The aim of the work is to study mechanical and thermal properties and microstructure development of the cold-rolled Al-Zn-Mg-(Sc-Zr) alloy during the isochronal annealing. The distinct changes in microhardness curves as well as in heat flow of the alloys studied are mainly caused by dissolution of the Guiner-Prestonzones and subsequent precipitation of the metastable phase η' from the Al-Zn-Mg system.
The apparent activation energies of the processes were also calculated.