Materials considerations in tritium handling systems

The interaction of tritium with materials of construction is a key area of consideration in addressing tritium handling and containment requirements for fusion systems. In this context, dissolution, diffusion, and permeation of hydrogen isotopes are the dominant properties of interest. The factors which nest heavily influence these properties relate to choice of material, surface and bulk microstructure, impurity interactions, and radiolytic effects (in the case of tritium). The interactions of tritium with normetallic materials are not nearly as well understood as those between tritium and metals, and substantial impetus exists for research in this area. The basis for selecting and qualifying materials for tritium service in fusion facilities is reasonably well established, but must be expanded and focused towards the specific needs of the fusion program.