The diffusion coefficients for Ib metals in the -phase were determined, at temperatures ranging from 980 to 1120K, by extrapolating the concentration dependences of the interdiffusion coefficients to infinite dilution. The results could be described by the relationships:

Ag:     D (m2/s) = 6.5 x 10-6exp[-240(kJ/mol)/RT]

Au:     D (m2/s) = 2.5 x 10-8exp[-188(kJ/mol)/RT]

Cu:     D (m2/s) = 3.8 x 10-5exp[-195(kJ/mol)/RT]

The Cu underwent fast impurity diffusion, while Ag and Au behaved normally. In the case of normal diffusion, a linear relationship was observed between the logarithm of the pre-exponential factor and the activation energy. The plots for fast diffusers were located far above the line for normal diffusers. It was concluded that the fast diffusion could be characterized by a large pre-exponential factor.

O.Taguchi, Y.Iijima: Philosophical Magazine A, 1995, 72[6], 1649-55