Effect of Laser Beam Oscillation on Laser Welding–Brazing of Ti/Al Dissimilar Metals

Abstract

Ti4Al6V and 6061 Al dissimilar metals were butt welded by the laser oscillating welding method. The effects of laser offset, oscillation frequency, and energy distribution on the formation, microstructure, and tensile properties of dissimilar metal joints are discussed in detail. The experimental results show that the Ti6Al4V was micro melted with a laser offset of 1.1 mm, and a large number of intermetallic compounds (IMCs) were formed on the side of the Ti6Al4V. Additionally, there were some porosity defects in the fusion zone (FZ) due to an inappropriate laser oscillation frequency. When the laser offset was increased to 1.2 mm, the IMC distribution was uniform and the thickness was controlled below 2 μm. The porosity defects in the FZ decreased and the tensile strength of the joints increased significantly. The maximum value of tensile strength reached 173 MPa at a laser frequency of 28 Hz.