T. Takasugi
Affiliation:
Institute for Materials Research, Tohoku University, Katahira 2–1–1, Aoba-ku, Sendai, 98077, Japan
S. Hanada
Affiliation:
Institute for Materials Research, Tohoku University, Katahira 2–1–1, Aoba-ku, Sendai, 98077, Japan
Get access

Abstract

Moisture-induced embrittlement of Ll2 alloys (such as Ni3(Si,Ti) and Ni3AI) is observed by tensile test and SEM fractography. A variety of microstructures were prepared by selecting pre-deformation and heat treatment conditions. It is shown that tensile ductility and the associated fractography depend on structure as well as test atmosphere. Well-annealed specimens are susceptible to moisture-induced embrittlement while pre-deformed specimens are resistive to moisture-induced embrittlement. Also, this embrittlement is generally sensitive to the heat treatment scheme preceded by the pre-deformation. Results indicate that the embrittlement occurs when hydrogen is enriched on grain boundaries. On the other hand, the embrittlement can be suppressed when hydrogen is trapped at lattice defects such as dislocations and vacancies. These results are discussed in association with the kinetics of hydrogen in the pre-deformed microstructure.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 460: Symposium Z – High-Temperature Ordered Intermetallic Alloys VII , 1996 , 587
Copyright
Copyright © Materials Research Society 1997

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

1. Takasugi, T. and Izumi, O., Acta metali, 34, 607 (1986).Google Scholar
2. Liu, C. T. and Oliver, W. C., Scripta metall. et mater., 25, 1933 (1991).Google Scholar
3. Takasugi, T., Suenaga, H. and Izumi, O., J. of Mater. Sci., 26, 1179 (1991).Google Scholar
4. Liu, C. T., Scripta metall et mater., 27, 25 (1992).Google Scholar
5. Takasugi, T. and Hanada, S., Acta metall. et mater., 42, 3527 (1994).Google Scholar
6. Ma, C. L., Takasugi, T. and Hanada, S., Scripta materialia, 34, 1131 (1996).Google Scholar
7. Takasugi, T., Critical Issues in the Development of High Temperature Structural Materials, edited by Stoloff, N., Duquette, D. J. and Giamei, A. F., The Minerals, Metals and Materials Society, Warrendale, PA, p. 399, (1993).Google Scholar
8. Liu, C. T., 6th Int. Symp. Intermetallic Compounds - Structure and Mechanical Properties, edited by Izumi, O., JIM, p. 703, (1991).Google Scholar
9. Yang, L. and McLellan, R. B., Acta metali, mater., 42, 3993 (1994).Google Scholar
10. Yang, L. and McLellan, R. B., Scripta metall. mater., 32, 779 (1994).Google Scholar
ll. Kimura, A., Izumi, H., Misawa, T. and Saitoh, H., Mater. Trans. JIM, 35, 879 (1994).Google Scholar
12. Pope, D. P. and Ezz, S. S., International Metals Reviews, 29, 123 (1984).Google Scholar