Effect of Zn or Zn + Cu Addition on the Precipitation in Al–Mg–Si Alloys: A Review.

The effect of Zn or Zn + Cu addition on the precipitation in Al–Mg–Si alloys is summarized and analyzed by analyzing DSC curves, aging strengthening curves, and precipitates, which is very helpful for Al–Mg–Si alloys industrial application. With Zn addition, the hardness of Al–Mg–Si alloys increased, and the peak aging time might shorten or increase, which might be related to the Mg/Si atomic ratio. With Zn + Cu addition, the effects on the age-hardening curves of Al–Mg–Si alloys depended on the Zn + Cu content and aging system. With Zn addition, the precipitation of Al–Mg–Si alloy changed, such as the appearance of η′ and the composition and structure of β″ and β′. With Zn + Cu addition, the precipitation of Al–Mg–Si alloys changed, such as the composition of Mg–Si phases and the activation energy of β″. Moreover, items that require attention in future investigations were pointed out, including activation energy, location of Zn and Cu atoms in precipitation, etc. [ABSTRACT FROM AUTHOR]