Joining of CP-Ti/Q345 sheets by Cu-based filler metal and effect on interface

The water cooling system was developed to inhibit cracking at explosively bonding interface. The microstructures of the welded joint were analyzed by means of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). Mechanical properties were evaluated by microhardness, tensile tests and three-point bend tests. The joint free of cracks was obtained with Cu-V-Ag based flux-cored wire. The Cu-V-Ag weld metal exhibited good bonding with adjacent materials. The joint had an average tensile strength of 511 MPa. Almost zero bend ductility was revealed in the welded joint. Fractured surface of the bend specimen was dominated by brittle morphology. It was primary due to the high volume fraction of Ti-Cu intermetallics dispersed in the weld metal.