Understanding the Role of Cu and Clustering on Strain Hardening and Strain Rate Sensitivity of Al-Mg-Si-Cu Alloys

  • M. Langille
  • B. J. Diak
  • F. De Geuser
  • G. Guiglionda
  • S. Meddeb
  • H. Zhao
  • B. Gault
  • D. Raabe
  • A. DeschampsEmail author
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


Increased demand for light-weighting in passenger vehicles has created a need for strong, light, ductile materials to be used in body-in-white applications. The AA6xxx-series of aluminum alloys are suitable candidates meeting most requirements but can fall short of the formability demands of designers, necessitating an understanding of what controls the formability in this alloy series. This work examines the effect of copper alloying in AA6xxx on the pre-ageing and natural ageing responses of the microstructure and mechanical properties. The changes in microstructure observed by differential scanning calorimetry and hardness testing are related to the work-hardening and strain-rate sensitivity parameters for these alloys measured by tensile testing. An observed asymmetry in the measured strain-rate sensitivity associated with increasing versus decreasing strain rate changes suggests that a different mechanism operates for the two conditions. It is postulated how this asymmetry in strain-rate sensitivity will impact the necking and ductility behaviour of these alloys.


Al-Mg-Si-Cu Clusters Ductility Natural ageing Strain-rate sensitivity Tensile test Work-hardening 



The author would like to thank the Association Nationale Recherche Technologie (ANRT) for co-funding the project and Devang Sejani for performing the extensive hardness testing found in this work. This paper was first published in the proceedings of the 16th International Aluminum Alloys Conference (ICAA16) 2018 ISBN: 978-1-926872-41-4.


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Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  • M. Langille
    • 1
    • 2
  • B. J. Diak
    • 3
  • F. De Geuser
    • 1
  • G. Guiglionda
    • 2
  • S. Meddeb
    • 1
  • H. Zhao
    • 4
  • B. Gault
    • 4
  • D. Raabe
    • 4
  • A. Deschamps
    • 1
    Email author
  1. 1.Université Grenoble Alpes, CNRS, Grenoble INP, SIMaPGrenobleFrance
  2. 2.Constellium Technology Center (C-TEC)VoreppeFrance
  3. 3.Mechanical and Materials EngineeringQueen’s UniversityKingstonCanada
  4. 4.Max-Planck-Institut Fr EisenforschungDsseldorfGermany

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