Innovative combined arc welding technique for joining Ti–6Al–4V and Inconel 718 dissimilar metals

This paper introduces a combined joining approach that integrates spatially arranged combined twin-wire arc welding with single-wire arc welding based on additive manufacturing technology to join Ti–6Al–4V and Inconel 718. Copper (S214), vanadium (V01), and niobium (Nb01) alloy wires were employed to fabricate a 3 mm thick multi-pass joint consisting of Ti–6Al–4V/V/Cu/Inconel 718 buttering and backing joint and Ti–6Al–4V/Nb/Cu/Inconel 718 filling joint. No intermetallic compounds were detected at the Ti–6Al–4V/Inconel 718 joint, and the phase composition of the V/Cu and Nb/Cu interfaces included V(S,S)+Cu(S,S) and Nb(S,S)+Cu(S,S), (S,S denotes solid solution), respectively. The joint fractured at the Cu weld and had a tensile strength of 390 MPa. This approach provides a novel strategy for dissimilar-metal joining which will expand industrial applications.