Dislocation substructures in pure aluminium after creep deformation as studied by electron backscatter diffraction

Itziar Serrano-Munoz; Ricardo Fernández; Romeo Saliwan-Neumann; Gaspar González-Doncel; Giovanni Bruno

doi:10.1107/S1600576722005209

Dislocation substructures in pure aluminium after creep deformation as studied by electron backscatter diffraction

J Appl Crystallogr. 2022 Jul 5;55(Pt 4):860-869. doi: 10.1107/S1600576722005209. eCollection 2022 Aug 1.

Authors

Itziar Serrano-Munoz¹, Ricardo Fernández², Romeo Saliwan-Neumann¹, Gaspar González-Doncel², Giovanni Bruno^{1

3}

Affiliations

¹ Bundesanstalt für Materialforschung und -prüfung (BAM), Unter Den Eichen 87, Berlin, 12205, Germany.
² Department of Physical Metallurgy, Centro Nacional de Investigaciones Metalúrgicas (CENIM), Avenida de Gregorio del Amo No. 8, Madrid, E-28040, Spain.
³ Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Strasse 24-25, Potsdam, 14476, Germany.

Abstract

In the present work, electron backscatter diffraction was used to determine the microscopic dislocation structures generated during creep (with tests interrupted at the steady state) in pure 99.8% aluminium. This material was investigated at two different stress levels, corresponding to the power-law and power-law breakdown regimes. The results show that the formation of subgrain cellular structures occurs independently of the crystallographic orientation. However, the density of these cellular structures strongly depends on the grain crystallographic orientation with respect to the tensile axis direction, with 〈111〉 grains exhibiting the highest densities at both stress levels. It is proposed that this behaviour is due to the influence of intergranular stresses, which is different in 〈111〉 and 〈001〉 grains.

Keywords: cellular structures; creep; electron backscatter diffraction (EBSD); power law and power-law breakdown; pure aluminium.

Grants and funding

This project was partially financed by the Spanish MINECO program, corresponding to Project MAT2017-83825-C4-1-R, and by the project Y2018/NMT-4668 Micro-Stress-MAP-C from Comunidad Autónoma de Madrid, Spain.