Interdiffusion in copper-base Cu-AI solid solutions

Interdiffusion in couples consisting of pure copper and a Cu-12.2 at. pet A1 alloy has been studied in the temperature range between 977 and 1277 K. Concentration of aluminum was determined by EPMA. The interdiffusion coefficient increased with the atomic fraction of aluminum, N_ai, in solid solution: D₀(m²/s) = 0.43 × 10^-4 and Q (kJ/tool) =194000 — 180000 N_a1 The Kirkendall effect has also been studied in the temperature range from 977 to 1277 K. The markers moved toward the aluminum-rich side. The ratio of the tracer-diffusion coefficient of aluminum, D _* ^Al , to that of copper, D _* ^Cu , at the marker position where N_a1 = 0.073, was estimated at 1.7 to 3.7; this ratio showed a tendency to increase with temperature.