Interstitial-vacancy recombination for model bcc transition metals

• Published in: Journal of nuclear materials Vol. 171; no. 2; pp. 412 - 414
• Main Authors: Grant, B., Harder, J.M., Bacon, D.J.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.1990
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/0022-3115(90)90389-5

The survival of vacancies and self-interstitials formed as Frenkel pairs in metals is at the heart of many phenomena associated with radiation damage, for the fraction that avoids recombination determines the scale of changes in material properties. The size and shape of the volume around a vacancy within which an interstitial can spontaneously annihilate its partner are therefore of considerable importance for the successful development of models for describing radiation damage. The nature of this recombination volume determines, in fact, the recombination coefficient that appears in the rate-theory equations of damage processes. The size and shape of the volume for two different self-interstitial forms in the body-centred-cubic (bcc) metal structure, were examined and this was done using atomic-scale computer simulation of spontaneous recombination at 0K. By the use of many-body interatomic potentials developed recently for two of the bcc transition metals, the sensitivity of the parameters of the recombination volume were tested for both the interstitial configuration and the properties of the potential. These results suggest that in a "standard" metal in which the < 110 > dumbbell is stable, anisotropy in the shape of the recombination volume of a metastable crowdion will not be very important, although the size of the volume may be. The shape would be an important factor for a metal in which the crowdion were stable. 6 ref.--AA