ATOMISTIC COMPUTER-SIMULATION OF THE GROWTH OF HELIUM PLATELETS IN NICKEL

In order to study the nucleation and the two-dimensional growth mode of helium aggregates in nickel, we have performed static computer simulations. The results of these simulations show that a helium-filled aggregate tends to expel neighbouring atoms at its outer edges. These emitted atoms are displaced in the direction of a nearest octahedral position and it is established that they are bound to the cluster. The results indicate that a helium-filled aggregate tends to grow in a planar way and that an interstitial loop is formed by the emitted atoms. The two-dimensional growth occurs parallel with the closed-packed planes.