Two kinds of films were prepared to study the effect of microstructure on helium migration in Ti tritides. Both films showed different release behaviors and helium bubble distributions. In the film consisting of colum...Two kinds of films were prepared to study the effect of microstructure on helium migration in Ti tritides. Both films showed different release behaviors and helium bubble distributions. In the film consisting of columnar grains, a twolayered structure was observed. Inclusions with a strip feature were found at the grain boundary, and no helium bubbles were distributed in these inclusions. However, helium preferred to migrate to the boundaries of these inclusions. Bubble linkage as a ribbon-like feature developed parallel to the film surface in the film consisting of columnar grains. More cracks were developed at the grain boundaries of the film consisting of columnar grains, although the helium content in the film consisting of columnar grains was less than that in the film consisting of equiaxed grains. A surface region with a small number of bubbles, or ＂depleted zone＂, was observed near the surface. The cracks extending to the film surface were the pathways of the critical helium released from the film. The helium migration was strongly influenced by the grain microstructure.展开更多
文摘Two kinds of films were prepared to study the effect of microstructure on helium migration in Ti tritides. Both films showed different release behaviors and helium bubble distributions. In the film consisting of columnar grains, a twolayered structure was observed. Inclusions with a strip feature were found at the grain boundary, and no helium bubbles were distributed in these inclusions. However, helium preferred to migrate to the boundaries of these inclusions. Bubble linkage as a ribbon-like feature developed parallel to the film surface in the film consisting of columnar grains. More cracks were developed at the grain boundaries of the film consisting of columnar grains, although the helium content in the film consisting of columnar grains was less than that in the film consisting of equiaxed grains. A surface region with a small number of bubbles, or ＂depleted zone＂, was observed near the surface. The cracks extending to the film surface were the pathways of the critical helium released from the film. The helium migration was strongly influenced by the grain microstructure.
