A study on laser welding of dissimilar joints of Ti6Al4V and AA7075 using a cu interlayer: Mechanical properties and corrosion behaviour

This study investigates the use of a copper (Cu) interlayer in dissimilar laser welding between AA7075 and Ti6Al4V alloys. The primary purpose of the Cu interlayer is to reduce the formation of brittle intermetallic compounds (IMCs), which can weaken the mechanical integrity of the welded joints. Corrosion performance was examined using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests. The findings reveal that incorporating the Cu interlayer significantly enhances the fusion between the dissimilar alloys, resulting in joints with improved mechanical strength (240 MPa) and corrosion resistance. Corrosion tests showed the joint had intermediate corrosion resistance (corrosion current density i(Corr) of 1.0297 x 10(-5) A/cm(2) and polarization resistance R-p of 3.07 K Omega.cm(2)) compared to the base material.