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High-temperature Dislocation-precipitate Interactions in Al Alloys: An in situ Transmission Electron Microscopy Deformation Study

Published online by Cambridge University Press:  01 July 2005

B.G. Clark ,
I.M. Robertson ,
L.M. Dougherty ,
D.C. Ahn  and
P. Sofronis
B.G. Clark
Affiliation:
Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801
I.M. Robertson*
Affiliation:
Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801
L.M. Dougherty
Affiliation:
Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801
D.C. Ahn
Affiliation:
Department of Theoretical and Applied Mechanics, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801
P. Sofronis
Affiliation:
Department of Theoretical and Applied Mechanics, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801
*
a)Address all correspondence to this author. e-mail: ianr@uiuc.edu This author was an editor of this focus issue during the review and decision stage. For the JMR policy on review and publication of manuscripts authored by editors, please refer to http://www.mrs.org/publications/jmr/policy.html.
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Abstract

The fundamental processes controlling the high-temperature interaction of dislocations with precipitates in Al-alloys were investigated in real time by deforming specimens in situ in the transmission electron microscope at elevated temperature. The observations support a bypass mechanism involving the interaction of lattice dislocations with the precipitate–matrix interface dislocations, where the rate-limiting step in the interaction is the release of the dislocation from the particle. These observations are discussed in relation to high-temperature deformation processes and models.

Keywords

AlloyDislocationsTransmission electron microscopy (TEM)
Type
Articles
Information
Journal of Materials Research , Volume 20 , Issue 7 , July 2005 , pp. 1792 - 1801
Copyright
Copyright © Materials Research Society 2005

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References

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