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Study of the effect of Al, Cr and Sn additions on the microstructure and properties of Nb silicide based alloys

Published online by Cambridge University Press:  04 February 2011

P Tsakiropoulos ,
K Zelenitsas  and
N Vellios
P Tsakiropoulos
Affiliation:
Department of Materials Science and Engineering, The University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD, England, UK
K Zelenitsas
Affiliation:
Department of Materials Science and Engineering, The University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD, England, UK
N Vellios
Affiliation:
Department of Materials Science and Engineering, The University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD, England, UK
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Abstract

The effects of Al, Cr and Sn on segregation, microstructure, phase stability and hardness of Nb-24Ti-18Si-5X (X = Al, Cr, Sn, at%) alloys were studied. The microstructure of the as cast alloys with Cr, Al and Sn respectively contained (Nb,Ti)ss, Nb3Si, αNb5Si3 and C14-NbCr2 Laves, (Nb,Ti)ss and βNb5Si3 and (Nb,Ti)ss, Nb3Sn and Nb5Si3. The microstructures of the heat treated alloys with Al and Cr (1500 oC/100 h) contained (Nb,Ti)ss and αNb5Si3 and the alloy with Sn (1200 oC/100 h) contained (Nb,Ti)ss, Nb3Sn and αNb5Si3. Compared with Al and Cr, alloying with Sn enhanced the stability of the as cast microstructure, caused strong macrosegregation of Si and Ti, suppressed the segregation of Ti in the (Nb,Ti)ss that was promoted by Al and Cr, had the strongest effect on the macrohardness of the cast and heat treated alloys and on the vol% of the Nbss. All three alloying additions promoted the transformation of βNb5Si3 to αNb5Si3 during heat treatment and decreased the hardness of Nb5Si3 in the as cast alloys with Sn having the strongest effect and Al the weakest. After the heat treatment the hardness of Nb5Si3 increased in the alloys containing Cr and Sn and decreased in the Al containing alloy with Cr having the strongest effect.

Keywords

phase transformationNballoy
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1295: Symposium N – Intermetallic-Based Alloys for Structural and Functional Applications , 2011 , mrsf10-1295-n07-05
Copyright
Copyright © Materials Research Society 2011

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References

REFERENCES

1. Bewlay, B. P., Jackson, M. R., Lipsitt, H. A., Metall. Mater. Trans. A, 27, 3801 (1996)Google Scholar
2. Chan, Kwai S., Mater. Sci. Eng. A, 409, 257 (2005)Google Scholar
3. Grammenos, I. and Tsakiropoulos, P., Intermetallics, 18, 1524 (2010)Google Scholar
4. Geng, J., Tsakiropoulos, P. and Shao, G., Intermetallics, 15, 69 (2007)Google Scholar
5. Vellios, N. and Tsakiropoulos, P., Intermetallics, 18, 1729 (2010)Google Scholar
6. Grammenos, I. and Tsakiropoulos, P., Intermetallics, 18, 242 (2010)Google Scholar
7. Kim, W-Y., Tanaka, H., Kasama, A. and Hanada, S., Journal of Alloys and Compounds, 333, 170 (2002)Google Scholar
8. Grill, R. and Gnadenberger, A., Int. J. Refract. Met. Hard Mater., 24, 275 (2006)Google Scholar
9. Zelenitsas, K. and Tsakiropoulos, P., Mater. Sci. Eng. A, 416, 269 (2006)Google Scholar
10. Geng, J., Tsakiropoulos, P. and Shao, G., Mater. Sci. Eng. A, 441, 26 (2006)Google Scholar
11. Zelenitsas, K. and Tsakiropoulos, P., Intermetallics, 13, 1079 (2005)Google Scholar
12. Geng, J., Tsakiropoulos, P., Intermetallics, 15, 382 (2007)Google Scholar
13. Vellios, N. and Tsakiropoulos, P., Intermetallics, 15, 1518 (2007)Google Scholar
14. Schlesinger, M. E., Okamoto, H., Gokhale, A. B. and Abbaschian, R., Journal of Phase Equilibria, 14, 502 (1993)Google Scholar