Elastic–plastic FEM analysis on low cycle fatigue behavior for alumina dispersion-strengthened copper/stainless steel joint

Abstract

Since the first wall and divertor components of fusion power plants are subjected to severe stresses caused by thermal expansion and electromagnetic forces, it is important to evaluate the fatigue strength of joints. In this study, elastic–plastic finite element analysis was performed for low cycle fatigue behavior of stainless steel/alumina dispersion-strengthened copper (DS Cu) joint in order to investigate the fatigue life and the fracture behavior of the joint. The results showed that a strain concentration occurred at the interface during low cycle fatigue, but as the strain range increased the strain concentration shifted away from the interface and into the DS Cu. The fatigue life and fracture location were evaluated taking into account of the strain concentration. Predictions of the fatigue life and fracture location were consistent with those measured by the low cycle fatigue test.