Time-resolved X-ray radiography was used to monitor interdiffusion processes in situ in liquid alloys. Temperature- and composition-dependent interdiffusion coefficients (DAlCu) were measured in Al-rich Al-Cu melts. At constant temperature, DAlCu exhibits only a weak dependence upon the alloy composition. As compared to self-diffusion, interdiffusion was enhanced by a factor of about 3. The results demonstrated that it was not possible to express interdiffusion in terms of self-diffusion and thermodynamic driving forces.

Diffusion in Al-Cu Melts Studied by Time-Resolved X-ray Radiography. B.Zhang, A.Griesche, A.Meyer: Physical Review Letters, 2010, 104[3], 035902