Abstract

This paper compares the nano-scale structure of β” precipitates in a peak-aged Al-Mg-Si alloy before and after deformation. Three complementary advanced transmission electron microscopy techniques are used to reveal the structures and elucidate the interaction between dislocations and β” precipitates. We show that the needle-like and semi-coherent β” precipitates are sheared several times on different planes by dislocations during deformation, with no indications that they are bypassed or looped. Our results show that dislocations cut through precipitates and leave behind planar defects lying on planes inclined to 〈100〉 directions inside the precipitates. The results also indicate that precipitates are sheared in single steps, and the implication of this observation is discussed in terms of slip behaviour.

Details

Title
Nano-scale characterisation of sheared β” precipitates in a deformed Al-Mg-Si alloy
Author
Christiansen, Emil 1   VIAFID ORCID Logo  ; Calin Daniel Marioara 2 ; Holmedal, Bjørn 3 ; Hopperstad, Odd Sture 4 ; Holmestad, Randi 1 

1  Centre for Advanced Structural Analysis (CASA), NTNU - Norwegian University of Science and Technology, Trondheim, Norway; Department of Physics, Faculty of Natural Sciences, NTNU, Trondheim, Norway 
2  Centre for Advanced Structural Analysis (CASA), NTNU - Norwegian University of Science and Technology, Trondheim, Norway; Materials and Nanotechnology, SINTEF Industry, Trondheim, Norway 
3  Centre for Advanced Structural Analysis (CASA), NTNU - Norwegian University of Science and Technology, Trondheim, Norway; Department of Materials Science and Engineering, Faculty of Natural Sciences, NTNU, Trondheim, Norway 
4  Centre for Advanced Structural Analysis (CASA), NTNU - Norwegian University of Science and Technology, Trondheim, Norway; Department of Structural Engineering, Faculty of Engineering, NTNU, Trondheim, Norway 
Pages
1-11
Publication year
2019
Publication date
Nov 2019
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
DOI
https://doi.org/10.1038/s41598-019-53772-4
ProQuest document ID
2317925483
Copyright
© 2019. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.