Experimental and numerical study on fatigue performance for TIG welding and EB welding of RAFM steel plate

Abstract The Reduced Activation Martensitic/Ferritic steel (RAFM steel) is known as one of the most important materials for future fusion reactor blanket. Welding process is unavoidable during the blanket manufacturing, so it is necessary to research the welding performance of the RAFM steel. Simulations and experiments regarding fatigue behavior of the RAFM steel welding specimens have been done in this paper. The simulation of fatigue behavior of tungsten inert gas (TIG) welding and electron beam (EB) welding of the RAFM steel were carried out by using ANSYS mechanical engineering code. The fatigue behavior for two types RAFM steel specimens of TIG welding and EB welding were also tested by SDS200 electro-hydraulic servo fatigue testing machine. The fatigue performance of the weld joint both for TIG welding and EB welding was tested by applying the same gradient load. The experimental results were studied to analyze the impact of fatigue resistance for the analyzed welding technologies of RAFM steel, and the results indicate that the EB welding is stable under increasing stress. Outcomes of this study can provide some beneficial indications for the blanket design of China Fusion Engineering Testing Reactor (CFETR) in the future.