Defect creation induced by helium bubble growth near dislocations in titanium

Abstract

ABSTRACTDefect creation induced by helium bubble growth near dislocations in titanium has been studied using molecular dynamics simulations. When the helium bubble is nucleated on the side of the slip plane with a full atomic layer at 0 K, it grows towards the slip plane and easily crosses it. Defects prefer to form on the side toward which the bubble grows, and drift toward the side of the slip plane that lacks an atomic layer. However, the substrate on the other side of the helium bubble keeps an almost perfect crystal structure. At 300 K, with relaxation of the system, the substrate around the helium bubble can have a nearly perfect crystal structure. The appearance of the perfect crystal structure is based on the movement of the metal atoms to the atom layers that contain the helium bubble. The nearer the atomic layer is to the helium bubble, the earlier the complete lattice structure appears.