Helium production and material damage rate assessment in EU DEMO HCPB divertor

Abstract

EU DEMO should be the first demonstrative fusion power plant, and it is expected to show that net electric energy can be produced and supplied to the grid. The availability and lifetime of the plant will be comparable to that of a commercial fusion power plant. The capacity to provide considerable net electric power safely and continuously to the grid (from 100 MW to 500 MW) is one of DEMO's significant purposes. The neutrons cause defects, leading to the transmutation of elemental atoms when interacting with the divertor component materials. These reactions produce gases, notably helium, which can induce material swelling and embrittlement. In this paper, the DPA and helium production in divertor has been assessed, mainly focusing on the structural material: EUROFER. Helium production rates reach around 117 appm/fpy as the peak, while DPA values reach about 4 dpa/fpy as the maximum value. These calculations were performed using the MCNP6 code with FENDL 3.2 nuclear data and the ADVANTG tool.