Self-interstitials in gold-silver alloys

The enhancement of diffusion by 2 MeV-electron irradiation was : easured as a function of flux and temperature in two gold-silver alloys containing 15.0 and 26.82 at. % Ag. The increase of the degree of order during irradiation was determined in situ by electrical resistivity techniques. The activation energy of the ordering process during irradiation was about 0.32 eV in virgin specimens of both alloys. Beyond an irradiation dose of about 1018 electr./cm2 a nearly temperature independent enhancement of diffusion resulted. For the temperature dependent enhancement of diffusion a square root dependence and for the nearly temperature independent enhanced diffusion a linear dependence of the diffusion rate from and the electron flux was found. From these results the activation migration energy of self-interstitials was derived to be 0.64 eV and it is shown that the ordering rate during irradiation is determined by their migration. With the identification of self-interstitials and of crowdions previously, : he existence of two stable interstitial configurations in gold-silver alloys is evident