On the Nature of Point Defects Assisting Zn Clustering in Al-Zn 10% Alloy

Results of new resistometric investigations on the ageing after cold-work of an Al-Zn 10% alloy, as well as results of previous experiments on this alloy, are analysed in the light of the main different models advanced for the recovery stage III in Al. A new interesting phenomenon observed in the isothermal ageing after low deformation, namely a slowing down of the initial clustering rate by raising the temperature in the neighbourhood of −50°c, appears explicable only by the vacancy model for stage III.