Radiation Damage Limitations in the Design of the Wisconsin Tokamak Fusion Reactor

Abstract

AbstractA detailed analysis of the radiation damage problems to be expected in a specific D-T fueled fusion reactor has been conducted. The system examined is the 5000-MW(th) University of Wisconsin Tokamak reactor (UWMAK), which is constructed of 20% cold-worked Type-316 stainless steel and operated at a maximum temperature of 500°C and a neutron wall loading of 1.25 MW/m2. The major radiation damage problem appears to be the loss in ductility; that is, the uniform elongation of the Type-316 stainless steel in the UWMAK-I first wall may fall to <0.5% after one to two years of operation. Another serious problem will be the void-induced swelling in the steel. Based on current design equations, the swelling in the steel of the first wall will exceed the design limit of 10% in approximately five years of operation. The wall erosion rate due to neutron and charged-particle sputtering, coupled with exfoliation due to blistering, is calculated to be 0.22 mm/yr. Finally, calculations reveal that the radiation da...