Weldability and mechanical properties of AA5083-H112 aluminum alloy and pure copper dissimilar friction spot extrusion welding-brazing

Abstract The friction spot extrusion welding-brazing (FSEW-B) process was employed to join AA5083-H112 aluminum alloy and pure Cu via the use of a Zn interlayer to improve the mechanical properties of the dissimilar joint. The attained data indicated that not only FSEW-B led to the elimination of the keyhole, which is an intrinsic flaw of the Friction Stir Spot Welding (FSSW) process, but also the results showed that adding Zn interlayer was propitious to make less brittle intermetallic compounds (IMCs) like Al4Cu9 at the Cu/Al interface. More importantly, tensile shear results demonstrated an improvement in the strength and ductility of the FSEW-B weld sample (reached 156.2 MPa), which is attributable to the lack of keyhole defect and brittle IMCs in the joint.