Diffusion of65Zn in AlZn solid solutions

The diffusion coefficients of 65Zn in AlZn solid solutions were measured by means of sectioning techniques for x = 0 to 60 at% Zn content between 315 and 650 °C. Since no generally accepted atomistic theory exists for diffusion in concentrated solid solutions, the results are interpreted by an empirical rule proposed by Kučera and Million which holds probably only for nearly ideal solid solutions. The concentration dependence of the diffusion activation energy, Q(x) and the frequency factor D(x) follow this rule only up to 30 at% Zn content within the experimental error. Using Tm(x) = [Tsol(x) + Tliq(x)]/2, it is found that In D(x) and Q(x)/Tm(x) have similar concentration dependence.