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A Reassessment of the Metastable Miscibility Gap in Al-Ag Alloys by Atom Probe Tomography

Published online by Cambridge University Press:  14 November 2007

Emmanuelle A. Marquis
Affiliation:
Materials Physics Department, Sandia National Laboratories, P.O. Box 969, MS 9161, Livermore, CA 94550, USA
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Abstract

The evolution of Guinier-Preston zones in an Al-2.7 at.% Ag alloy was studied using atom probe tomography. The composition and morphology of the GP zones are time dependent, explaining discrepancies in previous work. This result requires the metastable miscibility gap for GP zones to be reevaluated, highlighting the importance of the temporal evolution of the GP zones. Preliminary results on the composition of γ′ and γ plates are also presented.

Type
Research Article
Copyright
© 2007 Microscopy Society of America

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References

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Marquis

Figure 11. GP zones, a (gamma)' plate and the Ag-depleted zone around it

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