Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-20T08:31:07.921Z Has data issue: false hasContentIssue false
  • English
  • Français

Influence of solidification rate on precipitation and microstructure of directional solidification IN792 + Hf superalloy

Published online by Cambridge University Press:  31 January 2011

W. R. Sun ,
Z. Q. Hu ,
J. H. Lee ,
S. M. Ceo  and
S. J. Choe
W. R. Sun
Affiliation:
Department of Superalloys and Special Castings, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110015, People's Republic of China
Z. Q. Hu
Affiliation:
State Key Laboratory of Rapidly Solidified Nonequilibrium Alloy, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110015, People's Republic of China
J. H. Lee
Affiliation:
Department of Metallurgy and Materials Science, Changwon National University, 9 Sarim-Dong, Changwon, Kyungnam, 641–773, Korea
S. M. Ceo
Affiliation:
High Temperature Materials Laboratory, Korea Institute of Machinery and Materials, 66 Sangnam Dong, Changwon, Kyungnam, 641–010, Korea
S. J. Choe
Affiliation:
High Temperature Materials Laboratory, Korea Institute of Machinery and Materials, 66 Sangnam Dong, Changwon, Kyungnam, 641–010, Korea
Get access

Abstract

The effect of solidification rate on the precipitation and microstructure of directional solidification IN792 + Hf alloy was studied. The solidification sequence and the initial precipitation temperature of different phases were determined by the observation of the quenched microstructure combined with the differential thermal analysis measurement. The script carbide was turned into faceted carbide with the drop of solidification rate. It was concluded by microstructure analysis that the faceted carbide was pushed by the γ solid front before it was captured. The incorporation of γ phase into the faceted carbide was due to the dendrite growth of the carbide toward one point and the mergence of the dendrites. Some long carbide bars were formed along the grain boundaries by continual reaction of eutectic (γ + MC carbide) at a solidification rate of 0.5 μm/s. Two zones, the γ′ forming elements enriched zone and depleted zone, were found in the residual liquid area. Eutectic γ/γ′ nucleated in the γ′ forming elements enriched zone. The η-phase precipitation was controlled by the ratio of (Ti + Hf + Ta + W)/Al in the residual liquid. The growth of eutectic γ/γ′ increased the ratio and induced the η-phase precipitation. A lower solidification rate decreased the ratio by sufficient diffusion and hence efficiently suppressed the η-phase precipitation.

Type
Articles
Information
Journal of Materials Research , Volume 14 , Issue 10 , October 1999 , pp. 3873 - 3881
Copyright
Copyright © Materials Research Society 1999

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.McLean, M., Directionally Solidified Materials for High Temperature Service (Metals Society, London, 1983), pp. 49, 107.Google Scholar
2.Sims, C.T., Stoloff, N.S., and Hagel, W.C., Superalloys II (John Wiley & Sons, New York, 1987), pp. 97, 118.Google Scholar
3.Pollock, T.M. and Murphy, W.H., Metall. Mater. Trans. A 27, 1081 (1996).Google Scholar
4.Lecomte-Beckers, J., Metall. Mater. Trans. A 19, 2333 (1988).CrossRefGoogle Scholar
5.Sellamuthu, R., Brody, H.D., and Giamei, A.F., Metall. Mater. Trans. B 17, 347 (1986).Google Scholar
6.Zhu, H.Q., Hu, Z.Q., Zhu, Y.X., Guo, S.R., Guan, H.R., Shi, C.X., Morinaga, M., and Murata, Y., Metall. Mater. Trans. B 26, 831 (1995).Google Scholar
7.Wills, V.A. and McCartney, D.G., Mater. Sci. Eng. 145A, 223 (1991).Google Scholar
8.Gell, M. and Leverant, G.R., Trans. Metall. Soc. AIME 242, 1869 (1968).Google Scholar
9.Mitchell, A., Schmalz, A.J., Schvezov, C., and Cockcroft, S.L., in Superalloys 718, 625, 706 and Various Derivatives, edited by Loria, E.A. (The Minerals, Metals & Materials Society, Warrendale, PA, 1994), p. 65.CrossRefGoogle Scholar
10.Lin, L., Hengzhi, F., and Zhengxing, S., Scr. Metall. Mater. 50, 587 (1994).Google Scholar
11.Fernandez, R., Lecomte, J.C., and Kattamis, Z., Metall. Mater. Trans. A 9, 1381 (1978).CrossRefGoogle Scholar
12.Fegan, S.C., Kattamis, T.Z., and Morral, J.E., J. Mater. Sci. 10, 1266 (1975).Google Scholar
13.Chuanqi, C., Qijuan, L., Changxin, W., Shifan, T., and Radavich, J.F., Superalloys 1996, edited by Kissinger, R.D., Deye, D.J., Anton, D.L., Cetel, A.D., Nathal, M.V., Pollock, T.M. and Woodford, D.A. (Minerals, Metals, and Materials Society, Warrendale, PA, 1996), p. 507.Google Scholar
14.Kotval, P.S., Venables, J.D., and Calder, R.W., Metall. Mater. Trans. A 3, 453 (1972).Google Scholar
15.Bouse, G.K., Superalloys 1996, edited by Kissinger, R.D., Deye, D.J., Anton, D.L., Cetel, A.D., Nathal, M.V., Pollock, T.M., and Woodford, D.A. (Minerals, Metals, and Materials Society, Warrendale, PA, 1996), p. 163.Google Scholar
16.Sponseller, D.L., Superalloys 1996, edited by Kissinger, R.D., Deye, D.J., Anton, D.L., Cetel, A.D., Nathal, M.V., Pollock, T.M., and Woodford, D.A. (Minerals, Metals, and Materials Society, Warrendale, PA, 1996), p. 259.Google Scholar
17.Bhambri, A.K., Kattamis, T.Z., and Morral, J.E., Metall. Mater. Trans. B 6, 523 (1975).CrossRefGoogle Scholar
18.Uhlmann, D.R. and Chalmers, B., J. Appl. Phys. 35, 2986 (1964).CrossRefGoogle Scholar