Evaluation of strength on dissimilar metal joints for ITER first wall components

Nishi, Hiroshi; Enoeda, Mikio; Hirose, Takanori; Tsuru, Daigo; Tanigawa, Hisashi

The first wall of ITER blanket includes beryllium armor tiles joined to CuCrZr heat sink and stainless steel. Therefore dissimilar materials joints are indispensable for fabricating the high heat flux components. Since these joints must withstand thermal and mechanical loads caused by the plasma and electromagnetic force, it is important to evaluate the strength and thermal fatigue life of dissimilar materials joints. When the dissimilar materials joints are subjected by external force and thermal loading, the stress of the joint may indicate singularity at the interface edge. Since the stress singularity may lower the strength of joints, the singularity is evaluated numerically for the various materials combinations and joint configuration to be used in high heat flux components of fusion reactors in this investigation. Moreover, tensile test and elasto-plastic FEM analysis are performed to investigate the fracture behavior of the various joints obtained the FW mock-up.