Experimental Observation of a Time-Scaling Characteristic in Alloy Decomposition in the AlZnMg System

Neutron-scattering results on the decomposition in two AlZnMg alloys, after three different quenching procedures and for three annealing temperatures, can be represented by an unique curve if reduced variables for Guinier radius, $\rho =\frac{R_G\mathrm{}\left(t\right)\mathrm{}}{R_0}$, and the volume fraction of clusters, $v=\frac{V\left(t\right)\mathrm{}}{V_{\infty }}$, are used. The invariant curve $\rho$ vs $v$ reflects predominant nucleation at the beginning—i. e., increase of volume fraction connected with a small variation of $R_G$—and the coarsening regime when the equilibrium volume fraction is approached.