Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-20T02:48:47.076Z Has data issue: false hasContentIssue false

Effects of Solidification Parameters on Lamellar Microstructures of Near Eutectic Cr-Cr3Si Alloys

Published online by Cambridge University Press:  11 February 2011

H. Bei
Affiliation:
The University of Tennessee, Department of Materials Science and Engineering, Knoxville, TN 37996–2200
E. P. George
Affiliation:
The University of Tennessee, Department of Materials Science and Engineering, Knoxville, TN 37996–2200 Oak Ridge National Laboratory, Metals and Ceramics Division, Oak Ridge, TN 37831–6093
G. M. Pharr
Affiliation:
The University of Tennessee, Department of Materials Science and Engineering, Knoxville, TN 37996–2200 Oak Ridge National Laboratory, Metals and Ceramics Division, Oak Ridge, TN 37831–6093
Get access

Abstract

Directional solidification of Cr-Cr3Si eutectic alloys has been carried out using a high temperature optical floating zone furnace. Uniform and well-aligned lamellar structures were obtained over a fairly wide range of intermediate growth rates but not at very low or very high growth rates where degenerate and cellular structures, respectively, were obtained. The lamellar spacing was found to increase with decreasing solidification rate, in agreement with the Jackson-Hunt theory. In addition, for a fixed growth rate, the lamellar spacing was found to increase with increasing rotation rate. Lamellar structures could also be produced at off-eutectic compositions, but only for a limited range of growth conditions. The Cr-rich lamellae are effective in stopping indention cracks nucleated in the brittle Cr3Si phase.

Type
Research Article
Copyright
Copyright © Materials Research Society 2003

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. Bewlay, B. P., Sutliff, J. A., Jackson, M. R. and Chang, K-M., Materials and Manufacturing Processes 9 (1994) 89.Google Scholar
2. Chang, K-M., Bewlay, B. P., Sutliff, J. A. and Jackson, M. R., JOM 44 (1992) 59.Google Scholar
3. Newkirk, J. W. and Sago, J. A., Mat. Res. Soc. Symp. Proc. 194 (1990) 183.Google Scholar
4. Bewlay, B.P., Chang, K-M., Sutliff, J. A. and Jackson, M. R., Mat. Res. Soc. Symp. Proc. 273 (1992) 417.Google Scholar
5. Gokhale, A. B. and Abbaschian, G.J., Bulletin of Alloy Phase Diagrams 8 (1987) 474.Google Scholar
6. Chang, Y.A., Transactions of the Metallurgical Society of AIME 242 (1968) 1509.Google Scholar
7. Jackson, K. A. and Hunt, J. D., Trans. of the Met. Soc. of AIME 236 (1966) 1129.Google Scholar
8. Caram, R., Nanan, M. and Wilcox, W. R., Journal of Crystal Growth 114 (1991) 249.Google Scholar
9. Eisa, G. F., Wilcox, W. R. and Busch, G., Journal of Crystal Growth 78 (1986) 159.Google Scholar
10. Ma, D., Jie, W.Q., Li, Y. and Ng, S.C., Acta Mater. 46 (1998) 3203.Google Scholar
11. Flemings, M. C., Solidification Processing, Published by McGraw-Hill, Inc., 1974.Google Scholar