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Ductility Enhancement Via Microstructural Control in Cr Modified Ni3AAl Single Crystal

Published online by Cambridge University Press:  01 January 1992

S.E. Hsu ,
Y.P. Wu ,
T.S. Lee  and
S.C. Yang
S.E. Hsu
Affiliation:
Materials Research and Development Center, Chung ShanInstitute of Science and Technology, Lung-Tan, Taiwan, R.O.C.
Y.P. Wu
Affiliation:
Materials Research and Development Center, Chung ShanInstitute of Science and Technology, Lung-Tan, Taiwan, R.O.C.
T.S. Lee
Affiliation:
Materials Research and Development Center, Chung ShanInstitute of Science and Technology, Lung-Tan, Taiwan, R.O.C.
S.C. Yang
Affiliation:
Materials Research and Development Center, Chung ShanInstitute of Science and Technology, Lung-Tan, Taiwan, R.O.C.
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Abstract

An attempt to improve the ductility in Cr modified Ni3Al alloys is made by means of microstructural control. In order to select an alloy composition such that it locates in the γ ' single phase region at 1000 °C and in the γ + γ ' two-phase region at 1200 °C of the Ni-Al-Cr ternary phase diagram, we first calculated γ and γ ' phase boundaries, using the Cluster Variation Method. Single crystal specimens with desired composition of Ni-19.5Al-7.5Cr at% were grown and homogenized at the above two temperatures for 72 hours and the mechanical properties were tested at room temperature. It is found that the elongation of specimen homogenized at 1200 °C is almost twice as large as that of one homogenized at 1000 °C. The theoretically predicted microstructures and the γ precipitates are also confirmed by optical, SEM micrographs and EDS analysis. It is concluded that a small amount of disordered γ phase precipitates in the γ ' matrix can drastically enhance the tensile ductility of Ni3Al (Ll2)-base alloys

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 288: Symposium L – High-Temperature Ordered Intermetallic Alloys V , 1992 , 617
Copyright
Copyright © Materials Research Society 1995

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References

REFERENCES

1. Hsu, S.E., Tong, C.H., Lee, T.S. and Liu, T.S., in High-Temperature Ordered Intermetallic Alloys III, MRS symposia, ed. by Liu, C.T., Taub, A.I., Stoloff, N.S. and Koch, C.C., Vol 133, pp. 275–280 (1989).Google Scholar
2. Wu, Y.P., Tso, N.C., Sanchez, J.M. and Tien, J.K., Acta Metall. 37 , 2835 (1989).Google Scholar
3. Wu, Y.P., Lin, Y.L. and Hsu, S.E., in Proc. of The 1992 Annual Conf. of The Chinese Soc. for Mat. Sci., pp. 98–99 (1992).Google Scholar
4. Inoue, A., Tomiku, H. and Masumoto, T., Met. Trans. A 14 , 1367 (1983).Google Scholar
5. Kikuchi, R., Acta Metall. 25, 195 (1977).Google Scholar
6. Sigili, C. and Sanchez, J.M., Acta Metall. 33 , 1097 (1985).Google Scholar
7. Cahn, R.W., Siemers, P.A., Gieger, J.E. and Bardhan, P., Acta Metall. 35, 2737 (1987).Google Scholar
8. Cahn, R.W., Siemers, P.A. and Hall, E.L., Acta Metall. 35, 2753 (1987).Google Scholar