To main content

Studying GPI zones in Al-Zn-Mg alloys by 4D-STEM

Abstract

A new methodology has been developed to study the fine details of GP zones in age-hardenable aluminium alloys. It is complementary to atomic resolution high-angle annular dark-field scanning transmission electron microscopy imaging, and combines scanning precession electron diffraction with diffraction simulations. To evaluate the method, data was collected from an Al-Zn-Mg alloy in a condition with a dense distribution of GPI zones. Diffraction patterns were recorded in the 〈001Al orientation, capturing GPI zones in three projections: along the unique [001]GPI axis, and along the two other mutually orthogonal orientations. The GPI zones viewed along [001]GPI revealed how the truncated octahedron units of the GPI zones were connected in multi-unit GP zones, while the two orientations normal to [001]GPI highlight the internal structure. The stability of the atomic models developed based on the experimental results was verified by density functional theory calculations.

Category

Academic article

Client

  • Research Council of Norway (RCN) / 197405
  • Norwegian University of Science and Technology / DIGITAL TRANSFORMATION
  • Research Council of Norway (RCN) / 294933
  • Notur/NorStore / NN9158K
  • Notur/NorStore / NN8068K

Language

English

Author(s)

Affiliation

  • Norwegian University of Science and Technology
  • SINTEF Industry / Materials and Nanotechnology

Year

2021

Published in

Materials Characterization

ISSN

1044-5803

Publisher

Elsevier

Volume

185

View this publication at Cristin