Hostname: page-component-745bb68f8f-grxwn Total loading time: 0 Render date: 2025-01-12T10:03:56.908Z Has data issue: false hasContentIssue false
  • English
  • Français

Characterizing Deformation Mechanisms in Ni3Ge-Fe3Ge Intermetallic Alloys

Published online by Cambridge University Press:  10 February 2011

T. J. Balk ,
Mukul Kumar ,
O. N. Mryasov ,
A. J. Freeman  and
K. J. Hemker
T. J. Balk
Affiliation:
Dept. of Mechanical Engineering, Johns Hopkins University, Baltimore, MD 21218-2686
Mukul Kumar
Affiliation:
Univ. of California, Lawrence Livermore National Laboratory, L-370, Livermore, CA 94550
O. N. Mryasov
Affiliation:
Dept. of Physics and Astronomy, Northwestern University, Evanston, IL 60208-3112
A. J. Freeman
Affiliation:
Dept. of Physics and Astronomy, Northwestern University, Evanston, IL 60208-3112
K. J. Hemker
Affiliation:
Dept. of Mechanical Engineering, Johns Hopkins University, Baltimore, MD 21218-2686
Get access

Abstract

The Ni3Ge-Fe3Ge model system provides us with a unique opportunity to characterize the mechanisms of deformation in both anomalous and normal L12 intermetallic alloys. The elastic moduli of alloys in this system have been measured and used as benchmarks for first principles calculations. At 77K, increasing the Fe content has been found to result in a dramatic increase in flow stress. The Ni-rich alloys exhibit a yield strength anomaly, but as Ni is replaced by Fe, the anomalous temperature dependence gradually disappears, and no yield strength anomaly is observed for alloys with more than 25 at% Fe. At low temperatures and Fe contents, the deformation microstructure has been found to be dominated by Kear-Wilsdorf locking; but a transition from octahedral glide and Kear-Wilsdorf locking to cube glide is observed as either Fe content or temperature is increased. This transition is related to changes that occur in the core structures of dissociated superdislocations and planar fault energies measured through computer simulations of weak-beam TEM images.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 552: Symposium KK – High-Temperature Ordered Intermetallic Alloys VIII , 1998 , KK10.8.1
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. Haasen, P., Physical Metallurgy, 3rd ed. (Cambridge University Press, Cambridge, 1996).CrossRefGoogle Scholar
2. Nabarro, F.R.N. and Duesbery, M.S., (eds.), Dislocations in Solids, vol.10 (Elsevier Science B.V., Amsterdam, 1996).Google Scholar
3. Wee, D.M., Noguchi, O., Oya, Y. and Suzuki, T., Trans. Jap. Inst. Metals 21, 237 (1980).CrossRefGoogle Scholar
4. Pak, H.R., Saburi, T. and Nenno, S., Trans. Jap. Inst. Metals 18, 617 (1977).CrossRefGoogle Scholar
5. Suzuki, T., Oya, Y. and Wee, D.M., Acta Metall. 28, 301 (1980).CrossRefGoogle Scholar
6. Ngan, A.H.W., Jones, I.P. and Smallman, R.E., Mater. Sci. Eng. A 153, 387 (1992).CrossRefGoogle Scholar
7. Flinn, P.A., Trans. AIME 218, 125 (1960).Google Scholar
8. Yoo, M.H., Acta Metall. 35, 1559 (1987).CrossRefGoogle Scholar
9. Saada, G. and Veyssiere, P., Phil. Mag. A 66, 1081 (1992).CrossRefGoogle Scholar
10. Kear, B.H. and Wilsdorf, H.G.F., Trans. AIME 224, 382 (1962).Google Scholar
11. Hemker, K.J. and Mills, M.J., Phil. Mag. A 68, 305 (1993).CrossRefGoogle Scholar
12. Schdiublin, R. and Stadelmann, P., Mater. Sci. Eng. A164, 373 (1993).CrossRefGoogle Scholar
13. Mryasov, O.N., Gornostyrev, Y.N. and Freeman, A.J., Phys. Rev. B 58, 11927 (1998).CrossRefGoogle Scholar
14. Shi, X., Saada, G. and Veyssiere, P., Phil. Mag. A 73, 1419 (1996).Google Scholar
15. Yasuda, H., Takasugi, T. and Koiwa, M., Acta Metall. 40, 381 (1992).CrossRefGoogle Scholar
16. Hill, R., Proc. Phys. Soc. A 65, 349 (1952).Google Scholar
17. Kumar, M., Balk, T.J. and Hemker, K.J., Proc. MRS Fall 1998 Meeting, in press, 538 (1998).CrossRefGoogle Scholar