Advances in the theory of swelling in irradiated metals and alloys

Recent advances in the theory of swelling are reviewed. These include (1) the development of a cascade diffusion theory to treat quantitatively the fluctuations in point defect concentrations caused by locally inhomogeneous point defect production, (2) the incorporation of mobile helium and its effects on void growth into the theory, and (3) the spatial variation in swelling during charged particle bombardment. Summaries of (1) and (2) are given. A more complete development of (3) is presented.