It was shown that the activation energy, for the migration of vacancies in thermal equilibrium, was 1.06eV. The same value was also obtained for stage-IV recovery after quenching from high temperatures or after being irradiated with high-energy particles some 350000h before. The activation energy which was obtained for recovery stage III was the migration activation energy for interstitials (0.71eV). Radiation-enhanced 63Ni-diffusion was above the stage-III temperature region determined only by interstitials, and below the stage-III temperature region which was determined only by dynamic crowdions. It was noted that dynamic crowdions in pure materials jumped about 40000 times during their lifetime. In recovery stages I and II, correlated interstitial-vacancy pairs annihilated. The activation energy for the annihilation of these pairs increased with increasing distance between correlated interstitials and vacancies. Correlated crowdion-vacancy pairs, and crowdions, annihilated in stage I; in those materials where crowdions were stable.

On the Recovery Stages in FCC Materials. W.Schüle: Journal of Nuclear Materials, 1996, 233-237B, 969-73