The static and dynamic properties of clusters of up to 30 self-interstitial atoms were studied by using a many-body Finnis-Sinclair type interatomic potential for Zr. The results revealed a qualitative similarity of some properties of clusters to those for cubic metals. In particular, all clusters which were larger than 4 self-interstitial atoms exhibited rapid thermally activated 1-dimensional glide. Due to the structure of the hexagonal close-packed lattice, this mechanism led to 2-dimensional mass transport on basal planes. Some clusters exhibited a behavior which was peculiar to the hexagonal close-packed structure, in that they could migrate 2-dimensionally on the basal plane.

Mobility of Interstitial Clusters in Alpha-Zirconium. N.De Diego, Y.N.Osetsky, D.J.Bacon: Metallurgical and Materials Transactions A, 2002, 32[3A], 783-9