Clustering and precipitation processes in age-hardened Al-Zn-Mg-(Ag, Cu) alloys

New observations are reported herein on clustering and precipitation processes in agehardened Al-Zn-Mg-(Ag, Cu) alloys... This analysis has led to a proposal for the reconceptualisation of the composition, orientation and structure of n1. Based on these results, it has been concluded that Ag enhances the agehardening response of Al-Zn-Mg alloys in the range 120 - 200 °C, by stimulating fine and uniformly dispersed pre-precipitate clustering processes involving Ag atoms and vacancies. […]