1995 Volume 36 Issue 5 Pages 639-644
The role of interstitials in the radiation-induced segregation (RIS) process in a face-centered cubic (fcc) binary alloy is investigated with a newly developed model. The model considers three types of interstitial dumbbells, their diffusion and conversion via an interstitialcy migration, recombination with a vacancy, and vacancy diffusion through the position exchange with a lattice atom. Analysis of RIS kinetics in the Cu–Au alloy is used to verify the model, and good agreement is obtained with experimental measurements. The relationship is examined between the present model and the Wiedersich-Okamoto-Lam model (WOL model) in which the mixed dumbbell movement is neglected. Effective diffusion coefficients are derived which incorporate the effect of the mixed dumbbell into the WOL model formulation.