On the reversion of G P zones in AI-10% Zn and AI-10% Zn-0.1% Mg alloys

Abstract

Most of the previous studies on spherical G P zones, which characterise the pre-precipitation process in the Al-Zn alloys, were related to their formation and growth [1 5]. However, very few of them have been concerned with reversion, i.e. dissolution of the G P zones that results when the solid solution containing them is heated above a given temperature. This tem perature is determined, for a given composition of the alloy considered, by the metastable miscibility gap which seems to control the formation of such zones.