Research on the performance of laser-MIG arc tandem welding of CP-Ti/304 stainless steel bimetallic sheets

In this study, CP-Ti/304 stainless steel (SS) bimetallic sheets were prepared without the formation of Ti-Fe intermetallics in the joint. This required preparing a groove in the flyer and parent layer, and melting S211 wire using laser-MIG arc welding in tandem. The laser was used for the parent layer metal (CP-Ti) and the MIG arc was used for melting the S211 wire and filling the flyer layer groove. As the melting points of the parent layer metal CP-Ti (1660 °C) and the flyer layer metal 304 SS (1454 °C) were higher than the fill wire S211 (965–1035 °C), the parent and flyer layer metals were joined without melting. Liquid mixing of dissimilar metals was avoided and Ti-Fe intermetallics were not formed. The joint was observed to fracture at the laser weld zone and the right side of MIG arc weld zone, with a maximum tensile strength of approximately 680 MPa.