Diffusion coefficients were determined, in alloys which contained 16.9 to 17.9at%Sn, at 874 to 993K by using the Boltzmann-Matano method. In the β-phase, the interdiffusion coefficient increased with the Sn content. However, it decreased markedly with increasing Sn content in the γ-phase; except at 874K. In the latter case, the interdiffusion coefficient was concentration-independent. Kirkendall markers moved towards the Cu-rich side, and the concentration at the marker was equal to 14.5at%Sn. At this composition, the coefficient of Cu and Sn diffusion was given by:

D (cm2/s) = 2.58 x 10-1 exp[-103(kJ/mol)/RT]

M.Yokota, M.Nose, H.Mitani: Nippon Kinzoku Gakkaishi, 1980, 44[9], 1007-12