Mechanical Properties And Joining Mechanism of Magnetic Pulse Welded Aluminum To Titanium

Magnetic pulse welding of dissimilar aluminum and titanium was investigated to optimize process parameters in terms of discharge voltage, radial gap and overlapping length. Moreover, impacting modes at different overlapping lengths were discussed. The joining mechanism was analyzed from aspects of microstructure, composition and hardness distribution. The shear strength increased with increasing discharge voltages, whereas shear strength decreased at first and then increased with the increasing radial gap, which has a more significant influence on shear strength than discharge voltage. Three impacting modes were proposed as bidirectional impacting, overall impacting and single-orientation impacting. However, the single-orientation impacting mode has the highest effective joining ratio. The welded joints were divided into four transition layer interfaces: continuous transition zone, transition zone with cracks, intermittent transition zone, and non-transition zone. Waves and intermetallic compounds are the two characteristics of the Al-Ti joint welded by magnetic pulse welding. The metal's hardness near the joint surface is higher than that of the base metal. In addition, Al3Ti and aluminum base metal were found in the transition layer of the joint.