Pulsed laser welding of Ti-6Al-4V titanium alloy to AISI 316L stainless steel using Cu/Nb bilayer

Laser welding of TC4 titanium alloy and AISI 316L stainless steel was performed by inserting Cu/Nb bilayer. If high laser power was employed, microstructure of fusion zone of titanium alloy side was mainly composed of (Nb, Ti) solid solution, and Ti-Cu phases would be produced near fusion zone between Cu and Nb. If relatively low laser power was applied, the formation of cracks could be slightly inhibited, and microstructure in fusion zone between Cu and Nb was replaced by (Cu, Nb) solid solution. Owing to the formation of cracks, maximum tensile strength of weld joints was only 114 MPa. (C) 2019 Elsevier B.V. All rights reserved.