Characterization of Precipitation in Al-Li Alloy AA2195 by means of Atom Probe Tomography and Transmission Electron Microscopy

Handle URI:
http://hdl.handle.net/10754/561079
Title:
Characterization of Precipitation in Al-Li Alloy AA2195 by means of Atom Probe Tomography and Transmission Electron Microscopy
Authors:
Khushaim, Muna; Boll, Torben; Seibert, Judith; Haider, Ferdinand; Al-Kassab, Talaat
Abstract:
The microstructure of the commercial alloy AA2195 was investigated on the nanoscale after conducting T8 tempering. This particular thermomechanical treatment of the specimen resulted in the formation of platelet-shaped T 1 Al 2 CuLi / θ ′ Al 2 Cu precipitates within the Al matrix. The electrochemically prepared samples were analyzed by scanning transmission electron microscopy and atom probe tomography for chemical mapping. The θ ′ platelets, which are less than 2 nm thick, have the stoichiometric composition consistent with the expected Al 2 Cu equilibrium composition. Additionally, the Li distribution inside the θ ′ platelets was found to equal the same value as in the matrix. The equally thin T 1 platelet deviates from the formula (Al 2 CuLi) in its stoichiometry and shows Mg enrichment inside the platelet without any indication of a higher segregation level at the precipitate/matrix interface. The deviation from the (Al 2 CuLi) stoichiometry cannot be simply interpreted as a consequence of artifacts when measuring the Cu and Li concentrations inside the T 1 platelet. The results show rather a strong hint for a true lower Li and Cu contents, hence supporting reasonably the hypothesis that the real chemical composition for the thin T 1 platelet in the T8 tempering condition differs from the equilibrium composition of the thermodynamic stable bulk phase.
KAUST Department:
Physical Sciences and Engineering (PSE) Division
Citation:
Characterization of Precipitation in Al-Li Alloy AA2195 by means of Atom Probe Tomography and Transmission Electron Microscopy 2015, 2015:1 Advances in Condensed Matter Physics
Publisher:
Hindawi Publishing Corporation
Journal:
Advances in Condensed Matter Physics
Issue Date:
19-May-2015
DOI:
10.1155/2015/647468
Type:
Article
ISSN:
1687-8108; 1687-8124
Additional Links:
http://www.hindawi.com/journals/acmp/2015/647468/
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorKhushaim, Munaen
dc.contributor.authorBoll, Torbenen
dc.contributor.authorSeibert, Judithen
dc.contributor.authorHaider, Ferdinanden
dc.contributor.authorAl-Kassab, Talaaten
dc.date.accessioned2015-07-27T12:22:02Zen
dc.date.available2015-07-27T12:22:02Zen
dc.date.issued2015-05-19en
dc.identifier.citationCharacterization of Precipitation in Al-Li Alloy AA2195 by means of Atom Probe Tomography and Transmission Electron Microscopy 2015, 2015:1 Advances in Condensed Matter Physicsen
dc.identifier.issn1687-8108en
dc.identifier.issn1687-8124en
dc.identifier.doi10.1155/2015/647468en
dc.identifier.urihttp://hdl.handle.net/10754/561079en
dc.description.abstractThe microstructure of the commercial alloy AA2195 was investigated on the nanoscale after conducting T8 tempering. This particular thermomechanical treatment of the specimen resulted in the formation of platelet-shaped T 1 Al 2 CuLi / θ ′ Al 2 Cu precipitates within the Al matrix. The electrochemically prepared samples were analyzed by scanning transmission electron microscopy and atom probe tomography for chemical mapping. The θ ′ platelets, which are less than 2 nm thick, have the stoichiometric composition consistent with the expected Al 2 Cu equilibrium composition. Additionally, the Li distribution inside the θ ′ platelets was found to equal the same value as in the matrix. The equally thin T 1 platelet deviates from the formula (Al 2 CuLi) in its stoichiometry and shows Mg enrichment inside the platelet without any indication of a higher segregation level at the precipitate/matrix interface. The deviation from the (Al 2 CuLi) stoichiometry cannot be simply interpreted as a consequence of artifacts when measuring the Cu and Li concentrations inside the T 1 platelet. The results show rather a strong hint for a true lower Li and Cu contents, hence supporting reasonably the hypothesis that the real chemical composition for the thin T 1 platelet in the T8 tempering condition differs from the equilibrium composition of the thermodynamic stable bulk phase.en
dc.publisherHindawi Publishing Corporationen
dc.relation.urlhttp://www.hindawi.com/journals/acmp/2015/647468/en
dc.rightsThis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. http://creativecommons.org/licenses/by/3.0/en
dc.titleCharacterization of Precipitation in Al-Li Alloy AA2195 by means of Atom Probe Tomography and Transmission Electron Microscopyen
dc.typeArticleen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalAdvances in Condensed Matter Physicsen
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionDepartment of Applied Physics, Chalmers University of Technology, 412 96 Goteborg, Swedenen
dc.contributor.institutionUniversity of Augsburg, Institute of Physics, 86159 Augsburg, Germanyen
kaust.authorAl-Kassab, Talaaten
kaust.authorKhushaim, Munaen
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