The Effect of Deformation on the Work Hardening Behaviour after Aging of Two Commercial Al-Mg-Si Alloys

Abstract:

In order to investigate the effect of deformation on the aging response of Al-Mg-Si alloys, a series of tensile tests have been designed and carried out on two commercial aluminium alloys, i.e. AA6060 and AA6082. Extruded and solution heat treated specimens were pre-deformed 0%, 5%, and 10% (engineering strain), respectively followed by natural aging (NA). It was observed that the work-hardening rate increases with prolonged natural aging time and decreases with increasing pre-deformation prior to natural aging. The most significant effect of deformation was obtained for T4 temper i.e. after 1000 and 10000 minutes NA for the 6082 and 6060 alloy, respectively, when the amount of pre-deformation is 10%. A remarkable difference in work-hardening rate at the level of small plastic strains was observed compared to that of the material naturally aged for only 10 minutes. In addition to the tensile tests, transmission electron microscopy (TEM) has been used to characterize dislocation evolution for various combinations of pre-deformation and aging time.

• Periodical: Materials Science Forum (Volumes 638-642)
• Pages: 261-266
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.638-642.261
• Online since: January 2010
• Authors: Michal Kolar, Ketill Olav Pedersen, Sverre Gulbrandsen-Dahl, Thiemo Brüggemann, Knut Marthinsen
• Keywords: Al-Mg-Si Alloy, Natural Aging, Pre-Deformation, TEM, Work-Hardening

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