Joining of 304SS and pure copper by rapidly solidified Cu-based braze alloy

The joining behavior of 304SS and Cu joint is important for the component materials of the first wall and divertor in the International Thermonuclear Fusion Experiment Reactor (ITER). In this research, the joining of 304 stainless steel (SS) and pure copper is done by rapidly solidified Cu-40Mn-10Ni brazing alloy at 920 °C for 5 min. The SEM-BSE image of joint area shows homogeneous microstructure. The butt joint of 304SS and pure Cu breaks at the tensile strength of 260 MPa and several dimples are observed at the fracture surface. It reveals ductile nature and strong bonding between two dissimilar metals. The X-ray diffraction of fracture surface explains the formation of solid solution phases with a little amount of intermetallics.