Li-atoms-induced structure changes of Guinier–Preston–Bagaryatsky zones in AlCuLiMg alloys

Journal Article · Tue Nov 15 04:00:00 EST 2016 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2016.09.037· OSTI ID:22689657

Duan, S. Y.; Le, Z.; Chen, Z. K.; Gao, Z. ^[1]; Ming, W. Q.; Li, S. Y.; Wu, C. L. ^[1]; Yan, N. ^[2]

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1. Center for High-Resolution Electron Microscopy, College of Materials Science and Engineering, Hunan University, Changsha, Hunan 410082 (China)
2. Advanced Research Center, Central South University, Changsha 410083 (China)

Guinier–Preston–Bagaryatsky (GPB) zones are the well-known strengthening precipitates of AlCuMg alloys formed upon thermal ageing. Here we report that when formed in AlCuLiMg alloys the GPB zones can change significantly in morphology and structure. It is shown that though they do still consist of Al, Cu and Mg elements fundamentally, the GPB zones in AlCuLiMg alloys have a rather different structure due to a featured Li-segregation at their interfaces with the matrix and possible Li-replacement of partial Mg atoms in the structure. As such the Li-containing GPB zones often develop from one-dimensional to quasi-two-dimensional precipitates. - Highlights: • We observe Guinier–Preston–Bagaryatsky zone variants in AlCuLiMg alloys. • We obtain atomic-resolution images of the precipitates and model their structures. • Li-atoms play a key role in modifying the structure of these precipitate variants.

• OSTI ID: 22689657
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Vol. 121; ISSN 1044-5803; ISSN MACHEX
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AGING
ALUMINIUM BASE ALLOYS
ATOMS
COPPER ALLOYS
ELECTRON MICROSCOPY
IMAGES
INTERFACES
LITHIUM
LITHIUM ALLOYS
MAGNESIUM ALLOYS
MATRICES
MICROSTRUCTURE
MORPHOLOGY
ONE-DIMENSIONAL CALCULATIONS
PRECIPITATION
RESOLUTION
SEGREGATION
TWO-DIMENSIONAL CALCULATIONS