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The Activation Parameters And The Mechanisms Of Plastic Deformation Of Al-Pd-Mn Single Quasicrystals

Published online by Cambridge University Press:  10 February 2011

U. MessersChmidt
Affiliation:
Max Planck Institute of Microstructure Physics, Halle/S., D-06120, Germany
B. Geyer
Affiliation:
Max Planck Institute of Microstructure Physics, Halle/S., D-06120, Germany
M. Bartsch
Affiliation:
Max Planck Institute of Microstructure Physics, Halle/S., D-06120, Germany
M. Feuerbacher
Affiliation:
Institute of Solid State Research, Jtilich Research Centre, Jolich, D-52425, Germany
K. Urban
Affiliation:
Institute of Solid State Research, Jtilich Research Centre, Jolich, D-52425, Germany
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Abstract

In situ straining experiments on Al-Pd-Mn single quasicrystals in a high-voltage electron microscope between 675 °C and 750°C showed viscously moving dislocations with segments oriented in preferred directions. First measurements from video recordings indicate that dislocations on parallel traces move at two different velocities. For the first time, macroscopic samples were deformed in compression below 680 °C. Above a transition temperature of about 635°C for specimens of a fivefold compression axis and a strain rate of 10−5 s−1, the specimens show a yield point followed by a range of steady state deformation. Below that temperature, they are brittle. However, plastic deformation was achieved down to 555°C by using a lower strain rate and performing stress relaxation tests before the fracture stress was reached. The samples then show very strong work-hardening. The rapid decrease of the activation volume with decreasing temperature, which is characteristic of the high-temperature range, does not continue at low temperatures.The results are interpreted by dislocation generation and recovery and by the cluster friction mechanism controlling the dislocation mobility.

Type
Research Article
Copyright
Copyright © Materials Research Society 1999

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References

REFERENCES

1. Wollgarten, M., Beyss, M., Urban, K., Liebertz, H., and Köster, U., Phys. Rev. Lett., 71, 549 (1993).Google Scholar
2. Wollgarten, M., Bartsch, M., Messerschmidt, U., Feuerbacher, M., Rosenfeld, R., Beyss, M., and Urban, K., Phil. Mag. Lett. 71, 99 (1995).Google Scholar
3. Messerschmidt, U., Geyer, B., Bartsch, M., Feuerbacher, M., and Urban, K. in Quasicrystals, Proc. 6th Int. Congr. on Quasicrystals, Tokyo, 1997, (World Scientific, Singapore 1998), p. 509.Google Scholar
4. Feuerbacher, M., Baufeld, B., Rosenfeld, R., Bartsch, M., Hanke, G., Beyss, M., Wollgarten, M., Messerschmidt, U., and Urban, K., Phil. Mag. Lett. 71, 91 (1995).Google Scholar
5. Feuerbacher, M., Metzmacher, C., Wollgarten, M., Urban, K., Baufeld, B., Bartsch, M., and Messerschmidt, U., Mater. Sci. Eng. A 233, 103 (1997).Google Scholar
6. Urban, K., Ebert, Ph., Feuerbacher, M., Franz, V., Wollgarten, M., Bartsch, M., Baufeld, B., and Messerschmidt, U. in Quasicrystals, Proc. 6th Int. Congr. on Quasicrystals, Tokyo, 1997,(World Scientific, Singapore 1998), p. 493.Google Scholar
7. Geyer, B., Bartsch, M., Feuerbacher, M., Urban, K., and Messerschmidt, U., to be submitted to Phil. Mag. A.Google Scholar
8. Schall, P., Feuerbacher, M., Bartsch, M., Messerschmidt, U., and Urban, K., to be published; P. Schall, Diploma Thesis, Aachen 1998.Google Scholar
9. Messerschmidt, U. and Bartsch, M., Ultramicroscopy 56, 163 (1994).Google Scholar
10. Rosenfeld, R., Feuerbacher, M., Baufeld, B., Bartsch, M., Wollgarten, M., Hanke, G.,Beyss, M., Messerschmidt, U., and Urban, K., Phil. Mag. Lett. 72, 375 (1995).Google Scholar
11. Messerschmidt, U., Bartsch, M., Geyer, B., Feuerbacher, M., and Urban, K., to be submitted to Phil. Mag. A.Google Scholar
12. Schöck, G., Phys. Status Solidi 8, p. 499 (1965).Google Scholar
13. Feuerbacher, M., Weller, M., Diehl, J., and Urban, K., Phil. Mag. Lett. 74, 81 (1996).Google Scholar
14. Messerschmidt, U., Bartsch, M., Feuerbacher, M., Geyer, B., and Urban, K., to be published in Phil. Mag. AGoogle Scholar
15. Labusch, R. and Schwarz, R.B. in Strength of Metals and Alloys, edited by Brandon, D.G.,Chaim, R., and Rosen, A. (Freund Publ., London 1991), p. 47.Google Scholar