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Thermally Activated Unpinning of Screw Dislocations in the Anomalous Regime in L12 Compounds

Published online by Cambridge University Press:  01 January 1992

M. Khantha
Affiliation:
Department of Materials Science and EngineeringUniversity of PennsylvaniaPhiladelphia, PA 19104-6272.
J. Cserti
Affiliation:
Department of Materials Science and EngineeringUniversity of PennsylvaniaPhiladelphia, PA 19104-6272.
V. Vitek
Affiliation:
Department of Materials Science and EngineeringUniversity of PennsylvaniaPhiladelphia, PA 19104-6272.
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Abstract

We present a model for the anomalous increase of the yield stress exhibited by many L12 compounds. It is based on two thermally activated processes that describe respectively the pinning and unpinning of [101] screw dislocations in the (111) plane. The model explains all the important characteristic features observed in the anomalous regime. We discuss the applications of the model to Ni3Ga and Ni3(Al,Ta).

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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References

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